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  • C#: System.Lazy&lt;T&gt; and the Singleton Design Pattern

    - by James Michael Hare
    So we've all coded a Singleton at one time or another.  It's a really simple pattern and can be a slightly more elegant alternative to global variables.  Make no mistake, Singletons can be abused and are often over-used -- but occasionally you find a Singleton is the most elegant solution. For those of you not familiar with a Singleton, the basic Design Pattern is that a Singleton class is one where there is only ever one instance of the class created.  This means that constructors must be private to avoid users creating their own instances, and a static property (or method in languages without properties) is defined that returns a single static instance. 1: public class Singleton 2: { 3: // the single instance is defined in a static field 4: private static readonly Singleton _instance = new Singleton(); 5:  6: // constructor private so users can't instantiate on their own 7: private Singleton() 8: { 9: } 10:  11: // read-only property that returns the static field 12: public static Singleton Instance 13: { 14: get 15: { 16: return _instance; 17: } 18: } 19: } This is the most basic singleton, notice the key features: Static readonly field that contains the one and only instance. Constructor is private so it can only be called by the class itself. Static property that returns the single instance. Looks like it satisfies, right?  There's just one (potential) problem.  C# gives you no guarantee of when the static field _instance will be created.  This is because the C# standard simply states that classes (which are marked in the IL as BeforeFieldInit) can have their static fields initialized any time before the field is accessed.  This means that they may be initialized on first use, they may be initialized at some other time before, you can't be sure when. So what if you want to guarantee your instance is truly lazy.  That is, that it is only created on first call to Instance?  Well, there's a few ways to do this.  First we'll show the old ways, and then talk about how .Net 4.0's new System.Lazy<T> type can help make the lazy-Singleton cleaner. Obviously, we could take on the lazy construction ourselves, but being that our Singleton may be accessed by many different threads, we'd need to lock it down. 1: public class LazySingleton1 2: { 3: // lock for thread-safety laziness 4: private static readonly object _mutex = new object(); 5:  6: // static field to hold single instance 7: private static LazySingleton1 _instance = null; 8:  9: // property that does some locking and then creates on first call 10: public static LazySingleton1 Instance 11: { 12: get 13: { 14: if (_instance == null) 15: { 16: lock (_mutex) 17: { 18: if (_instance == null) 19: { 20: _instance = new LazySingleton1(); 21: } 22: } 23: } 24:  25: return _instance; 26: } 27: } 28:  29: private LazySingleton1() 30: { 31: } 32: } This is a standard double-check algorithm so that you don't lock if the instance has already been created.  However, because it's possible two threads can go through the first if at the same time the first time back in, you need to check again after the lock is acquired to avoid creating two instances. Pretty straightforward, but ugly as all heck.  Well, you could also take advantage of the C# standard's BeforeFieldInit and define your class with a static constructor.  It need not have a body, just the presence of the static constructor will remove the BeforeFieldInit attribute on the class and guarantee that no fields are initialized until the first static field, property, or method is called.   1: public class LazySingleton2 2: { 3: // because of the static constructor, this won't get created until first use 4: private static readonly LazySingleton2 _instance = new LazySingleton2(); 5:  6: // Returns the singleton instance using lazy-instantiation 7: public static LazySingleton2 Instance 8: { 9: get { return _instance; } 10: } 11:  12: // private to prevent direct instantiation 13: private LazySingleton2() 14: { 15: } 16:  17: // removes BeforeFieldInit on class so static fields not 18: // initialized before they are used 19: static LazySingleton2() 20: { 21: } 22: } Now, while this works perfectly, I hate it.  Why?  Because it's relying on a non-obvious trick of the IL to guarantee laziness.  Just looking at this code, you'd have no idea that it's doing what it's doing.  Worse yet, you may decide that the empty static constructor serves no purpose and delete it (which removes your lazy guarantee).  Worse-worse yet, they may alter the rules around BeforeFieldInit in the future which could change this. So, what do I propose instead?  .Net 4.0 adds the System.Lazy type which guarantees thread-safe lazy-construction.  Using System.Lazy<T>, we get: 1: public class LazySingleton3 2: { 3: // static holder for instance, need to use lambda to construct since constructor private 4: private static readonly Lazy<LazySingleton3> _instance 5: = new Lazy<LazySingleton3>(() => new LazySingleton3()); 6:  7: // private to prevent direct instantiation. 8: private LazySingleton3() 9: { 10: } 11:  12: // accessor for instance 13: public static LazySingleton3 Instance 14: { 15: get 16: { 17: return _instance.Value; 18: } 19: } 20: } Note, you need your lambda to call the private constructor as Lazy's default constructor can only call public constructors of the type passed in (which we can't have by definition of a Singleton).  But, because the lambda is defined inside our type, it has access to the private members so it's perfect. Note how the Lazy<T> makes it obvious what you're doing (lazy construction), instead of relying on an IL generation side-effect.  This way, it's more maintainable.  Lazy<T> has many other uses as well, obviously, but I really love how elegant and readable it makes the lazy Singleton.

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  • C# 4.0: Dynamic Programming

    - by Paulo Morgado
    The major feature of C# 4.0 is dynamic programming. Not just dynamic typing, but dynamic in broader sense, which means talking to anything that is not statically typed to be a .NET object. Dynamic Language Runtime The Dynamic Language Runtime (DLR) is piece of technology that unifies dynamic programming on the .NET platform, the same way the Common Language Runtime (CLR) has been a common platform for statically typed languages. The CLR always had dynamic capabilities. You could always use reflection, but its main goal was never to be a dynamic programming environment and there were some features missing. The DLR is built on top of the CLR and adds those missing features to the .NET platform. The Dynamic Language Runtime is the core infrastructure that consists of: Expression Trees The same expression trees used in LINQ, now improved to support statements. Dynamic Dispatch Dispatches invocations to the appropriate binder. Call Site Caching For improved efficiency. Dynamic languages and languages with dynamic capabilities are built on top of the DLR. IronPython and IronRuby were already built on top of the DLR, and now, the support for using the DLR is being added to C# and Visual Basic. Other languages built on top of the CLR are expected to also use the DLR in the future. Underneath the DLR there are binders that talk to a variety of different technologies: .NET Binder Allows to talk to .NET objects. JavaScript Binder Allows to talk to JavaScript in SilverLight. IronPython Binder Allows to talk to IronPython. IronRuby Binder Allows to talk to IronRuby. COM Binder Allows to talk to COM. Whit all these binders it is possible to have a single programming experience to talk to all these environments that are not statically typed .NET objects. The dynamic Static Type Let’s take this traditional statically typed code: Calculator calculator = GetCalculator(); int sum = calculator.Sum(10, 20); Because the variable that receives the return value of the GetCalulator method is statically typed to be of type Calculator and, because the Calculator type has an Add method that receives two integers and returns an integer, it is possible to call that Sum method and assign its return value to a variable statically typed as integer. Now lets suppose the calculator was not a statically typed .NET class, but, instead, a COM object or some .NET code we don’t know he type of. All of the sudden it gets very painful to call the Add method: object calculator = GetCalculator(); Type calculatorType = calculator.GetType(); object res = calculatorType.InvokeMember("Add", BindingFlags.InvokeMethod, null, calculator, new object[] { 10, 20 }); int sum = Convert.ToInt32(res); And what if the calculator was a JavaScript object? ScriptObject calculator = GetCalculator(); object res = calculator.Invoke("Add", 10, 20); int sum = Convert.ToInt32(res); For each dynamic domain we have a different programming experience and that makes it very hard to unify the code. With C# 4.0 it becomes possible to write code this way: dynamic calculator = GetCalculator(); int sum = calculator.Add(10, 20); You simply declare a variable who’s static type is dynamic. dynamic is a pseudo-keyword (like var) that indicates to the compiler that operations on the calculator object will be done dynamically. The way you should look at dynamic is that it’s just like object (System.Object) with dynamic semantics associated. Anything can be assigned to a dynamic. dynamic x = 1; dynamic y = "Hello"; dynamic z = new List<int> { 1, 2, 3 }; At run-time, all object will have a type. In the above example x is of type System.Int32. When one or more operands in an operation are typed dynamic, member selection is deferred to run-time instead of compile-time. Then the run-time type is substituted in all variables and normal overload resolution is done, just like it would happen at compile-time. The result of any dynamic operation is always dynamic and, when a dynamic object is assigned to something else, a dynamic conversion will occur. Code Resolution Method double x = 1.75; double y = Math.Abs(x); compile-time double Abs(double x) dynamic x = 1.75; dynamic y = Math.Abs(x); run-time double Abs(double x) dynamic x = 2; dynamic y = Math.Abs(x); run-time int Abs(int x) The above code will always be strongly typed. The difference is that, in the first case the method resolution is done at compile-time, and the others it’s done ate run-time. IDynamicMetaObjectObject The DLR is pre-wired to know .NET objects, COM objects and so forth but any dynamic language can implement their own objects or you can implement your own objects in C# through the implementation of the IDynamicMetaObjectProvider interface. When an object implements IDynamicMetaObjectProvider, it can participate in the resolution of how method calls and property access is done. The .NET Framework already provides two implementations of IDynamicMetaObjectProvider: DynamicObject : IDynamicMetaObjectProvider The DynamicObject class enables you to define which operations can be performed on dynamic objects and how to perform those operations. For example, you can define what happens when you try to get or set an object property, call a method, or perform standard mathematical operations such as addition and multiplication. ExpandoObject : IDynamicMetaObjectProvider The ExpandoObject class enables you to add and delete members of its instances at run time and also to set and get values of these members. This class supports dynamic binding, which enables you to use standard syntax like sampleObject.sampleMember, instead of more complex syntax like sampleObject.GetAttribute("sampleMember").

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  • MySQL 5.5 brings in new ways to authenticate users

    - by Georgi Kodinov
    Ever wanted to use your server's OS for authenticating MySQL users ? Or the corporate LDAP repository ? Unfortunately options like the above are plentiful nowadays. And providing hard-coded support for protocol X or service Y is not the best possible idea. MySQL 5.5 has taken the step into the right direction by providing an infrastructure allowing one to make the server understand different authentication protocols by creating a set of simple plugins (one for the client and one for the server). So now you can easily extend MySQL to search for and authenticate users in your favorite user directory. In fact the API supplied is so versatile that we took the possibility to re-design the current "native" authentication mechanism into a built-in always-on plugin ! OK, let me give you an example: Imagine we have a bunch of users defined in your OS, e.g. we have a user joro with his respective password. And we have a MySQL instance running on the same computer. It would not be unexpected to need to let joro access and/or modify MySQL data. The first step is to define him as a MySQL user. And there's a problem right there : MySQL's CREATE USER joro@localhost IDENTIFIED BY 'joros_password' statement needs a password. And this is a password in no way related to the password that joro have set up in the OS. What's worse : if joro changes his OS password this will in no way be reflected in MySQL. So he'll need to change his MySQL password in a separate step. Not very convenient, specially when you have a lot of users. This is a laborious setup for joro's DBA as well : he'll have to disable his access in both MySQL and the OS should he decides that joro's out of the "nice" list. Now mysql 5.5 to the rescue: Imagine that the smart DBA has created a MySQL server plugin that will check if the name of the user logging in is a valid and enabled OS name and if the password supplied to the mysql client matches the OS and has called this plugin 'auth_os'. Now all that's left to do is to define joro as a MySQL user that will be authenticated externally. This is done by the following command : CREATE USER 'joro'@'localhost' IDENTIFIED WITH 'auth_os'; Now joro can login to MySQL using his current OS password. Note : joro is still a valid MySQL user, so you can grant privileges to him just like you would for all other users. What's better: you can have users that authenticate using different mechanisms in the same server. So you can e.g. safely experiment with external authentication for selected users while keeping your current user base operational. What happens under the hood when joro logs in ? The server will find out by the user definition that it needs to use a non-default authentication and will ask the client to "switch" to using the appropriate client-side plugin (if of course the client is not already using it). If the client can't do this (e.g. because it's an old client or doesn't have the necessary plugin available) the server will reject the login. Otherwise the server will let the server-side plugin decide (while possibly talking to the client side plugin and the OS user directory) if this is a valid login or not. If it is the login process will continue as usual, while if it's not the login will get rejected. There's a lot more that MySQL 5.5 can do for you than just the simple case above. Stay tuned for more advanced use cases like mapping groups of external users to a single MySQL user (so you won't have to have 1-to-1 mapping between your external user directory and your mysql user repository) or ways to control the process as a DBA. Or you can simply skip ahead and read the relevant topics from MySQL's excellent online documentation. Or take a look at the example plugins in plugin/auth. Or take a look at the test suite in mysql-test/t/plugin_auth.test. Changelog entry: http://dev.mysql.com/doc/refman/5.5/en/news-5-5-7.html Primary new sections: Pluggable authentication Proxy users Client plugin C API functions Revised sections: New PROXY privilege New proxies_priv grant table Passwords might be external New external_user and proxy_user system variables New --default-auth and --plugin-dir mysql options New MYSQL_DEFAULT_AUTH and MYSQL_PLUGIN_DIR options for mysql_options() CREATE USER has IDENTIFIED WITH clause to specify auth plugin GRANT has PROXY privilege, IDENTIFIED WITH clause to specify auth plugin The data structure for writing client plugins

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  • mysql not starting

    - by Eiriks
    I have a server running on rackspace.com, it been running for about a year (collecting data for a project) and no problems. Now it seems mysql froze (could not connect either through ssh command line, remote app (sequel pro) or web (pages using the db just froze). I got a bit eager to fix this quick and rebooted the virtual server, running ubuntu 10.10. It is a small virtual LAMP server (10gig storage - I'm only using 1, 256mb ram -has not been a problem). Now after the reboot, I cannot get mysql to start again. service mysql status mysql stop/waiting I believe this just means mysql is not running. How do I get this running again? service mysql start start: Job failed to start No. Just typing 'mysql' gives: mysql ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (111) There is a .sock file in this folder, 'ls -l' gives: srwxrwxrwx 1 mysql mysql 0 2012-12-01 17:20 mysqld.sock From googleing this for a while now, I see that many talk about the logfile and my.cnf. Logs Not sure witch ones I should look at. This log-file is empty: 'var/log/mysql/error.log', so is the 'var/log/mysql.err' and 'var/log/mysql.log'. my.cnf is located in '/etc/mysql' and looks like this. Can't see anything clearly wrong with it either. # # The MySQL database server configuration file. # # You can copy this to one of: # - "/etc/mysql/my.cnf" to set global options, # - "~/.my.cnf" to set user-specific options. # # One can use all long options that the program supports. # Run program with --help to get a list of available options and with # --print-defaults to see which it would actually understand and use. # # For explanations see # http://dev.mysql.com/doc/mysql/en/server-system-variables.html # This will be passed to all mysql clients # It has been reported that passwords should be enclosed with ticks/quotes # escpecially if they contain "#" chars... # Remember to edit /etc/mysql/debian.cnf when changing the socket location. [client] port = 3306 socket = /var/run/mysqld/mysqld.sock # Here is entries for some specific programs # The following values assume you have at least 32M ram # This was formally known as [safe_mysqld]. Both versions are currently parsed. [mysqld_safe] socket = /var/run/mysqld/mysqld.sock nice = 0 [mysqld] # # * Basic Settings # # # * IMPORTANT # If you make changes to these settings and your system uses apparmor, you may # also need to also adjust /etc/apparmor.d/usr.sbin.mysqld. # user = mysql socket = /var/run/mysqld/mysqld.sock port = 3306 basedir = /usr datadir = /var/lib/mysql tmpdir = /tmp skip-external-locking # # Instead of skip-networking the default is now to listen only on # localhost which is more compatible and is not less secure. bind-address = 127.0.0.1 # # * Fine Tuning # key_buffer = 16M max_allowed_packet = 16M thread_stack = 192K thread_cache_size = 8 # This replaces the startup script and checks MyISAM tables if needed # the first time they are touched myisam-recover = BACKUP #max_connections = 100 #table_cache = 64 #thread_concurrency = 10 # # * Query Cache Configuration # query_cache_limit = 1M query_cache_size = 16M # # * Logging and Replication # # Both location gets rotated by the cronjob. # Be aware that this log type is a performance killer. # As of 5.1 you can enable the log at runtime! #general_log_file = /var/log/mysql/mysql.log #general_log = 1 log_error = /var/log/mysql/error.log # Here you can see queries with especially long duration #log_slow_queries = /var/log/mysql/mysql-slow.log #long_query_time = 2 #log-queries-not-using-indexes # # The following can be used as easy to replay backup logs or for replication. # note: if you are setting up a replication slave, see README.Debian about # other settings you may need to change. #server-id = 1 #log_bin = /var/log/mysql/mysql-bin.log expire_logs_days = 10 max_binlog_size = 100M #binlog_do_db = include_database_name #binlog_ignore_db = include_database_name # # * InnoDB # # InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/. # Read the manual for more InnoDB related options. There are many! # # * Security Features # # Read the manual, too, if you want chroot! # chroot = /var/lib/mysql/ # # For generating SSL certificates I recommend the OpenSSL GUI "tinyca". # # ssl-ca=/etc/mysql/cacert.pem # ssl-cert=/etc/mysql/server-cert.pem # ssl-key=/etc/mysql/server-key.pem [mysqldump] quick quote-names max_allowed_packet = 16M [mysql] #no-auto-rehash # faster start of mysql but no tab completition [isamchk] key_buffer = 16M # # * IMPORTANT: Additional settings that can override those from this file! # The files must end with '.cnf', otherwise they'll be ignored. # !includedir /etc/mysql/conf.d/ I need the data in the database (so i'd like to avoid reinstalling), and I need it back up running again. All hint, tips and solutions are welcomed and appreciated.

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  • Java ME SDK 3.2 is now live

    - by SungmoonCho
    Hi everyone, It has been a while since we released the last version. We have been very busy integrating new features and making lots of usability improvements into this new version. Datasheet is available here. Please visit Java ME SDK 3.2 download page to get the latest and best version yet! Some of the new features in this version are described below. Embedded Application SupportOracle Java ME SDK 3.2 now supports the new Oracle® Java ME Embedded. This includes support for JSR 228, the Information Module Profile-Next Generation API (IMP-NG). You can test and debug applications either on the built-in device emulators or on your device. Memory MonitorThe Memory Monitor shows memory use as an application runs. It displays a dynamic detailed listing of the memory usage per object in table form, and a graphical representation of the memory use over time. Eclipse IDE supportOracle Java ME SDK 3.2 now officially supports Eclipse IDE. Once you install the Java ME SDK plugins on Eclipse, you can start developing, debugging, and profiling your mobile or embedded application. Skin CreatorWith the Custom Device Skin Creator, you can create your own skins. The appearance of the custom skins is generic, but the functionality can be tailored to your own specifications.  Here are the release highlights. Implementation and support for the new Oracle® Java Wireless Client 3.2 runtime and the Oracle® Java ME Embedded runtime. The AMS in the CLDC emulators has a new look and new functionality (Install Application, Manage Certificate Authorities and Output Console). Support for JSR 228, the Information Module Profile-Next Generation API (IMP-NG). The IMP-NG platform is implemented as a subset of CLDC. Support includes: A new emulator for headless devices. Javadocs for the following Oracle APIs: Device Access API, Logging API, AMS API, and AccessPoint API. New demos for IMP-NG features can be run on the emulator or on a real device running the Oracle® Java ME Embedded runtime. New Custom Device Skin Creator. This tool provides a way to create and manage custom emulator skins. The skin appearance is generic, but the functionality, such as the JSRs supported or the device properties, are up to you. This utility only supported in NetBeans. Eclipse plugin for CLDC/MIDP. For the first time Oracle Java ME SDK is available as an Eclipse plugin. The Eclipse version does not support CDC, the Memory Monitor, and the Custom Device Skin Creator in this release. All Java ME tools are implemented as NetBeans plugins. As of the plugin integrates Java ME utilities into the standard NetBeans menus. Tools > Java ME menu is the place to launch Java ME utilities, including the new Skin Creator. Profile > Java ME is the place to work with the Network Monitor and the Memory Monitor. Use the standard NetBeans tools for debugging. Profiling, Network monitoring, and Memory monitoring are integrated with the NetBeans profiling tools. New network monitoring protocols are supported in this release: WMA, SIP, Bluetooth and OBEX, SATSA APDU and JCRMI, and server sockets. Java ME SDK Update Center. Oracle Java ME SDK can be updated or extended by new components. The Update Center can download, install, and uninstall plugins specific to the Java ME SDK. A plugin consists of runtime components and skins. Bug fixes and enhancements. This version comes with a few known problems. All of them have workarounds, so I hope you don't get stuck in these issues when you are using the product. It you cannot watch static variables during an Eclipse debugging session, and sometimes the Variable view cannot show data. In the source code, move the mouse over the required variable to inspect the variable value. A real device shown in the Device Selector is deleted from the Device Manager, yet it still appears. Kill the device manager in the system tray, and relaunch it. Then you will see the device removed from the list. On-device profiling does not work on a device. CPU profiling, networking monitoring, and memory monitoring do not work on the device, since the device runtime does not yet support it. Please do the profiling with your emulator first, and then test your application on the device. In the Device Selector, using Clean Database on real external device causes a null pointer exception. External devices do not have a database recognized by the SDK, so you can disregard this exception message. Suspending the Emulator during a Memory Monitor session hangs the emulator. Do not use the Suspend option (F5) while the Memory Monitor is running. If the emulator is hung, open the Windows task manager and stop the emulator process (javaw). To switch to another application while the Memory Monitor is running, choose Application > AMS Home (F4), and select a different application. Please let us know how we can improve it even better, by sending us your feedback. -Java ME SDK Team

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  • Updating the managed debugging API for .NET v4

    - by Brian Donahue
    In any successful investigation, the right tools play a big part in collecting evidence about the state of the "crime scene" as it was before the detectives arrived. Unfortunately for the Crash Scene Investigator, we don't have the budget to fly out to the customer's site, chalk the outline, and eat their doughnuts. We have to rely on the end-user to collect the evidence for us, which means giving them the fingerprint dust and the evidence baggies and leaving them to it. With that in mind, the Red Gate support team have been writing tools that can collect vital clues with a minimum of fuss. Years ago we would have asked for a memory dump, where we used to get the customer to run CDB.exe and produce dumps that we could analyze in-house, but those dumps were pretty unwieldy (500MB files) and the debugger often didn't dump exactly where we wanted, or made five or more dumps. What we wanted was just the minimum state information from the program at the time of failure, so we produced a managed debugger that captured every first and second-chance exception and logged the stack and a minimal amount of variables from the memory of the application, which could all be exported as XML. This caused less inconvenience to the end-user because it is much easier to send a 65KB XML file in an email than a 500MB file containing all of the application's memory. We don't need to have the entire victim shipped out to us when we just want to know what was under the fingernails. The thing that made creating a managed debugging tool possible was the MDbg Engine example written by Microsoft as part of the Debugging Tools for Windows distribution. Since the ICorDebug interface is a bit difficult to understand, they had kindly created some wrappers that provided an event-driven debugging model that was perfect for our needs, but .NET 4 applications under debugging started complaining that "The debugger's protocol is incompatible with the debuggee". The introduction of .NET Framework v4 had changed the managed debugging API significantly, however, without an update for the MDbg Engine code! After a few hours of research, I had finally worked out that most of the version 4 ICorDebug interface still works much the same way in "legacy" v2 mode and there was a relatively easy fix for the problem in that you can still get a reference to legacy ICorDebug by changing the way the interface is created. In .NET v2, the interface was acquired using the CreateDebuggingInterfaceFromVersion method in mscoree.dll. In v4, you must first create IClrMetaHost, enumerate the runtimes, get an ICLRRuntimeInfo interface to the .NET 4 runtime from that, and use the GetInterface method in mscoree.dll to return a "legacy" ICorDebug interface. The rest of the MDbg Engine will continue working the old way. Here is how I had changed the MDbg Engine code to support .NET v4: private void InitFromVersion(string debuggerVersion){if( debuggerVersion.StartsWith("v1") ){throw new ArgumentException( "Can't debug a version 1 CLR process (\"" + debuggerVersion + "\"). Run application in a version 2 CLR, or use a version 1 debugger instead." );} ICorDebug rawDebuggingAPI=null;if (debuggerVersion.StartsWith("v4")){Guid CLSID_MetaHost = new Guid("9280188D-0E8E-4867-B30C-7FA83884E8DE"); Guid IID_MetaHost = new Guid("D332DB9E-B9B3-4125-8207-A14884F53216"); ICLRMetaHost metahost = (ICLRMetaHost)NativeMethods.ClrCreateInterface(CLSID_MetaHost, IID_MetaHost); IEnumUnknown runtimes = metahost.EnumerateInstalledRuntimes(); ICLRRuntimeInfo runtime = GetRuntime(runtimes, debuggerVersion); //Defined in metahost.hGuid CLSID_CLRDebuggingLegacy = new Guid(0xDF8395B5, 0xA4BA, 0x450b, 0xA7, 0x7C, 0xA9, 0xA4, 0x77, 0x62, 0xC5, 0x20);Guid IID_ICorDebug = new Guid("3D6F5F61-7538-11D3-8D5B-00104B35E7EF"); Object res;runtime.GetInterface(ref CLSID_CLRDebuggingLegacy, ref IID_ICorDebug, out res); rawDebuggingAPI = (ICorDebug)res; }elserawDebuggingAPI = NativeMethods.CreateDebuggingInterfaceFromVersion((int)CorDebuggerVersion.Whidbey,debuggerVersion);if (rawDebuggingAPI != null)InitFromICorDebug(rawDebuggingAPI);elsethrow new ArgumentException("Support for debugging version " + debuggerVersion + " is not yet implemented");} The changes above will ensure that the debugger can support .NET Framework v2 and v4 applications with the same codebase, but we do compile two different applications: one targeting v2 and the other v4. As a footnote I need to add that some missing native methods and wrappers, along with the EnumerateRuntimes method code, came from the Mindbg project on Codeplex. Another change is that when using the MDbgEngine.CreateProcess to launch a process in the debugger, do not supply a null as the final argument. This does not work any more because GetCORVersion always returns "v2.0.50727" as the function has been deprecated in .NET v4. What's worse is that on a system with only .NET 4, the user will be prompted to download and install .NET v2! Not nice! This works much better: proc = m_Debugger.CreateProcess(ProcessName, ProcessArgs, DebugModeFlag.Default,String.Format("v{0}.{1}.{2}",System.Environment.Version.Major,System.Environment.Version.Minor,System.Environment.Version.Build)); Microsoft "unofficially" plan on updating the MDbg samples soon, but if you have an MDbg-based application, you can get it working right now by changing one method a bit and adding a few new interfaces (ICLRMetaHost, IEnumUnknown, and ICLRRuntimeInfo). The new, non-legacy implementation of MDbg Engine will add new, interesting features like dump-file support and by association I assume garbage-collection/managed object stats, so it will be well worth looking into if you want to extend the functionality of a managed debugger going forward.

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  • C# 4.0: Named And Optional Arguments

    - by Paulo Morgado
    As part of the co-evolution effort of C# and Visual Basic, C# 4.0 introduces Named and Optional Arguments. First of all, let’s clarify what are arguments and parameters: Method definition parameters are the input variables of the method. Method call arguments are the values provided to the method parameters. In fact, the C# Language Specification states the following on §7.5: The argument list (§7.5.1) of a function member invocation provides actual values or variable references for the parameters of the function member. Given the above definitions, we can state that: Parameters have always been named and still are. Parameters have never been optional and still aren’t. Named Arguments Until now, the way the C# compiler matched method call definition arguments with method parameters was by position. The first argument provides the value for the first parameter, the second argument provides the value for the second parameter, and so on and so on, regardless of the name of the parameters. If a parameter was missing a corresponding argument to provide its value, the compiler would emit a compilation error. For this call: Greeting("Mr.", "Morgado", 42); this method: public void Greeting(string title, string name, int age) will receive as parameters: title: “Mr.” name: “Morgado” age: 42 What this new feature allows is to use the names of the parameters to identify the corresponding arguments in the form: name:value Not all arguments in the argument list must be named. However, all named arguments must be at the end of the argument list. The matching between arguments (and the evaluation of its value) and parameters will be done first by name for the named arguments and than by position for the unnamed arguments. This means that, for this method definition: public static void Method(int first, int second, int third) this call declaration: int i = 0; Method(i, third: i++, second: ++i); will have this code generated by the compiler: int i = 0; int CS$0$0000 = i++; int CS$0$0001 = ++i; Method(i, CS$0$0001, CS$0$0000); which will give the method the following parameter values: first: 2 second: 2 third: 0 Notice the variable names. Although invalid being invalid C# identifiers, they are valid .NET identifiers and thus avoiding collision between user written and compiler generated code. Besides allowing to re-order of the argument list, this feature is very useful for auto-documenting the code, for example, when the argument list is very long or not clear, from the call site, what the arguments are. Optional Arguments Parameters can now have default values: public static void Method(int first, int second = 2, int third = 3) Parameters with default values must be the last in the parameter list and its value is used as the value of the parameter if the corresponding argument is missing from the method call declaration. For this call declaration: int i = 0; Method(i, third: ++i); will have this code generated by the compiler: int i = 0; int CS$0$0000 = ++i; Method(i, 2, CS$0$0000); which will give the method the following parameter values: first: 1 second: 2 third: 1 Because, when method parameters have default values, arguments can be omitted from the call declaration, this might seem like method overloading or a good replacement for it, but it isn’t. Although methods like this: public static StreamReader OpenTextFile( string path, Encoding encoding = null, bool detectEncoding = true, int bufferSize = 1024) allow to have its calls written like this: OpenTextFile("foo.txt", Encoding.UTF8); OpenTextFile("foo.txt", Encoding.UTF8, bufferSize: 4096); OpenTextFile( bufferSize: 4096, path: "foo.txt", detectEncoding: false); The complier handles default values like constant fields taking the value and useing it instead of a reference to the value. So, like with constant fields, methods with parameters with default values are exposed publicly (and remember that internal members might be publicly accessible – InternalsVisibleToAttribute). If such methods are publicly accessible and used by another assembly, those values will be hard coded in the calling code and, if the called assembly has its default values changed, they won’t be assumed by already compiled code. At the first glance, I though that using optional arguments for “bad” written code was great, but the ability to write code like that was just pure evil. But than I realized that, since I use private constant fields, it’s OK to use default parameter values on privately accessed methods.

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  • Your thoughts on Best Practices for Scientific Computing?

    - by John Smith
    A recent paper by Wilson et al (2014) pointed out 24 Best Practices for scientific programming. It's worth to have a look. I would like to hear opinions about these points from experienced programmers in scientific data analysis. Do you think these advices are helpful and practical? Or are they good only in an ideal world? Wilson G, Aruliah DA, Brown CT, Chue Hong NP, Davis M, Guy RT, Haddock SHD, Huff KD, Mitchell IM, Plumbley MD, Waugh B, White EP, Wilson P (2014) Best Practices for Scientific Computing. PLoS Biol 12:e1001745. http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001745 Box 1. Summary of Best Practices Write programs for people, not computers. (a) A program should not require its readers to hold more than a handful of facts in memory at once. (b) Make names consistent, distinctive, and meaningful. (c) Make code style and formatting consistent. Let the computer do the work. (a) Make the computer repeat tasks. (b) Save recent commands in a file for re-use. (c) Use a build tool to automate workflows. Make incremental changes. (a) Work in small steps with frequent feedback and course correction. (b) Use a version control system. (c) Put everything that has been created manually in version control. Don’t repeat yourself (or others). (a) Every piece of data must have a single authoritative representation in the system. (b) Modularize code rather than copying and pasting. (c) Re-use code instead of rewriting it. Plan for mistakes. (a) Add assertions to programs to check their operation. (b) Use an off-the-shelf unit testing library. (c) Turn bugs into test cases. (d) Use a symbolic debugger. Optimize software only after it works correctly. (a) Use a profiler to identify bottlenecks. (b) Write code in the highest-level language possible. Document design and purpose, not mechanics. (a) Document interfaces and reasons, not implementations. (b) Refactor code in preference to explaining how it works. (c) Embed the documentation for a piece of software in that software. Collaborate. (a) Use pre-merge code reviews. (b) Use pair programming when bringing someone new up to speed and when tackling particularly tricky problems. (c) Use an issue tracking tool. I'm relatively new to serious programming for scientific data analysis. When I tried to write code for pilot analyses of some of my data last year, I encountered tremendous amount of bugs both in my code and data. Bugs and errors had been around me all the time, but this time it was somewhat overwhelming. I managed to crunch the numbers at last, but I thought I couldn't put up with this mess any longer. Some actions must be taken. Without a sophisticated guide like the article above, I started to adopt "defensive style" of programming since then. A book titled "The Art of Readable Code" helped me a lot. I deployed meticulous input validations or assertions for every function, renamed a lot of variables and functions for better readability, and extracted many subroutines as reusable functions. Recently, I introduced Git and SourceTree for version control. At the moment, because my co-workers are much more reluctant about these issues, the collaboration practices (8a,b,c) have not been introduced. Actually, as the authors admitted, because all of these practices take some amount of time and effort to introduce, it may be generally hard to persuade your reluctant collaborators to comply them. I think I'm asking your opinions because I still suffer from many bugs despite all my effort on many of these practices. Bug fix may be, or should be, faster than before, but I couldn't really measure the improvement. Moreover, much of my time has been invested on defence, meaning that I haven't actually done much data analysis (offence) these days. Where is the point I should stop at in terms of productivity? I've already deployed: 1a,b,c, 2a, 3a,b,c, 4b,c, 5a,d, 6a,b, 7a,7b I'm about to have a go at: 5b,c Not yet: 2b,c, 4a, 7c, 8a,b,c (I could not really see the advantage of using GNU make (2c) for my purpose. Could anyone tell me how it helps my work with MATLAB?)

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  • CodePlex Daily Summary for Thursday, March 11, 2010

    CodePlex Daily Summary for Thursday, March 11, 2010New ProjectsASP.NET Wiki Control: This ASP.NET user control allows you to embed a very useful wiki directly into your already existing ASP.NET website taking advantage of the popula...BabyLog: Log baby daily activity.buddyHome: buddyHome is a project that can make your home smarter. as good as your buddy. Cloud Community: Cloud Community makes it easier for organizations to have a simple to use community platform. Our mission is to create an easy to use community pl...Community Connectors for Microsoft CRM 4.0: Community Connectors for Microsoft CRM 4.0 allows Microsoft CRM 4.0 customers and partners to monitor and analyze customers’ interaction from their...Console Highlighter: Hightlights Microsoft Windows Command prompt (cmd.exe) by outputting ANSI VT100 Control sequences to color the output. These sequences are not hand...Cornell Store: This is IN NO WAY officially affiliated or related to the Cornell University store. Instead, this is a project that I am doing for a class. Ther...DevUtilities: This project is for creating some utility tools, and they will be useful during the development.DotNetNuke® Skin Maple: A DotNetNuke Design Challenge skin package submitted to the "Personal" category by DyNNamite.co.uk. The package includes 4 color variations and sev...HRNet: HRNetIIS Web Site Monitoring: A software for monitor a particular web site on IIS, even if its IP is sharing between different web site.Iowa Code Camp: The source code for the Iowa Code Camp website.Leonidas: Leonidas is a virtual tutorLunch 'n Learn: The Lunch 'n Learn web application is an open source ASP.NET MVC application that allows you to setup lunch 'n learn presentations for your team, c...MNT Cryptography: A very simple cryptography classMooiNooi MVC2LINQ2SQL Web Databinder: mvc2linq2sql is a databinder for ASP.NET MVC that make able developer to clean bind object from HTML FORMS to Linq entities. Even 1 to N relations ...MoqBot: MoqBot is an auto mocking library for Moq and Ninject.mtExperience1: hoiMvcPager: MvcPager is a free paging component for ASP.NET MVC web application, it exposes a series of extension methods for using in ASP.NET MVC applications...OCal: OCal is based on object calisthenics to identify code smellsPex Custom Arithmetic Solver: Pex Custom Arithmetic Solver contains a collection of meta-heuristic search algorithms. The goal is to improve Pex's code coverage for code involvi...SetControls: Расширеные контролы для ASP.NET приложений. Полная информация ближе к релизу...shadowrage1597: CTC 195 Game Design classSharePoint Team-Mailer: A SharePoint 2007 solution that defines a generic CustomList for sending e-mails to SharePoint Groups.Sql Share: SQL Share is a collaboration tool used within the science to allow database engineers to work tightly with domain scientists.TechCalendar: Tech Events Calendar ASP.NET project.ZLYScript: A very simple script language compiler.New ReleasesALGLIB: ALGLIB 2.4.0: New ALGLIB release contains: improved versions of several linear algebra algorithms: QR decomposition, matrix inversion, condition number estimatio...AmiBroker Plug-Ins with C#: AmiBroker Plug-Ins v0.0.2: Source codes and a binaryAppFabric Caching UI Admin Tool: AppFabric Caching Beta 2 UI Admin Tool: System Requirements:.NET 4.0 RC AppFabric Caching Beta2 Test On:Win 7 (64x)Autodocs - WCF REST Automatic API Documentation Generator: Autodocs.ServiceModel.Web: This archive contains the reference DLL, instructions and license.Compact Plugs & Compact Injection: Compact Injection and Compact Plugs 1.1 Beta: First release of Compact Plugs (CP). The solution includes a simple example project of CP, called "TestCompactPlugs1". Also some fixes where made ...Console Highlighter: Console Highlighter 0.9 (preview release): Preliminary release.Encrypted Notes: Encrypted Notes 1.3: This is the latest version of Encrypted Notes (1.3). It has an installer - it will create a directory 'CPascoe' in My Documents. The last one was ...Family Tree Analyzer: Version 1.0.2: Family Tree Analyzer Version 1.0.2 This early beta version implements loading a gedcom file and displaying some basic reports. These reports inclu...FRC1103 - FRC Dashboard viewer: 2010 Documentation v0.1: This is my current version of the control system documentation for 2010. It isn't complete, but it has the information required for a custom dashbo...jQuery.cssLess: jQuery.cssLess 0.5 (Even less release): NEW - support for nested special CSS classes (like :hover) MAIN RELEASE This release, code "Even less", is the one that will interpret cssLess wit...MooiNooi MVC2LINQ2SQL Web Databinder: MooiNooi MVC2LINQ2SQL DataBinder: I didn't try this... I just took it off from my project. Please, tell me any problem implementing in your own development and I'll be pleased to h...MvcPager: MvcPager 1.2 for ASP.NET MVC 1.0: MvcPager 1.2 for ASP.NET MVC 1.0Mytrip.Mvc: Mytrip 1.0 preview 1: Article Manager Blog Manager L2S Membership(.NET Framework 3.5) EF Membership(.NET Framework 4) User Manager File Manager Localization Captcha ...NodeXL: Network Overview, Discovery and Exploration for Excel: NodeXL Excel 2007 Template, version 1.0.1.117: The NodeXL Excel 2007 template displays a network graph using edge and vertex lists stored in an Excel 2007 workbook. What's NewThis version adds ...Pex Custom Arithmetic Solver: PexCustomArithmeticSolver: This is the alpha release containing the Alternating Variable Method and Evolution Strategies to try and solve constraints over floating point vari...Scrum Sprint Monitor: v1.0.0.44877: What is new in this release? Major performance increase in animations (up to 50 fps from 2 fps) by replacing DropShadow effect with png bitmaps; ...sELedit: sELedit v1.0b: + Added support for empty strings / wstrings + Fixed: critical bug in configuration files (list 53)sPWadmin: pwAdmin v0.9_nightly: + Fixed: XML editor can now open and save character templates + Added: PWI item name database + Added: Plugin SupportTechCalendar: Events Calendar v.1.0: Initial release.The Silverlight Hyper Video Player [http://slhvp.com]: Beta 2: Beta 2.0 Some fixes from Beta 1, and a couple small enhancements. Intensive testing continues, and I will continue to update the code at least ever...ThreadSafe.Caching: 2010.03.10.1: Updates to the scavanging behaviour since last release. Scavenging will now occur every 30 seconds by default and all objects in the cache will be ...VCC: Latest build, v2.1.30310.0: Automatic drop of latest buildVisual Studio DSite: Email Sender (C++): The same Email Sender program that I but made in visual c plus plus 2008 instead of visual basic 2008.Web Forms MVP: Web Forms MVP CTP7: The release can be considered stable, and is in use behind several high traffic, public websites. It has been marked as a CTP release as it is not ...White Tiger: 0.0.3.1: Now you can load or create files with whatever root element you want *check f or sets file permisionsMost Popular ProjectsMetaSharpWBFS ManagerRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)ASP.NETMicrosoft SQL Server Community & SamplesASP.NET Ajax LibraryMost Active ProjectsUmbraco CMSRawrSDS: Scientific DataSet library and toolsN2 CMSFasterflect - A Fast and Simple Reflection APIjQuery Library for SharePoint Web ServicesBlogEngine.NETFarseer Physics Enginepatterns & practices – Enterprise LibraryCaliburn: An Application Framework for WPF and Silverlight

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  • Workaround for datadude deployment bug - NullReferenceException

    - by jamiet
    I have come across a bug in Visual Studio 2010 Database Projects (aka datadude aka DPro aka Visual Studio Database Development Tools aka Visual Studio Team Edition for Database Professionals aka Juneau aka SQL Server Data Tools) that other people may encounter so, for the purposes of googling, I'm writing this blog post about it. Through my own googling I discovered that a Connect bug had already been raised about it (VS2010 Database project deploy - “SqlDeployTask” task failed unexpectedly, NullReferenceException), and coincidentally enough it was raised by my former colleague Tom Hunter (whom I have mentioned here before as the superhuman Tom Hunter) although it has not (at this time) received a reply from Microsoft. Tom provided a repro, namely that this syntactically valid function definition: CREATE FUNCTION [dbo].[Function1]()RETURNS TABLEASRETURN (    WITH cte AS (    SELECT 1 AS [c1]    FROM [$(Database3)].[dbo].[Table1]   )   SELECT 1 AS [c1]   FROM cte) would produce this nasty unhelpful error upon deployment: C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v10.0\TeamData\Microsoft.Data.Schema.TSqlTasks.targets(120,5): Error MSB4018: The "SqlDeployTask" task failed unexpectedly.System.NullReferenceException: Object reference not set to an instance of an object.   at Microsoft.Data.Schema.Sql.SchemaModel.SqlModelComparerBase.VariableSubstitution(SqlScriptProperty propertyValue, IDictionary`2 variables, Boolean& isChanged)   at Microsoft.Data.Schema.Sql.SchemaModel.SqlModelComparerBase.ArePropertiesEqual(IModelElement source, IModelElement target, ModelPropertyClass propertyClass, ModelComparerConfiguration configuration)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareProperties(IModelElement sourceElement, IModelElement targetElement, ModelComparerConfiguration configuration, ModelComparisonChangeDefinition changes)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareElementsWithoutCompareName(IModelElement sourceElement, IModelElement targetElement, ModelComparerConfiguration configuration, Boolean parentExplicitlyIncluded, Boolean compareElementOnly, ModelComparisonResult result, ModelComparisonChangeDefinition changes)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareElementsWithSameType(IModelElement sourceElement, IModelElement targetElement, ModelComparerConfiguration configuration, ModelComparisonResult result, Boolean ignoreComparingName, Boolean parentExplicitlyIncluded, Boolean compareElementOnly, Boolean compareFromRootElement, ModelComparisonChangeDefinition& changes)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareChildren(IModelElement sourceElement, IModelElement targetElement, ModelComparerConfiguration configuration, Boolean parentExplicitlyIncluded, Boolean compareParentElementOnly, ModelComparisonResult result, ModelComparisonChangeDefinition changes, Boolean isComposing)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareElementsWithoutCompareName(IModelElement sourceElement, IModelElement targetElement, ModelComparerConfiguration configuration, Boolean parentExplicitlyIncluded, Boolean compareElementOnly, ModelComparisonResult result, ModelComparisonChangeDefinition changes)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareElementsWithSameType(IModelElement sourceElement, IModelElement targetElement, ModelComparerConfiguration configuration, ModelComparisonResult result, Boolean ignoreComparingName, Boolean parentExplicitlyIncluded, Boolean compareElementOnly, Boolean compareFromRootElement, ModelComparisonChangeDefinition& changes)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareChildren(IModelElement sourceElement, IModelElement targetElement, ModelComparerConfiguration configuration, Boolean parentExplicitlyIncluded, Boolean compareParentElementOnly, ModelComparisonResult result, ModelComparisonChangeDefinition changes, Boolean isComposing)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareElementsWithoutCompareName(IModelElement sourceElement, IModelElement targetElement, ModelComparerConfiguration configuration, Boolean parentExplicitlyIncluded, Boolean compareElementOnly, ModelComparisonResult result, ModelComparisonChangeDefinition changes)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareElementsWithSameType(IModelElement sourceElement, IModelElement targetElement, ModelComparerConfiguration configuration, ModelComparisonResult result, Boolean ignoreComparingName, Boolean parentExplicitlyIncluded, Boolean compareElementOnly, Boolean compareFromRootElement, ModelComparisonChangeDefinition& changes)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareAllElementsForOneType(ModelElementClass type, ModelComparerConfiguration configuration, ModelComparisonResult result, Boolean compareOrphanedElements)   at Microsoft.Data.Schema.SchemaModel.ModelComparer.CompareStore(ModelStore source, ModelStore target, ModelComparerConfiguration configuration)   at Microsoft.Data.Schema.Build.SchemaDeployment.CompareModels()   at Microsoft.Data.Schema.Build.SchemaDeployment.PrepareBuildPlan()   at Microsoft.Data.Schema.Build.SchemaDeployment.Execute(Boolean executeDeployment)   at Microsoft.Data.Schema.Build.SchemaDeployment.Execute()   at Microsoft.Data.Schema.Tasks.DBDeployTask.Execute()   at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute()   at Microsoft.Build.BackEnd.TaskBuilder.ExecuteInstantiatedTask(ITaskExecutionHost taskExecutionHost, TaskLoggingContext taskLoggingContext, TaskHost taskHost, ItemBucket bucket, TaskExecutionMode howToExecuteTask, Boolean& taskResult)   Done executing task "SqlDeployTask" -- FAILED.  Done building target "DspDeploy" in project "Lloyds.UKTax.DB.UKtax.dbproj" -- FAILED. Done executing task "CallTarget" -- FAILED.Done building target "DBDeploy" in project It turns out there are a certain set of circumstances that need to be met for this error to occur: The object being deployed is an inline function  (may also exist for multistatement and scalar functions - I haven't tested that) That object includes SQLCMD variable references The object has already been deployed successfully Just to reiterate that last bullet point, the error does not occur when you deploy the function for the first time, only on the subsequent deployment.   Luckily I have a direct line into a guy on the development team so I fired off an email on Friday evening and today (Monday) I received a reply back telling me that there is a simple fix, one simply has to remove the parentheses that wrap the SQL statement. So, in the case of Tom's repro, the function definition simpy has to be changed to: CREATE FUNCTION [dbo].[Function1]()RETURNS TABLEASRETURN --(    WITH cte AS (    SELECT 1 AS [c1]    FROM [$(Database3)].[dbo].[Table1]   )   SELECT 1 AS [c1]   FROM cte--) I have commented out the offending parentheses rather than removing them just to emphasize the point. Thereafter the function will deploy fine. I tested this out on my own project this morning and can confirm that this fix does indeed work.   I have been told that the bug CAN be reproduced in the Release Candidate (RC) 0 build of SQL Server Data Tools in SQL Server 2010 so am hoping that a fix makes it in for the Release-To-Manufacturing (RTM) build. Hope this helps @jamiet

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  • Book Review: Oracle ADF Real World Developer’s Guide

    - by Frank Nimphius
    Recently PACKT Publishing published "Oracle ADF Real World Developer’s Guide" by Jobinesh Purushothaman, a product manager in our team. Though already the sixth book dedicated to Oracle ADF, it has a lot of great information in it that none of the previous books covered, making it a safe buy even for those who own the other books published by Oracle Press (McGrwHill) and PACKT Publishing. More than the half of the "Oracle ADF Real World Developer’s Guide" book is dedicated to Oracle ADF Business Components in a depth and clarity that allows you to feel the expertise that Jobinesh gained in this area. If you enjoy Jobinesh blog (http://jobinesh.blogspot.co.uk/) about Oracle ADF, then, no matter what expert you are in Oracle ADF, this book makes you happy as it provides you with detail information you always wished to have. If you are new to Oracle ADF, then this book alone doesn't get you flying, but, if you have some Java background, accelerates your learning big, big, big times. Chapter 1 is an introduction to Oracle ADF and not only explains the layers but also how it compares to plain Java EE solutions (page 13). If you are new to Oracle JDeveloper and ADF, then at the end of this chapter you know how to start JDeveloper and begin your ADF development Chapter 2 starts with what Jobinesh really is good at: ADF Business Components. In this chapter you learn about the architecture ingredients of ADF Business Components: View Objects, View Links, Associations, Entities, Row Sets, Query Collections and Application Modules. This chapter also provides a introduction to ADFBC SDO services, as well as sequence diagrams for what happens when you execute queries or commit updates. Chapter 3 is dedicated to entity objects and  is one of many chapters in this book you will enjoy and never want to miss. Jobinesh explains the artifacts that make up an entity object, how to work with entities and resource bundles, and many advanced topics, including inheritance, change history tracking, custom properties, validation and cursor handling.  Chapter 4 - you guessed it - is all about View objects. Comparable to entities, you learn about the XM files and classes that make a view object, as well as how to define and work with queries. List-of-values, inheritance, polymorphism, bind variables and data filtering are interesting - and important topics that follow. Again the chapter provides helpful sequence diagrams for you to understand what happens internally within a view object. Chapter 5 focuses on advanced view object and entity object topics, like lifecycle callback methods and when you want to override them. This chapter is a good digest of Jobinesh's blog entries (which most ADF developers have in their bookmark list). Really worth reading ! Chapter 6 then is bout Application Modules. Beside of what application modules are, this chapter covers important topics like properties, passivation, activation, application module pooling, how and where to write custom logic. In addition you learn about the AM lifecycle and request sequence. Chapter 7 is about the ADF binding layer. If you are new to Oracle ADF and got lost in the more advanced ADF Business Components chapters, then this chapter is where you get back into the game. In very easy terms, Jobinesh explains what the ADF binding is, how it fits into the JSF request lifecycle and what are the metadata file involved. Chapter 8 then goes into building data bound web user interfaces. In this chapter you get the basics of JavaServer Faces (e.g. managed beans) and learn about the interaction between the JSF UI and the ADF binding layer. Later this chapter provides advanced solutions for working with tree components and list of values. Chapter 9 introduces bounded task flows and ADF controller. This is a chapter you want to read if you are new to ADF of have started. Experts don't find anything new here, which doesn't mean that it is not worth reading it (I for example, enjoyed the controller talk very much) Chapter 10 is an advanced coverage of bounded task flow and talks about contextual events  Chapter 11 is another highlight and explains error handling, trains, transactions and more. I can only recommend you read this chapter. I am aware of many documents that cover exception handling in Oracle ADF (and my Oracle Magazine article for January/February 2013 does the same), but none that covers it in such a great depth. Chapter 12 covers ADF best practices, which is a great round-up of all the tips provided in this book (without Jobinesh to repeat himself). Its all cool stuff that helps you with your ADF projects. In summary, "Oracle ADF Real World Developer’s Guide" by Jobinesh Purushothaman is a great book and addition for all Oracle ADF developers and those who want to become one. Frank

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  • Invalid algorithm specified on Windows 2003 Server only

    - by JL
    I am decoding a file using the following method: string outFileName = zfoFileName.Replace(".zfo", "_tmp.zfo"); FileStream inFile = null; FileStream outFile = null; inFile = File.Open(zfoFileName, FileMode.Open); outFile = File.Create(outFileName); LargeCMS.CMS cms = new LargeCMS.CMS(); cms.Decode(inFile, outFile); This is working fine on my Win 7 dev machine, but on a Windows 2003 server production machine it fails with the following exception: Exception: System.Exception: CryptMsgUpdate error #-2146893816 --- System.ComponentModel.Win32Exception: Invalid algorithm specified --- End of inner exception stack trace --- at LargeCMS.CMS.Decode(FileStream inFile, FileStream outFile) Here are the classes below which I call to do the decoding, if needed I can upload a sample file for decoding, its just strange it works on Win 7, and not on Win2k3 server: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.IO; using System.Security.Cryptography; using System.Security.Cryptography.X509Certificates; using System.Runtime.InteropServices; using System.ComponentModel; namespace LargeCMS { class CMS { // File stream to use in callback function private FileStream m_callbackFile; // Streaming callback function for encoding private Boolean StreamOutputCallback(IntPtr pvArg, IntPtr pbData, int cbData, Boolean fFinal) { // Write all bytes to encoded file Byte[] bytes = new Byte[cbData]; Marshal.Copy(pbData, bytes, 0, cbData); m_callbackFile.Write(bytes, 0, cbData); if (fFinal) { // This is the last piece. Close the file m_callbackFile.Flush(); m_callbackFile.Close(); m_callbackFile = null; } return true; } // Encode CMS with streaming to support large data public void Encode(X509Certificate2 cert, FileStream inFile, FileStream outFile) { // Variables Win32.CMSG_SIGNER_ENCODE_INFO SignerInfo; Win32.CMSG_SIGNED_ENCODE_INFO SignedInfo; Win32.CMSG_STREAM_INFO StreamInfo; Win32.CERT_CONTEXT[] CertContexts = null; Win32.BLOB[] CertBlobs; X509Chain chain = null; X509ChainElement[] chainElements = null; X509Certificate2[] certs = null; RSACryptoServiceProvider key = null; BinaryReader stream = null; GCHandle gchandle = new GCHandle(); IntPtr hProv = IntPtr.Zero; IntPtr SignerInfoPtr = IntPtr.Zero; IntPtr CertBlobsPtr = IntPtr.Zero; IntPtr hMsg = IntPtr.Zero; IntPtr pbPtr = IntPtr.Zero; Byte[] pbData; int dwFileSize; int dwRemaining; int dwSize; Boolean bResult = false; try { // Get data to encode dwFileSize = (int)inFile.Length; stream = new BinaryReader(inFile); pbData = stream.ReadBytes(dwFileSize); // Prepare stream for encoded info m_callbackFile = outFile; // Get cert chain chain = new X509Chain(); chain.Build(cert); chainElements = new X509ChainElement[chain.ChainElements.Count]; chain.ChainElements.CopyTo(chainElements, 0); // Get certs in chain certs = new X509Certificate2[chainElements.Length]; for (int i = 0; i < chainElements.Length; i++) { certs[i] = chainElements[i].Certificate; } // Get context of all certs in chain CertContexts = new Win32.CERT_CONTEXT[certs.Length]; for (int i = 0; i < certs.Length; i++) { CertContexts[i] = (Win32.CERT_CONTEXT)Marshal.PtrToStructure(certs[i].Handle, typeof(Win32.CERT_CONTEXT)); } // Get cert blob of all certs CertBlobs = new Win32.BLOB[CertContexts.Length]; for (int i = 0; i < CertContexts.Length; i++) { CertBlobs[i].cbData = CertContexts[i].cbCertEncoded; CertBlobs[i].pbData = CertContexts[i].pbCertEncoded; } // Get CSP of client certificate key = (RSACryptoServiceProvider)certs[0].PrivateKey; bResult = Win32.CryptAcquireContext( ref hProv, key.CspKeyContainerInfo.KeyContainerName, key.CspKeyContainerInfo.ProviderName, key.CspKeyContainerInfo.ProviderType, 0 ); if (!bResult) { throw new Exception("CryptAcquireContext error #" + Marshal.GetLastWin32Error().ToString(), new Win32Exception(Marshal.GetLastWin32Error())); } // Populate Signer Info struct SignerInfo = new Win32.CMSG_SIGNER_ENCODE_INFO(); SignerInfo.cbSize = Marshal.SizeOf(SignerInfo); SignerInfo.pCertInfo = CertContexts[0].pCertInfo; SignerInfo.hCryptProvOrhNCryptKey = hProv; SignerInfo.dwKeySpec = (int)key.CspKeyContainerInfo.KeyNumber; SignerInfo.HashAlgorithm.pszObjId = Win32.szOID_OIWSEC_sha1; // Populate Signed Info struct SignedInfo = new Win32.CMSG_SIGNED_ENCODE_INFO(); SignedInfo.cbSize = Marshal.SizeOf(SignedInfo); SignedInfo.cSigners = 1; SignerInfoPtr = Marshal.AllocHGlobal(Marshal.SizeOf(SignerInfo)); Marshal.StructureToPtr(SignerInfo, SignerInfoPtr, false); SignedInfo.rgSigners = SignerInfoPtr; SignedInfo.cCertEncoded = CertBlobs.Length; CertBlobsPtr = Marshal.AllocHGlobal(Marshal.SizeOf(CertBlobs[0]) * CertBlobs.Length); for (int i = 0; i < CertBlobs.Length; i++) { Marshal.StructureToPtr(CertBlobs[i], new IntPtr(CertBlobsPtr.ToInt64() + (Marshal.SizeOf(CertBlobs[i]) * i)), false); } SignedInfo.rgCertEncoded = CertBlobsPtr; // Populate Stream Info struct StreamInfo = new Win32.CMSG_STREAM_INFO(); StreamInfo.cbContent = dwFileSize; StreamInfo.pfnStreamOutput = new Win32.StreamOutputCallbackDelegate(StreamOutputCallback); // TODO: CMSG_DETACHED_FLAG // Open message to encode hMsg = Win32.CryptMsgOpenToEncode( Win32.X509_ASN_ENCODING | Win32.PKCS_7_ASN_ENCODING, 0, Win32.CMSG_SIGNED, ref SignedInfo, null, ref StreamInfo ); if (hMsg.Equals(IntPtr.Zero)) { throw new Exception("CryptMsgOpenToEncode error #" + Marshal.GetLastWin32Error().ToString(), new Win32Exception(Marshal.GetLastWin32Error())); } // Process the whole message gchandle = GCHandle.Alloc(pbData, GCHandleType.Pinned); pbPtr = gchandle.AddrOfPinnedObject(); dwRemaining = dwFileSize; dwSize = (dwFileSize < 1024 * 1000 * 100) ? dwFileSize : 1024 * 1000 * 100; while (dwRemaining > 0) { // Update message piece by piece bResult = Win32.CryptMsgUpdate( hMsg, pbPtr, dwSize, (dwRemaining <= dwSize) ? true : false ); if (!bResult) { throw new Exception("CryptMsgUpdate error #" + Marshal.GetLastWin32Error().ToString(), new Win32Exception(Marshal.GetLastWin32Error())); } // Move to the next piece pbPtr = new IntPtr(pbPtr.ToInt64() + dwSize); dwRemaining -= dwSize; if (dwRemaining < dwSize) { dwSize = dwRemaining; } } } finally { // Clean up if (gchandle.IsAllocated) { gchandle.Free(); } if (stream != null) { stream.Close(); } if (m_callbackFile != null) { m_callbackFile.Close(); } if (!CertBlobsPtr.Equals(IntPtr.Zero)) { Marshal.FreeHGlobal(CertBlobsPtr); } if (!SignerInfoPtr.Equals(IntPtr.Zero)) { Marshal.FreeHGlobal(SignerInfoPtr); } if (!hProv.Equals(IntPtr.Zero)) { Win32.CryptReleaseContext(hProv, 0); } if (!hMsg.Equals(IntPtr.Zero)) { Win32.CryptMsgClose(hMsg); } } } // Decode CMS with streaming to support large data public void Decode(FileStream inFile, FileStream outFile) { // Variables Win32.CMSG_STREAM_INFO StreamInfo; Win32.CERT_CONTEXT SignerCertContext; BinaryReader stream = null; GCHandle gchandle = new GCHandle(); IntPtr hMsg = IntPtr.Zero; IntPtr pSignerCertInfo = IntPtr.Zero; IntPtr pSignerCertContext = IntPtr.Zero; IntPtr pbPtr = IntPtr.Zero; IntPtr hStore = IntPtr.Zero; Byte[] pbData; Boolean bResult = false; int dwFileSize; int dwRemaining; int dwSize; int cbSignerCertInfo; try { // Get data to decode dwFileSize = (int)inFile.Length; stream = new BinaryReader(inFile); pbData = stream.ReadBytes(dwFileSize); // Prepare stream for decoded info m_callbackFile = outFile; // Populate Stream Info struct StreamInfo = new Win32.CMSG_STREAM_INFO(); StreamInfo.cbContent = dwFileSize; StreamInfo.pfnStreamOutput = new Win32.StreamOutputCallbackDelegate(StreamOutputCallback); // Open message to decode hMsg = Win32.CryptMsgOpenToDecode( Win32.X509_ASN_ENCODING | Win32.PKCS_7_ASN_ENCODING, 0, 0, IntPtr.Zero, IntPtr.Zero, ref StreamInfo ); if (hMsg.Equals(IntPtr.Zero)) { throw new Exception("CryptMsgOpenToDecode error #" + Marshal.GetLastWin32Error().ToString(), new Win32Exception(Marshal.GetLastWin32Error())); } // Process the whole message gchandle = GCHandle.Alloc(pbData, GCHandleType.Pinned); pbPtr = gchandle.AddrOfPinnedObject(); dwRemaining = dwFileSize; dwSize = (dwFileSize < 1024 * 1000 * 100) ? dwFileSize : 1024 * 1000 * 100; while (dwRemaining > 0) { // Update message piece by piece bResult = Win32.CryptMsgUpdate( hMsg, pbPtr, dwSize, (dwRemaining <= dwSize) ? true : false ); if (!bResult) { throw new Exception("CryptMsgUpdate error #" + Marshal.GetLastWin32Error().ToString(), new Win32Exception(Marshal.GetLastWin32Error())); } // Move to the next piece pbPtr = new IntPtr(pbPtr.ToInt64() + dwSize); dwRemaining -= dwSize; if (dwRemaining < dwSize) { dwSize = dwRemaining; } } // Get signer certificate info cbSignerCertInfo = 0; bResult = Win32.CryptMsgGetParam( hMsg, Win32.CMSG_SIGNER_CERT_INFO_PARAM, 0, IntPtr.Zero, ref cbSignerCertInfo ); if (!bResult) { throw new Exception("CryptMsgGetParam error #" + Marshal.GetLastWin32Error().ToString(), new Win32Exception(Marshal.GetLastWin32Error())); } pSignerCertInfo = Marshal.AllocHGlobal(cbSignerCertInfo); bResult = Win32.CryptMsgGetParam( hMsg, Win32.CMSG_SIGNER_CERT_INFO_PARAM, 0, pSignerCertInfo, ref cbSignerCertInfo ); if (!bResult) { throw new Exception("CryptMsgGetParam error #" + Marshal.GetLastWin32Error().ToString(), new Win32Exception(Marshal.GetLastWin32Error())); } // Open a cert store in memory with the certs from the message hStore = Win32.CertOpenStore( Win32.CERT_STORE_PROV_MSG, Win32.X509_ASN_ENCODING | Win32.PKCS_7_ASN_ENCODING, IntPtr.Zero, 0, hMsg ); if (hStore.Equals(IntPtr.Zero)) { throw new Exception("CertOpenStore error #" + Marshal.GetLastWin32Error().ToString(), new Win32Exception(Marshal.GetLastWin32Error())); } // Find the signer's cert in the store pSignerCertContext = Win32.CertGetSubjectCertificateFromStore( hStore, Win32.X509_ASN_ENCODING | Win32.PKCS_7_ASN_ENCODING, pSignerCertInfo ); if (pSignerCertContext.Equals(IntPtr.Zero)) { throw new Exception("CertGetSubjectCertificateFromStore error #" + Marshal.GetLastWin32Error().ToString(), new Win32Exception(Marshal.GetLastWin32Error())); } // Set message for verifying SignerCertContext = (Win32.CERT_CONTEXT)Marshal.PtrToStructure(pSignerCertContext, typeof(Win32.CERT_CONTEXT)); bResult = Win32.CryptMsgControl( hMsg, 0, Win32.CMSG_CTRL_VERIFY_SIGNATURE, SignerCertContext.pCertInfo ); if (!bResult) { throw new Exception("CryptMsgControl error #" + Marshal.GetLastWin32Error().ToString(), new Win32Exception(Marshal.GetLastWin32Error())); } } finally { // Clean up if (gchandle.IsAllocated) { gchandle.Free(); } if (!pSignerCertContext.Equals(IntPtr.Zero)) { Win32.CertFreeCertificateContext(pSignerCertContext); } if (!pSignerCertInfo.Equals(IntPtr.Zero)) { Marshal.FreeHGlobal(pSignerCertInfo); } if (!hStore.Equals(IntPtr.Zero)) { Win32.CertCloseStore(hStore, Win32.CERT_CLOSE_STORE_FORCE_FLAG); } if (stream != null) { stream.Close(); } if (m_callbackFile != null) { m_callbackFile.Close(); } if (!hMsg.Equals(IntPtr.Zero)) { Win32.CryptMsgClose(hMsg); } } } } } and using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Runtime.InteropServices; using System.Security.Cryptography.X509Certificates; using System.ComponentModel; using System.Security.Cryptography; namespace LargeCMS { class Win32 { #region "CONSTS" public const int X509_ASN_ENCODING = 0x00000001; public const int PKCS_7_ASN_ENCODING = 0x00010000; public const int CMSG_SIGNED = 2; public const int CMSG_DETACHED_FLAG = 0x00000004; public const int AT_KEYEXCHANGE = 1; public const int AT_SIGNATURE = 2; public const String szOID_OIWSEC_sha1 = "1.3.14.3.2.26"; public const int CMSG_CTRL_VERIFY_SIGNATURE = 1; public const int CMSG_CERT_PARAM = 12; public const int CMSG_SIGNER_CERT_INFO_PARAM = 7; public const int CERT_STORE_PROV_MSG = 1; public const int CERT_CLOSE_STORE_FORCE_FLAG = 1; #endregion #region "STRUCTS" [StructLayout(LayoutKind.Sequential)] public struct CRYPT_ALGORITHM_IDENTIFIER { public String pszObjId; BLOB Parameters; } [StructLayout(LayoutKind.Sequential)] public struct CERT_ID { public int dwIdChoice; public BLOB IssuerSerialNumberOrKeyIdOrHashId; } [StructLayout(LayoutKind.Sequential)] public struct CMSG_SIGNER_ENCODE_INFO { public int cbSize; public IntPtr pCertInfo; public IntPtr hCryptProvOrhNCryptKey; public int dwKeySpec; public CRYPT_ALGORITHM_IDENTIFIER HashAlgorithm; public IntPtr pvHashAuxInfo; public int cAuthAttr; public IntPtr rgAuthAttr; public int cUnauthAttr; public IntPtr rgUnauthAttr; public CERT_ID SignerId; public CRYPT_ALGORITHM_IDENTIFIER HashEncryptionAlgorithm; public IntPtr pvHashEncryptionAuxInfo; } [StructLayout(LayoutKind.Sequential)] public struct CERT_CONTEXT { public int dwCertEncodingType; public IntPtr pbCertEncoded; public int cbCertEncoded; public IntPtr pCertInfo; public IntPtr hCertStore; } [StructLayout(LayoutKind.Sequential)] public struct BLOB { public int cbData; public IntPtr pbData; } [StructLayout(LayoutKind.Sequential)] public struct CMSG_SIGNED_ENCODE_INFO { public int cbSize; public int cSigners; public IntPtr rgSigners; public int cCertEncoded; public IntPtr rgCertEncoded; public int cCrlEncoded; public IntPtr rgCrlEncoded; public int cAttrCertEncoded; public IntPtr rgAttrCertEncoded; } [StructLayout(LayoutKind.Sequential)] public struct CMSG_STREAM_INFO { public int cbContent; public StreamOutputCallbackDelegate pfnStreamOutput; public IntPtr pvArg; } #endregion #region "DELEGATES" public delegate Boolean StreamOutputCallbackDelegate(IntPtr pvArg, IntPtr pbData, int cbData, Boolean fFinal); #endregion #region "API" [DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)] public static extern Boolean CryptAcquireContext( ref IntPtr hProv, String pszContainer, String pszProvider, int dwProvType, int dwFlags ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern IntPtr CryptMsgOpenToEncode( int dwMsgEncodingType, int dwFlags, int dwMsgType, ref CMSG_SIGNED_ENCODE_INFO pvMsgEncodeInfo, String pszInnerContentObjID, ref CMSG_STREAM_INFO pStreamInfo ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern IntPtr CryptMsgOpenToDecode( int dwMsgEncodingType, int dwFlags, int dwMsgType, IntPtr hCryptProv, IntPtr pRecipientInfo, ref CMSG_STREAM_INFO pStreamInfo ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern Boolean CryptMsgClose( IntPtr hCryptMsg ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern Boolean CryptMsgUpdate( IntPtr hCryptMsg, Byte[] pbData, int cbData, Boolean fFinal ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern Boolean CryptMsgUpdate( IntPtr hCryptMsg, IntPtr pbData, int cbData, Boolean fFinal ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern Boolean CryptMsgGetParam( IntPtr hCryptMsg, int dwParamType, int dwIndex, IntPtr pvData, ref int pcbData ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern Boolean CryptMsgControl( IntPtr hCryptMsg, int dwFlags, int dwCtrlType, IntPtr pvCtrlPara ); [DllImport("advapi32.dll", SetLastError = true)] public static extern Boolean CryptReleaseContext( IntPtr hProv, int dwFlags ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern IntPtr CertCreateCertificateContext( int dwCertEncodingType, IntPtr pbCertEncoded, int cbCertEncoded ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern Boolean CertFreeCertificateContext( IntPtr pCertContext ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern IntPtr CertOpenStore( int lpszStoreProvider, int dwMsgAndCertEncodingType, IntPtr hCryptProv, int dwFlags, IntPtr pvPara ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern IntPtr CertGetSubjectCertificateFromStore( IntPtr hCertStore, int dwCertEncodingType, IntPtr pCertId ); [DllImport("Crypt32.dll", SetLastError = true)] public static extern IntPtr CertCloseStore( IntPtr hCertStore, int dwFlags ); #endregion } }

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  • Listing common SQL Code Smells.

    - by Phil Factor
    Once you’ve done a number of SQL Code-reviews, you’ll know those signs in the code that all might not be well. These ’Code Smells’ are coding styles that don’t directly cause a bug, but are indicators that all is not well with the code. . Kent Beck and Massimo Arnoldi seem to have coined the phrase in the "OnceAndOnlyOnce" page of www.C2.com, where Kent also said that code "wants to be simple". Bad Smells in Code was an essay by Kent Beck and Martin Fowler, published as Chapter 3 of the book ‘Refactoring: Improving the Design of Existing Code’ (ISBN 978-0201485677) Although there are generic code-smells, SQL has its own particular coding habits that will alert the programmer to the need to re-factor what has been written. See Exploring Smelly Code   and Code Deodorants for Code Smells by Nick Harrison for a grounding in Code Smells in C# I’ve always been tempted by the idea of automating a preliminary code-review for SQL. It would be so useful to trawl through code and pick up the various problems, much like the classic ‘Lint’ did for C, and how the Code Metrics plug-in for .NET Reflector by Jonathan 'Peli' de Halleux is used for finding Code Smells in .NET code. The problem is that few of the standard procedural code smells are relevant to SQL, and we need an agreed list of code smells. Merrilll Aldrich made a grand start last year in his blog Top 10 T-SQL Code Smells.However, I'd like to make a start by discovering if there is a general opinion amongst Database developers what the most important SQL Smells are. One can be a bit defensive about code smells. I will cheerfully write very long stored procedures, even though they are frowned on. I’ll use dynamic SQL occasionally. You can only use them as an aid for your own judgment and it is fine to ‘sign them off’ as being appropriate in particular circumstances. Also, whole classes of ‘code smells’ may be irrelevant for a particular database. The use of proprietary SQL, for example, is only a ‘code smell’ if there is a chance that the database will have to be ported to another RDBMS. The use of dynamic SQL is a risk only with certain security models. As the saying goes,  a CodeSmell is a hint of possible bad practice to a pragmatist, but a sure sign of bad practice to a purist. Plamen Ratchev’s wonderful article Ten Common SQL Programming Mistakes lists some of these ‘code smells’ along with out-and-out mistakes, but there are more. The use of nested transactions, for example, isn’t entirely incorrect, even though the database engine ignores all but the outermost: but it does flag up the possibility that the programmer thinks that nested transactions are supported. If anything requires some sort of general agreement, the definition of code smells is one. I’m therefore going to make this Blog ‘dynamic, in that, if anyone twitters a suggestion with a #SQLCodeSmells tag (or sends me a twitter) I’ll update the list here. If you add a comment to the blog with a suggestion of what should be added or removed, I’ll do my best to oblige. In other words, I’ll try to keep this blog up to date. The name against each 'smell' is the name of the person who Twittered me, commented about or who has written about the 'smell'. it does not imply that they were the first ever to think of the smell! Use of deprecated syntax such as *= (Dave Howard) Denormalisation that requires the shredding of the contents of columns. (Merrill Aldrich) Contrived interfaces Use of deprecated datatypes such as TEXT/NTEXT (Dave Howard) Datatype mis-matches in predicates that rely on implicit conversion.(Plamen Ratchev) Using Correlated subqueries instead of a join   (Dave_Levy/ Plamen Ratchev) The use of Hints in queries, especially NOLOCK (Dave Howard /Mike Reigler) Few or No comments. Use of functions in a WHERE clause. (Anil Das) Overuse of scalar UDFs (Dave Howard, Plamen Ratchev) Excessive ‘overloading’ of routines. The use of Exec xp_cmdShell (Merrill Aldrich) Excessive use of brackets. (Dave Levy) Lack of the use of a semicolon to terminate statements Use of non-SARGable functions on indexed columns in predicates (Plamen Ratchev) Duplicated code, or strikingly similar code. Misuse of SELECT * (Plamen Ratchev) Overuse of Cursors (Everyone. Special mention to Dave Levy & Adrian Hills) Overuse of CLR routines when not necessary (Sam Stange) Same column name in different tables with different datatypes. (Ian Stirk) Use of ‘broken’ functions such as ‘ISNUMERIC’ without additional checks. Excessive use of the WHILE loop (Merrill Aldrich) INSERT ... EXEC (Merrill Aldrich) The use of stored procedures where a view is sufficient (Merrill Aldrich) Not using two-part object names (Merrill Aldrich) Using INSERT INTO without specifying the columns and their order (Merrill Aldrich) Full outer joins even when they are not needed. (Plamen Ratchev) Huge stored procedures (hundreds/thousands of lines). Stored procedures that can produce different columns, or order of columns in their results, depending on the inputs. Code that is never used. Complex and nested conditionals WHILE (not done) loops without an error exit. Variable name same as the Datatype Vague identifiers. Storing complex data  or list in a character map, bitmap or XML field User procedures with sp_ prefix (Aaron Bertrand)Views that reference views that reference views that reference views (Aaron Bertrand) Inappropriate use of sql_variant (Neil Hambly) Errors with identity scope using SCOPE_IDENTITY @@IDENTITY or IDENT_CURRENT (Neil Hambly, Aaron Bertrand) Schemas that involve multiple dated copies of the same table instead of partitions (Matt Whitfield-Atlantis UK) Scalar UDFs that do data lookups (poor man's join) (Matt Whitfield-Atlantis UK) Code that allows SQL Injection (Mladen Prajdic) Tables without clustered indexes (Matt Whitfield-Atlantis UK) Use of "SELECT DISTINCT" to mask a join problem (Nick Harrison) Multiple stored procedures with nearly identical implementation. (Nick Harrison) Excessive column aliasing may point to a problem or it could be a mapping implementation. (Nick Harrison) Joining "too many" tables in a query. (Nick Harrison) Stored procedure returning more than one record set. (Nick Harrison) A NOT LIKE condition (Nick Harrison) excessive "OR" conditions. (Nick Harrison) User procedures with sp_ prefix (Aaron Bertrand) Views that reference views that reference views that reference views (Aaron Bertrand) sp_OACreate or anything related to it (Bill Fellows) Prefixing names with tbl_, vw_, fn_, and usp_ ('tibbling') (Jeremiah Peschka) Aliases that go a,b,c,d,e... (Dave Levy/Diane McNurlan) Overweight Queries (e.g. 4 inner joins, 8 left joins, 4 derived tables, 10 subqueries, 8 clustered GUIDs, 2 UDFs, 6 case statements = 1 query) (Robert L Davis) Order by 3,2 (Dave Levy) MultiStatement Table functions which are then filtered 'Sel * from Udf() where Udf.Col = Something' (Dave Ballantyne) running a SQL 2008 system in SQL 2000 compatibility mode(John Stafford)

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  • Java FAQ: Tudo o que você precisa saber

    - by Bruno.Borges
    Com frequência recebo e-mails de clientes com dúvidas sobre "quando sairá a próxima versão do Java?", ou então "quando vai expirar o Java?" ou ainda "quais as mudanças da próxima versão?". Por isso resolvi escrever aqui um FAQ, respondendo estas dúvidas e muitas outras. Este post estará sempre atualizado, então se você possui alguma dúvida, envie para mim no Twitter @brunoborges. Qual a diferença entre o Oracle JDK e o OpenJDK?O projeto OpenJDK funciona como a implementação de referência Open Source do Java Standard Edition. Empresas como a Oracle, IBM, e Azul Systems suportam e investem no projeto OpenJDK para continuar evoluindo a plataforma Java. O Oracle JDK é baseado no OpenJDK, mas traz outras ferramentas como o Mission Control, e a máquina virtual traz algumas features avançadas como por exemplo o Flight Recorder. Até a versão 6, a Oracle oferecia duas máquinas virtuais: JRockit (BEA) e HotSpot (Sun). A partir da versão 7 a Oracle unificou as máquinas virtuais, e levou as features avançadas do JRockit para dentro da VM HotSpot. Leia também o OpenJDK FAQ. Onde posso obter binários beta Early Access do JDK 7, JDK 8, JDK 9 para testar?A partir do projeto OpenJDK, existe um projeto específico para cada versão do Java. Nestes projetos você pode encontrar binários beta Early Access, além do código-fonte. JDK 6 - http://jdk6.java.net/ JDK 7 - http://jdk7.java.net/ JDK 8 - http://jdk8.java.net/ JDK 9 - http://jdk9.java.net/ Quando acaba o suporte do Oracle Java SE 6, 7, 8? Somente produtos e versões com release oficial são suportados pela Oracle (exemplo: não há suporte para binários beta do JDK 7, JDK 8, ou JDK 9). Existem duas categorias de datas que o usuriário do Java deve estar ciente:  EOPU - End of Public UpdatesMomento em que a Oracle não mais disponibiliza publicamente atualizações Oracle SupportPolítica de suporte da Oracle para produtos, incluindo o Oracle Java SE O Oracle Java SE é um produto e portando os períodos de suporte são regidos pelo Oracle Lifetime Support Policy. Consulte este documento para datas atualizadas e específicas para cada versão do Java. O Oracle Java SE 6 já atingiu EOPU (End of Public Updates) e agora é mantido e atualizado somente para clientes através de contrato comercial de suporte. Para maiores informações, consulte a página sobre Oracle Java SE Support.  O mais importante aqui é você estar ciente sobre as datas de EOPU para as versões do Java SE da Oracle.Consulte a página do Oracle Java SE Support Roadmap e busque nesta página pela tabela com nome Java SE Public Updates. Nela você encontrará a data em que determinada versão do Java irá atingir EOPU. Como funciona o versionamento do Java?Em 2013, a Oracle divulgou um novo esquema de versionamento do Java para facilmente identificar quando é um release CPU e quando é um release LFR, e também para facilitar o planejamento e desenvolvimento de correções e features para futuras versões. CPU - Critical Patch UpdateAtualizações com correções de segurança. Versão será múltipla de 5, ou com soma de 1 para manter o número ímpar. Exemplos: 7u45, 7u51, 7u55. LFR - Limited Feature ReleaseAtualizações com correções de funcionalidade, melhorias de performance, e novos recursos. Versões de números pares múltiplos de 20, com final 0. Exemplos: 7u40, 7u60, 8u20. Qual a data da próxima atualização de segurança (CPU) do Java SE?Lançamentos do tipo CPU são controlados e pré-agendados pela Oracle e se aplicam a todos os produtos, inclusive o Oracle Java SE. Estes releases acontecem a cada 3 meses, sempre na Terça-feira mais próxima do dia 17 dos meses de Janeiro, Abril, Julho, e Outubro. Consulte a página Critical Patch Updates, Security Alerts and Third Party Bulleting para saber das próximas datas. Caso tenha interesse, você pode acompanhar através de recebimentos destes boletins diretamente no seu email. Veja como assinar o Boletim de Segurança da Oracle. Qual a data da próxima atualização de features (LFR) do Java SE?A Oracle reserva o direito de não divulgar estas datas, assim como o faz para todos os seus produtos. Entretanto é possível acompanhar o desenvolvimento da próxima versão pelos sites do projeto OpenJDK. A próxima versão do JDK 7 será o update 60 e binários beta Early Access já estão disponíveis para testes. A próxima versão doJDK 8 será o update 20 e binários beta Early Access já estão disponíveis para testes. Onde posso ver as mudanças e o que foi corrigido para a próxima versão do Java?A Oracle disponibiliza um changelog para cada binário beta Early Access divulgado no portal Java.net. JDK 7 update 60 changelogs JDK 8 update 20 changelogs Quando o Java da minha máquina (ou do meu usuário) vai expirar?Conheçendo o sistema de versionamento do Java e a periodicidade dos releases de CPU, o usuário pode determinar quando que um update do Java irá expirar. De todo modo, a cada novo update, a Oracle já informa quando que este update deverá expirar diretamente no release notes da versão. Por exemplo, no release notes da versão Oracle Java SE 7 update 55, está escrito na seção JRE Expiration Date o seguinte: The JRE expires whenever a new release with security vulnerability fixes becomes available. Critical patch updates, which contain security vulnerability fixes, are announced one year in advance on Critical Patch Updates, Security Alerts and Third Party Bulletin. This JRE (version 7u55) will expire with the release of the next critical patch update scheduled for July 15, 2014. For systems unable to reach the Oracle Servers, a secondary mechanism expires this JRE (version 7u55) on August 15, 2014. After either condition is met (new release becoming available or expiration date reached), the JRE will provide additional warnings and reminders to users to update to the newer version. For more information, see JRE Expiration Date.Ou seja, a versão 7u55 irá expirar com o lançamento do próximo release CPU, pré-agendado para o dia 15 de Julho de 2014. E caso o computador do usuário não possa se comunicar com o servidor da Oracle, esta versão irá expirar forçadamente no dia 15 de Agosto de 2014 (através de um mecanismo embutido na versão 7u55). O usuário não é obrigado a atualizar para versões LFR e portanto, mesmo com o release da versão 7u60, a versão atual 7u55 não irá expirar.Veja o release notes do Oracle Java SE 8 update 5. Encontrei um bug. Como posso reportar bugs ou problemas no Java SE, para a Oracle?Sempre que possível, faça testes com os binários beta antes da versão final ser lançada. Qualquer problema que você encontrar com estes binários beta, por favor descreva o problema através do fórum de Project Feebdack do JDK.Caso você encontre algum problema em uma versão final do Java, utilize o formulário de Bug Report. Importante: bugs reportados por estes sistemas não são considerados Suporte e portanto não há SLA de atendimento. A Oracle reserva o direito de manter o bug público ou privado, e também de informar ou não o usuário sobre o progresso da resolução do problema. Tenho uma dúvida que não foi respondida aqui. Como faço?Se você possui uma pergunta que não foi respondida aqui, envie para bruno.borges_at_oracle.com e caso ela seja pertinente, tentarei responder neste artigo. Para outras dúvidas, entre em contato pelo meu Twitter @brunoborges.

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  • How to build the Darling projrct on Ubuntu 13.10?

    - by mirror27
    The Darling project is an open source Darwin/OS X emulation layer for Linux. I downloaded the source code with git and tried to build it with cmake but it failed. The document says I need these packages: clang 3.1+ GCC 4.6+ (yes, you still need GCC for header files) libkqueue libbsd gnustep-base ("Foundation") gnustep-gui ("Cocoa") gnustep-corebase ("CoreFoundation") libobjc2 libudev openssl libasound libav libgc but I could not find them on apt or in software center. Also cmake showed this result: No build type selected, default to Debug This is a 64-bit build Building ObjC ABI 2 You have called ADD_LIBRARY for library Carbon without any source files. This typically indicates a problem with your CMakeLists.txt file You have called ADD_LIBRARY for library AppKit without any source files. This typically indicates a problem with your CMakeLists.txt file You have called ADD_LIBRARY for library auto without any source files. This typically indicates a problem with your CMakeLists.txt file CMake Error: The following variables are used in this project, but they are set to NOTFOUND. Please set them or make sure they are set and tested correctly in the CMake files: LIBGNUSTEPCOREBASE_INCLUDE_DIR used as include directory in directory /home/mirror/work/darling/darling/src/motool used as include directory in directory /home/mirror/work/darling/darling/src/util used as include directory in directory /home/mirror/work/darling/darling/src/libmach-o used as include directory in directory /home/mirror/work/darling/darling/src/libdyld used as include directory in directory /home/mirror/work/darling/darling/src/dyld used as include directory in directory /home/mirror/work/darling/darling/src/dyld used as include directory in directory /home/mirror/work/darling/darling/src/libSystem used as include directory in directory /home/mirror/work/darling/darling/src/libltdl used as include directory in directory /home/mirror/work/darling/darling/src/Cocoa used as include directory in directory /home/mirror/work/darling/darling/src/libobjcdarwin used as include directory in directory /home/mirror/work/darling/darling/src/CoreFoundation used as include directory in directory /home/mirror/work/darling/darling/src/libncurses used as include directory in directory /home/mirror/work/darling/darling/src/CoreSecurity used as include directory in directory /home/mirror/work/darling/darling/src/CoreServices used as include directory in directory /home/mirror/work/darling/darling/src/ExceptionHandling used as include directory in directory /home/mirror/work/darling/darling/src/IOKit used as include directory in directory /home/mirror/work/darling/darling/src/Foundation used as include directory in directory /home/mirror/work/darling/darling/src/Carbon used as include directory in directory /home/mirror/work/darling/darling/src/CoreVideo used as include directory in directory /home/mirror/work/darling/darling/src/OpenGL used as include directory in directory /home/mirror/work/darling/darling/src/thin used as include directory in directory /home/mirror/work/darling/darling/src/thin used as include directory in directory /home/mirror/work/darling/darling/src/libstdc++darwin LIBKQUEUE_INCLUDE_DIR used as include directory in directory /home/mirror/work/darling/darling/src/motool used as include directory in directory /home/mirror/work/darling/darling/src/util used as include directory in directory /home/mirror/work/darling/darling/src/libmach-o used as include directory in directory /home/mirror/work/darling/darling/src/libdyld used as include directory in directory /home/mirror/work/darling/darling/src/dyld used as include directory in directory /home/mirror/work/darling/darling/src/dyld used as include directory in directory /home/mirror/work/darling/darling/src/libSystem used as include directory in directory /home/mirror/work/darling/darling/src/libltdl used as include directory in directory /home/mirror/work/darling/darling/src/Cocoa used as include directory in directory /home/mirror/work/darling/darling/src/libobjcdarwin used as include directory in directory /home/mirror/work/darling/darling/src/CoreFoundation used as include directory in directory /home/mirror/work/darling/darling/src/libncurses used as include directory in directory /home/mirror/work/darling/darling/src/CoreSecurity used as include directory in directory /home/mirror/work/darling/darling/src/CoreServices used as include directory in directory /home/mirror/work/darling/darling/src/ExceptionHandling used as include directory in directory /home/mirror/work/darling/darling/src/IOKit used as include directory in directory /home/mirror/work/darling/darling/src/Foundation used as include directory in directory /home/mirror/work/darling/darling/src/Carbon used as include directory in directory /home/mirror/work/darling/darling/src/CoreVideo used as include directory in directory /home/mirror/work/darling/darling/src/OpenGL used as include directory in directory /home/mirror/work/darling/darling/src/thin used as include directory in directory /home/mirror/work/darling/darling/src/thin used as include directory in directory /home/mirror/work/darling/darling/src/libstdc++darwin LIBOBJC2_INCLUDE_DIR used as include directory in directory /home/mirror/work/darling/darling/src/motool used as include directory in directory /home/mirror/work/darling/darling/src/util used as include directory in directory /home/mirror/work/darling/darling/src/libmach-o used as include directory in directory /home/mirror/work/darling/darling/src/libdyld used as include directory in directory /home/mirror/work/darling/darling/src/dyld used as include directory in directory /home/mirror/work/darling/darling/src/dyld used as include directory in directory /home/mirror/work/darling/darling/src/libSystem used as include directory in directory /home/mirror/work/darling/darling/src/libltdl used as include directory in directory /home/mirror/work/darling/darling/src/Cocoa used as include directory in directory /home/mirror/work/darling/darling/src/libobjcdarwin used as include directory in directory /home/mirror/work/darling/darling/src/CoreFoundation used as include directory in directory /home/mirror/work/darling/darling/src/libncurses used as include directory in directory /home/mirror/work/darling/darling/src/CoreSecurity used as include directory in directory /home/mirror/work/darling/darling/src/CoreServices used as include directory in directory /home/mirror/work/darling/darling/src/ExceptionHandling used as include directory in directory /home/mirror/work/darling/darling/src/IOKit used as include directory in directory /home/mirror/work/darling/darling/src/Foundation used as include directory in directory /home/mirror/work/darling/darling/src/Carbon used as include directory in directory /home/mirror/work/darling/darling/src/CoreVideo used as include directory in directory /home/mirror/work/darling/darling/src/OpenGL used as include directory in directory /home/mirror/work/darling/darling/src/thin used as include directory in directory /home/mirror/work/darling/darling/src/thin used as include directory in directory /home/mirror/work/darling/darling/src/libstdc++darwin Configuring incomplete, errors occurred! How can I build the Darling project?

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  • Jdbc - Connect remote Mysql Database error

    - by Guilherme Ruiz
    I'm using JDBC to connect my program to a MySQL database. I already put the port number and yes, my database have permission to access. When i use localhost work perfectly, but when i try connect to a remote MySQL database, show this error on console. java.lang.ExceptionInInitializerError Caused by: java.lang.NumberFormatException: null at java.lang.Integer.parseInt(Integer.java:454) at java.lang.Integer.parseInt(Integer.java:527) at serial.BDArduino.<clinit>(BDArduino.java:25) Exception in thread "main" Java Result: 1 CONSTRUÍDO COM SUCESSO (tempo total: 1 segundo) Thank you in Advance ! MAIN CODE /* * To change this template, choose Tools | Templates * and open the template in the editor. */ package serial; import gnu.io.CommPort; import gnu.io.CommPortIdentifier; import gnu.io.SerialPort; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import javax.swing.JFrame; import javax.swing.JOptionPane; /** * * @author Ruiz */ public class BDArduino extends JFrame { static boolean connected = false; static int aux_sql8 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin8")); static int aux_sql2 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin2")); CommPort commPort = null; SerialPort serialPort = null; InputStream inputStream = null; static OutputStream outputStream = null; String comPortNum = "COM10"; int baudRate = 9600; int[] intArray = {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13}; /** * Creates new form ArduinoTest */ public BDArduino() { //super("Arduino Test App"); initComponents(); } class Escrita extends Thread { private int i; public void run() { while (true) { System.out.println("Número :" + i++); } } } //public void actionPerformed(ActionEvent e) { // String arg = e.getActionCommand(); public static void writeData(int a) throws IOException { outputStream.write(a); } public void action(String arg) { System.out.println(arg); Object[] msg = {"Baud Rate: ", "9600", "COM Port #: ", "COM10"}; if (arg == "connect") { if (connected == false) { new BDArduino.ConnectionMaker().start(); } else { closeConnection(); } } if (arg == "disconnect") { serialPort.close(); closeConnection(); } if (arg == "p2") { System.out.print("Pin #2\n"); try { outputStream.write(intArray[0]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p3") { System.out.print("Pin #3\n"); try { outputStream.write(intArray[1]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p4") { System.out.print("Pin #4\n"); try { outputStream.write(intArray[2]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p5") { System.out.print("Pin #5\n"); try { outputStream.write(intArray[3]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p6") { System.out.print("Pin #6\n"); try { outputStream.write(intArray[4]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p7") { System.out.print("Pin #7\n"); try { outputStream.write(intArray[5]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p8") { System.out.print("Pin #8\n"); try { outputStream.write(intArray[6]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p9") { System.out.print("Pin #9\n"); try { outputStream.write(intArray[7]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p10") { System.out.print("Pin #10\n"); try { outputStream.write(intArray[8]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p11") { System.out.print("Pin #11\n"); try { outputStream.write(intArray[9]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p12") { System.out.print("Pin #12\n"); try { outputStream.write(intArray[10]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p13") { System.out.print("Pin #12\n"); try { outputStream.write(intArray[11]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } } //******************************************************* //Arduino Connection *************************************** //****************************************************** void closeConnection() { try { outputStream.close(); } catch (Exception ex) { ex.printStackTrace(); String cantCloseConnectionMessage = "Can't Close Connection!"; JOptionPane.showMessageDialog(null, cantCloseConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } connected = false; System.out.print("\nDesconectado\n"); String disconnectedConnectionMessage = "Desconectado!"; JOptionPane.showMessageDialog(null, disconnectedConnectionMessage, "Desconectado", JOptionPane.INFORMATION_MESSAGE); }//end closeConnection() void connect() throws Exception { String portName = comPortNum; CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName); if (portIdentifier.isCurrentlyOwned()) { System.out.println("Error: Port is currently in use"); String portInUseConnectionMessage = "Port is currently in use!\nTry Again Later..."; JOptionPane.showMessageDialog(null, portInUseConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } else { commPort = portIdentifier.open(this.getClass().getName(), 2000); if (commPort instanceof SerialPort) { serialPort = (SerialPort) commPort; serialPort.setSerialPortParams(baudRate, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE); outputStream = serialPort.getOutputStream(); } else { System.out.println("Error: Only serial ports are handled "); String onlySerialConnectionMessage = "Serial Ports ONLY!"; JOptionPane.showMessageDialog(null, onlySerialConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } }//end else //wait some time try { Thread.sleep(300); } catch (InterruptedException ie) { } }//end connect //******************************************************* //*innerclasses****************************************** //******************************************************* public class ConnectionMaker extends Thread { public void run() { //try to make a connection try { connect(); } catch (Exception ex) { ex.printStackTrace(); System.out.print("ERROR: Cannot connect!"); String cantConnectConnectionMessage = "Cannot Connect!\nCheck the connection settings\nand/or your configuration\nand try again!"; JOptionPane.showMessageDialog(null, cantConnectConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } //show status serialPort.notifyOnDataAvailable(true); connected = true; //send ack System.out.print("\nConnected\n"); String connectedConnectionMessage = "Conectado!"; JOptionPane.showMessageDialog(null, connectedConnectionMessage, "Conectado", JOptionPane.INFORMATION_MESSAGE); }//end run }//end ConnectionMaker /** * This method is called from within the constructor to initialize the form. * WARNING: Do NOT modify this code. The content of this method is always * regenerated by the Form Editor. */ @SuppressWarnings("unchecked") // <editor-fold defaultstate="collapsed" desc="Generated Code"> private void initComponents() { btnp2 = new javax.swing.JButton(); btncon = new javax.swing.JButton(); btndesc = new javax.swing.JButton(); btnp3 = new javax.swing.JButton(); btnp4 = new javax.swing.JButton(); btnp5 = new javax.swing.JButton(); btnp9 = new javax.swing.JButton(); btnp6 = new javax.swing.JButton(); btnp7 = new javax.swing.JButton(); btnp8 = new javax.swing.JButton(); btn13 = new javax.swing.JButton(); btnp10 = new javax.swing.JButton(); btnp11 = new javax.swing.JButton(); btnp12 = new javax.swing.JButton(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); btnp2.setText("2"); btnp2.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp2MouseClicked(evt); } }); btncon.setText("Conectar"); btncon.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnconMouseClicked(evt); } }); btndesc.setText("Desconectar"); btndesc.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btndescMouseClicked(evt); } }); btnp3.setText("3"); btnp3.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp3MouseClicked(evt); } }); btnp4.setText("4"); btnp4.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp4MouseClicked(evt); } }); btnp5.setText("5"); btnp5.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp5MouseClicked(evt); } }); btnp9.setText("9"); btnp9.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp9MouseClicked(evt); } }); btnp6.setText("6"); btnp6.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp6MouseClicked(evt); } }); btnp7.setText("7"); btnp7.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp7MouseClicked(evt); } }); btnp8.setText("8"); btnp8.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp8MouseClicked(evt); } }); btn13.setText("13"); btn13.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btn13MouseClicked(evt); } }); btnp10.setText("10"); btnp10.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp10MouseClicked(evt); } }); btnp11.setText("11"); btnp11.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp11MouseClicked(evt); } }); btnp12.setText("12"); btnp12.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp12MouseClicked(evt); } }); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(20, 20, 20) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false) .addGroup(layout.createSequentialGroup() .addComponent(btncon) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) .addComponent(btndesc)) .addGroup(layout.createSequentialGroup() .addComponent(btnp6, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp7, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp8, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp9, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGroup(layout.createSequentialGroup() .addComponent(btnp10, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp11, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp12, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btn13, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGroup(layout.createSequentialGroup() .addComponent(btnp2, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp3, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp4, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp5, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))) .addContainerGap(20, Short.MAX_VALUE)) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addContainerGap() .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(btncon) .addComponent(btndesc)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 20, Short.MAX_VALUE) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(btnp2) .addComponent(btnp3) .addComponent(btnp4) .addComponent(btnp5)) .addGap(18, 18, 18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(btnp6) .addComponent(btnp7) .addComponent(btnp8) .addComponent(btnp9)) .addGap(18, 18, 18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(btnp10) .addComponent(btnp11) .addComponent(btnp12) .addComponent(btn13)) .addGap(22, 22, 22)) ); pack(); }// </editor-fold> private void btnp2MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p2"); } private void btnconMouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("connect"); } private void btndescMouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("disconnect"); } private void btnp3MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p3"); } private void btnp4MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p4"); } private void btnp5MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here action("p5"); } private void btnp9MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p9"); } private void btnp6MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p6"); } private void btnp7MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p7"); } private void btnp8MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p8"); } private void btn13MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p13"); } private void btnp10MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p10"); } private void btnp11MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p11"); } private void btnp12MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p12"); } /** * @param args the command line arguments */ public static void main(String args[]) throws IOException { /* Set the Nimbus look and feel */ //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) "> /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel. * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ try { for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) { if ("Nimbus".equals(info.getName())) { javax.swing.UIManager.setLookAndFeel(info.getClassName()); break; } } } catch (Exception e) { } //</editor-fold> /* Create and display the form */ java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new BDArduino().setVisible(true); } }); //} while (true) { // int sql8 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin8")); if (connected == true && sql8 != aux_sql8) { aux_sql8 = sql8; if(sql8 == 1){ writeData(2); }else{ writeData(3); } } int sql2 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin2")); if (connected == true && sql2 != aux_sql2) { aux_sql2 = sql2; if(sql2 == 1){ writeData(4); }else{ writeData(5); } } try { Thread.sleep(500); } catch (InterruptedException e) { e.printStackTrace(); } } } // Variables declaration - do not modify private javax.swing.JButton btn13; private javax.swing.JButton btncon; private javax.swing.JButton btndesc; private javax.swing.JButton btnp10; private javax.swing.JButton btnp11; private javax.swing.JButton btnp12; private javax.swing.JButton btnp2; private javax.swing.JButton btnp3; private javax.swing.JButton btnp4; private javax.swing.JButton btnp5; private javax.swing.JButton btnp6; private javax.swing.JButton btnp7; private javax.swing.JButton btnp8; private javax.swing.JButton btnp9; // End of variables declaration }

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  • SSH error: Permission denied, please try again

    - by Kamal
    I am new to ubuntu. Hence please forgive me if the question is too simple. I have a ubuntu server setup using amazon ec2 instance. I need to connect my desktop (which is also a ubuntu machine) to the ubuntu server using SSH. I have installed open-ssh in ubuntu server. I need all systems of my network to connect the ubuntu server using SSH (no need to connect through pem or pub keys). Hence opened SSH port 22 for my static IP in security groups (AWS). My SSHD-CONFIG file is: # Package generated configuration file # See the sshd_config(5) manpage for details # What ports, IPs and protocols we listen for Port 22 # Use these options to restrict which interfaces/protocols sshd will bind to #ListenAddress :: #ListenAddress 0.0.0.0 Protocol 2 # HostKeys for protocol version 2 HostKey /etc/ssh/ssh_host_rsa_key HostKey /etc/ssh/ssh_host_dsa_key HostKey /etc/ssh/ssh_host_ecdsa_key #Privilege Separation is turned on for security UsePrivilegeSeparation yes # Lifetime and size of ephemeral version 1 server key KeyRegenerationInterval 3600 ServerKeyBits 768 # Logging SyslogFacility AUTH LogLevel INFO # Authentication: LoginGraceTime 120 PermitRootLogin yes StrictModes yes RSAAuthentication yes PubkeyAuthentication yes #AuthorizedKeysFile %h/.ssh/authorized_keys # Don't read the user's ~/.rhosts and ~/.shosts files IgnoreRhosts yes # For this to work you will also need host keys in /etc/ssh_known_hosts RhostsRSAAuthentication no # similar for protocol version 2 HostbasedAuthentication no # Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication #IgnoreUserKnownHosts yes # To enable empty passwords, change to yes (NOT RECOMMENDED) PermitEmptyPasswords no # Change to yes to enable challenge-response passwords (beware issues with # some PAM modules and threads) ChallengeResponseAuthentication no # Change to no to disable tunnelled clear text passwords #PasswordAuthentication yes # Kerberos options #KerberosAuthentication no #KerberosGetAFSToken no #KerberosOrLocalPasswd yes #KerberosTicketCleanup yes # GSSAPI options #GSSAPIAuthentication no #GSSAPICleanupCredentials yes X11Forwarding yes X11DisplayOffset 10 PrintMotd no PrintLastLog yes TCPKeepAlive yes #UseLogin no #MaxStartups 10:30:60 #Banner /etc/issue.net # Allow client to pass locale environment variables AcceptEnv LANG LC_* Subsystem sftp /usr/lib/openssh/sftp-server # Set this to 'yes' to enable PAM authentication, account processing, # and session processing. If this is enabled, PAM authentication will # be allowed through the ChallengeResponseAuthentication and # PasswordAuthentication. Depending on your PAM configuration, # PAM authentication via ChallengeResponseAuthentication may bypass # the setting of "PermitRootLogin without-password". # If you just want the PAM account and session checks to run without # PAM authentication, then enable this but set PasswordAuthentication # and ChallengeResponseAuthentication to 'no'. UsePAM yes Through webmin (Command shell), I have created a new user named 'senthil' and added this new user to 'sudo' group. sudo adduser -y senthil sudo adduser senthil sudo I tried to login using this new user 'senthil' in 'webmin'. I was able to login successfully. When I tried to connect ubuntu server from my terminal through SSH, ssh senthil@SERVER_IP It asked me to enter password. After the password entry, it displayed: Permission denied, please try again. On some research I realized that, I need to monitor my server's auth log for this. I got the following error in my auth log (/var/log/auth.log) Jul 2 09:38:07 ip-192-xx-xx-xxx sshd[3037]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=MY_CLIENT_IP user=senthil Jul 2 09:38:09 ip-192-xx-xx-xxx sshd[3037]: Failed password for senthil from MY_CLIENT_IP port 39116 ssh2 When I tried to debug using: ssh -v senthil@SERVER_IP OpenSSH_5.9p1 Debian-5ubuntu1, OpenSSL 1.0.1 14 Mar 2012 debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 19: Applying options for * debug1: Connecting to SERVER_IP [SERVER_IP] port 22. debug1: Connection established. debug1: identity file {MY-WORKSPACE}/.ssh/id_rsa type 1 debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048 debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048 debug1: identity file {MY-WORKSPACE}/.ssh/id_rsa-cert type -1 debug1: identity file {MY-WORKSPACE}/.ssh/id_dsa type -1 debug1: identity file {MY-WORKSPACE}/.ssh/id_dsa-cert type -1 debug1: identity file {MY-WORKSPACE}/.ssh/id_ecdsa type -1 debug1: identity file {MY-WORKSPACE}/.ssh/id_ecdsa-cert type -1 debug1: Remote protocol version 2.0, remote software version OpenSSH_5.8p1 Debian-7ubuntu1 debug1: match: OpenSSH_5.8p1 Debian-7ubuntu1 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_5.9p1 Debian-5ubuntu1 debug1: SSH2_MSG_KEXINIT sent debug1: SSH2_MSG_KEXINIT received debug1: kex: server->client aes128-ctr hmac-md5 none debug1: kex: client->server aes128-ctr hmac-md5 none debug1: sending SSH2_MSG_KEX_ECDH_INIT debug1: expecting SSH2_MSG_KEX_ECDH_REPLY debug1: Server host key: ECDSA {SERVER_HOST_KEY} debug1: Host 'SERVER_IP' is known and matches the ECDSA host key. debug1: Found key in {MY-WORKSPACE}/.ssh/known_hosts:1 debug1: ssh_ecdsa_verify: signature correct debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug1: SSH2_MSG_NEWKEYS received debug1: Roaming not allowed by server debug1: SSH2_MSG_SERVICE_REQUEST sent debug1: SSH2_MSG_SERVICE_ACCEPT received debug1: Authentications that can continue: password debug1: Next authentication method: password senthil@SERVER_IP's password: debug1: Authentications that can continue: password Permission denied, please try again. senthil@SERVER_IP's password: For password, I have entered the same value which I normally use for 'ubuntu' user. Can anyone please guide me where the issue is and suggest some solution for this issue?

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  • Parallel LINQ - PLINQ

    - by nmarun
    Turns out now with .net 4.0 we can run a query like a multi-threaded application. Say you want to query a collection of objects and return only those that meet certain conditions. Until now, we basically had one ‘control’ that iterated over all the objects in the collection, checked the condition on each object and returned if it passed. We obviously agree that if we can ‘break’ this task into smaller ones, assign each task to a different ‘control’ and ask all the controls to do their job - in-parallel, the time taken the finish the entire task will be much lower. Welcome to PLINQ. Let’s take some examples. I have the following method that uses our good ol’ LINQ. 1: private static void Linq(int lowerLimit, int upperLimit) 2: { 3: // populate an array with int values from lowerLimit to the upperLimit 4: var source = Enumerable.Range(lowerLimit, upperLimit); 5:  6: // Start a timer 7: Stopwatch stopwatch = new Stopwatch(); 8: stopwatch.Start(); 9:  10: // set the expectation => build the expression tree 11: var evenNumbers =   from num in source 12: where IsDivisibleBy(num, 2) 13: select num; 14: 15: // iterate over and print the returned items 16: foreach (var number in evenNumbers) 17: { 18: Console.WriteLine(string.Format("** {0}", number)); 19: } 20:  21: stopwatch.Stop(); 22:  23: // check the metrics 24: Console.WriteLine(String.Format("Elapsed {0}ms", stopwatch.ElapsedMilliseconds)); 25: } I’ve added comments for the major steps, but the only thing I want to talk about here is the IsDivisibleBy() method. I know I could have just included the logic directly in the where clause. I called a method to add ‘delay’ to the execution of the query - to simulate a loooooooooong operation (will be easier to compare the results). 1: private static bool IsDivisibleBy(int number, int divisor) 2: { 3: // iterate over some database query 4: // to add time to the execution of this method; 5: // the TableB has around 10 records 6: for (int i = 0; i < 10; i++) 7: { 8: DataClasses1DataContext dataContext = new DataClasses1DataContext(); 9: var query = from b in dataContext.TableBs select b; 10: 11: foreach (var row in query) 12: { 13: // Do NOTHING (wish my job was like this) 14: } 15: } 16:  17: return number % divisor == 0; 18: } Now, let’s look at how to modify this to PLINQ. 1: private static void Plinq(int lowerLimit, int upperLimit) 2: { 3: // populate an array with int values from lowerLimit to the upperLimit 4: var source = Enumerable.Range(lowerLimit, upperLimit); 5:  6: // Start a timer 7: Stopwatch stopwatch = new Stopwatch(); 8: stopwatch.Start(); 9:  10: // set the expectation => build the expression tree 11: var evenNumbers = from num in source.AsParallel() 12: where IsDivisibleBy(num, 2) 13: select num; 14:  15: // iterate over and print the returned items 16: foreach (var number in evenNumbers) 17: { 18: Console.WriteLine(string.Format("** {0}", number)); 19: } 20:  21: stopwatch.Stop(); 22:  23: // check the metrics 24: Console.WriteLine(String.Format("Elapsed {0}ms", stopwatch.ElapsedMilliseconds)); 25: } That’s it, this is now in PLINQ format. Oh and if you haven’t found the difference, look line 11 a little more closely. You’ll see an extension method ‘AsParallel()’ added to the ‘source’ variable. Couldn’t be more simpler right? So this is going to improve the performance for us. Let’s test it. So in my Main method of the Console application that I’m working on, I make a call to both. 1: static void Main(string[] args) 2: { 3: // set lower and upper limits 4: int lowerLimit = 1; 5: int upperLimit = 20; 6: // call the methods 7: Console.WriteLine("Calling Linq() method"); 8: Linq(lowerLimit, upperLimit); 9: 10: Console.WriteLine(); 11: Console.WriteLine("Calling Plinq() method"); 12: Plinq(lowerLimit, upperLimit); 13:  14: Console.ReadLine(); // just so I get enough time to read the output 15: } YMMV, but here are the results that I got:    It’s quite obvious from the above results that the Plinq() method is taking considerably less time than the Linq() version. I’m sure you’ve already noticed that the output of the Plinq() method is not in order. That’s because, each of the ‘control’s we sent to fetch the results, reported with values as and when they obtained them. This is something about parallel LINQ that one needs to remember – the collection cannot be guaranteed to be undisturbed. This could be counted as a negative about PLINQ (emphasize ‘could’). Nevertheless, if we want the collection to be sorted, we can use a SortedSet (.net 4.0) or build our own custom ‘sorter’. Either way we go, there’s a good chance we’ll end up with a better performance using PLINQ. And there’s another negative of PLINQ (depending on how you see it). This is regarding the CPU cycles. See the usage for Linq() method (used ResourceMonitor): I have dual CPU’s and see the height of the peak in the bottom two blocks and now compare to what happens when I run the Plinq() method. The difference is obvious. Higher usage, but for a shorter duration (width of the peak). Both these points make sense in both cases. Linq() runs for a longer time, but uses less resources whereas Plinq() runs for a shorter time and consumes more resources. Even after knowing all these, I’m still inclined towards PLINQ. PLINQ rocks! (no hard feelings LINQ)

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  • Thank You for a Great Welcome for Oracle GoldenGate 11g Release 2

    - by Irem Radzik
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Yesterday morning we had two launch webcasts for Oracle GoldenGate 11g Release 2. I had the pleasure to present, as well as moderate the Q&A panels in both of these webcasts. Both events had hundreds of live attendees, sending us over 150 questions. Even though we left 30 minutes for Q&A, it was not nearly enough time to address for all the insightful questions our audience sent. Our product management team and I really appreciate the interaction we had yesterday and we are starting to respond back with outstanding questions today. Oracle GoldenGate’s new release launch also had great welcome from the media. You can find the links for various articles on the new release below: ITBusinessEdge Oracle Embraces Cross-Platform Data Integration Information Week: Oracle Real-Time Advance Taps Compressed Data Integration Developer News, Oracle GoldenGate Adds Deeper Oracle Integration, Extends Real-Time Performance CIO, Oracle GoldenGate Buddies Up with Sibling Software DBTA, Real-Time Data Integration: Oracle GoldenGate 11g Release 2 Now Available CBR Oracle unveils GoldenGate 11g Release 2 real-time data integration application In this blog, I want to address some of the frequently asked questions that came up during the webcasts. You can find the top questions and their answers along with related resources below. We will continue to address frequently asked questions via future blogs. Q: Will the new Integrated Capture for Oracle Database replace the Classic Capture? If not, which one do I use when? A: No, Classic Capture will be around for long time. Core platform specific features, bug fixes, and patches will be available for both Capture processes.Oracle Database specific features will be only available in the Integrated Capture. The Integrated Capture for Oracle Database is an option for users that need to capture data from compressed tables or need support for XML data types, XA on RAC. Users who don’t leverage these features should continue to use our Classic Capture. For more information on Oracle GoldenGate 11g Release 2 I recommend to check out the White paper: Oracle GoldenGate 11gR2 New Features as well as other technical white papers we have on OTN.                                                         For those of you coming to OpenWorld, please attend the related session: Extracting Data in Oracle GoldenGate Integrated Capture Mode, Monday Oct 1st 1:45pm Moscone South – 102 to learn more about this new feature. Q: What is new in Conflict Detection and Resolution? And how does it work? A: There are now pre-built functions to identify the conditions under which an error occurs and how to handle the record when the condition occurs. Error conditions handled include inserts into a target table where the row already exists, updates or deletes to target table rows that exist, but the original source data (before columns) do not match the existing data in the target row, and updates or deletes where the row does not exist in the target database table.Foreach of these conditions a method to handle the error is specified.  Please check out our recent blog on this topic and the White paper: Oracle GoldenGate 11gR2 New Features white paper.  Also, for those attending OpenWorld please attend the session: Best Practices for Conflict Detection and Resolution in Oracle GoldenGate for Active/Active-  Wednesday Oct 3rd  3:30pm Mascone 3000 Q: Does Oracle GoldenGate Veridata and the Management Pack require additional licenses, or is it incorporated with the GoldenGate license? A: Oracle GoldenGate Veridata and Oracle Management Pack for Oracle GoldenGate are additional products and require separate licenses. Please check out Oracle's price list here. Q: Does GoldenGate - Oracle Enterprise Manager Plug-in require additional license? A: Oracle Enterprise Manager Plug-in is included in the Oracle Management Pack for Oracle GoldenGate license, which is separate from Oracle GoldenGate license. There is no separate license for the Enterprise Manager Plug-in by itself. Oracle GoldenGate Monitor, Oracle GoldenGate Director, and Enterprise Manager Plug-in are included in the Management Pack for Oracle GoldenGate license. Please check out Management Pack for Oracle GoldenGate data sheet for more info on this product bundle. Q: Is Oracle GoldenGate replacing Oracle Streams product? A: Oracle GoldenGate is the strategic data replication product. Therefore, Oracle Streams will continue to be supported, but will not be actively enhanced. Rather, the best elements of Oracle Streams will be added to Oracle GoldenGate. Conflict management is one of them and with the latest release Oracle GoldenGate has a more advanced conflict management offering. Current customers depending on Oracle Streams will continue to be fully supported. Q: How is Oracle GoldenGate different than Oracle Data Integrator? A: Oracle Data Integrator is designed for fast bulk data movement and transformation between heterogeneous systems, while GoldenGate is designed for real-time movement of transactions between heterogeneous systems. These two products are completely complementary where GoldenGate provides low-impact real-time change data capture and delivery to a staging area on the target. And Oracle Data Integrator transforms this data and loads the DW tables. In fact, Oracle Data Integrator integrates with GoldenGate to use GoldenGate’s Capture process as one option for its CDC mechanism. We have several customers that deployed GoldenGate and ODI together to feed real-time data to their data warehousing solutions. Please also check out Oracle Data Integrator Changed Data Capture with Oracle GoldenGate Data Sheet (PDF). Thank you again very much for welcoming Oracle GoldenGate 11g Release 2 and stay in touch with us for more exciting news, updates, and events.

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  • GLSL Atmospheric Scattering Issue

    - by mtf1200
    I am attempting to use Sean O'Neil's shaders to accomplish atmospheric scattering. For now I am just using SkyFromSpace and GroundFromSpace. The atmosphere works fine but the planet itself is just a giant dark sphere with a white blotch that follows the camera. I think the problem might rest in the "v3Attenuation" variable as when this is removed the sphere is show (albeit without scattering). Here is the vertex shader. Thanks for the time! uniform mat4 g_WorldViewProjectionMatrix; uniform mat4 g_WorldMatrix; uniform vec3 m_v3CameraPos; // The camera's current position uniform vec3 m_v3LightPos; // The direction vector to the light source uniform vec3 m_v3InvWavelength; // 1 / pow(wavelength, 4) for the red, green, and blue channels uniform float m_fCameraHeight; // The camera's current height uniform float m_fCameraHeight2; // fCameraHeight^2 uniform float m_fOuterRadius; // The outer (atmosphere) radius uniform float m_fOuterRadius2; // fOuterRadius^2 uniform float m_fInnerRadius; // The inner (planetary) radius uniform float m_fInnerRadius2; // fInnerRadius^2 uniform float m_fKrESun; // Kr * ESun uniform float m_fKmESun; // Km * ESun uniform float m_fKr4PI; // Kr * 4 * PI uniform float m_fKm4PI; // Km * 4 * PI uniform float m_fScale; // 1 / (fOuterRadius - fInnerRadius) uniform float m_fScaleDepth; // The scale depth (i.e. the altitude at which the atmosphere's average density is found) uniform float m_fScaleOverScaleDepth; // fScale / fScaleDepth attribute vec4 inPosition; vec3 v3ELightPos = vec3(g_WorldMatrix * vec4(m_v3LightPos, 1.0)); vec3 v3ECameraPos= vec3(g_WorldMatrix * vec4(m_v3CameraPos, 1.0)); const int nSamples = 2; const float fSamples = 2.0; varying vec4 color; float scale(float fCos) { float x = 1.0 - fCos; return m_fScaleDepth * exp(-0.00287 + x*(0.459 + x*(3.83 + x*(-6.80 + x*5.25)))); } void main(void) { gl_Position = g_WorldViewProjectionMatrix * inPosition; // Get the ray from the camera to the vertex and its length (which is the far point of the ray passing through the atmosphere) vec3 v3Pos = vec3(g_WorldMatrix * inPosition); vec3 v3Ray = v3Pos - v3ECameraPos; float fFar = length(v3Ray); v3Ray /= fFar; // Calculate the closest intersection of the ray with the outer atmosphere (which is the near point of the ray passing through the atmosphere) float B = 2.0 * dot(m_v3CameraPos, v3Ray); float C = m_fCameraHeight2 - m_fOuterRadius2; float fDet = max(0.0, B*B - 4.0 * C); float fNear = 0.5 * (-B - sqrt(fDet)); // Calculate the ray's starting position, then calculate its scattering offset vec3 v3Start = m_v3CameraPos + v3Ray * fNear; fFar -= fNear; float fDepth = exp((m_fInnerRadius - m_fOuterRadius) / m_fScaleDepth); float fCameraAngle = dot(-v3Ray, v3Pos) / fFar; float fLightAngle = dot(v3ELightPos, v3Pos) / fFar; float fCameraScale = scale(fCameraAngle); float fLightScale = scale(fLightAngle); float fCameraOffset = fDepth*fCameraScale; float fTemp = (fLightScale + fCameraScale); // Initialize the scattering loop variables float fSampleLength = fFar / fSamples; float fScaledLength = fSampleLength * m_fScale; vec3 v3SampleRay = v3Ray * fSampleLength; vec3 v3SamplePoint = v3Start + v3SampleRay * 0.5; // Now loop through the sample rays vec3 v3FrontColor = vec3(0.0, 0.0, 0.0); vec3 v3Attenuate; for(int i=0; i<nSamples; i++) { float fHeight = length(v3SamplePoint); float fDepth = exp(m_fScaleOverScaleDepth * (m_fInnerRadius - fHeight)); float fScatter = fDepth*fTemp - fCameraOffset; v3Attenuate = exp(-fScatter * (m_v3InvWavelength * m_fKr4PI + m_fKm4PI)); v3FrontColor += v3Attenuate * (fDepth * fScaledLength); v3SamplePoint += v3SampleRay; } vec3 first = v3FrontColor * (m_v3InvWavelength * m_fKrESun + m_fKmESun); vec3 secondary = v3Attenuate; color = vec4((first + vec3(0.25,0.25,0.25) * secondary), 1.0); // ^^ that color is passed to the frag shader and is used as the gl_FragColor } Here is also an image of the problem image

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  • Why are pieces of my HTML showing up on the page and breaking it? Is it PHP related?

    - by Jason Rhodes
    I've been building a site in PHP, HTML, CSS, and using a healthy dose of jQuery javascript. The site looks absolutely fine on my Mac browsers, but for some reason, when my client uses PC Safari, she's seeing strange bits of my HTML show up on the page. Here are some (small) screenshot examples: Figure 1: This one is just a closing </li> tag that should've been on the Media li element. Not much harm done, but strange. Figure 2: Here this was part of <div class='submenu'> and since the div tag didn't render properly, the entire contents of that div don't get styled correctly by CSS. Figure 3: This last example shows what should have been <a class='top current' href=... but for some reason half of the HTML tag stops being rendered and just gets printed out. So the rest of that list menu is completely broken. Here's the code from the header.php file itself. The main navigation section (seen in the screenshots) is further down, marked by a line of asterisks if you want to skip there. <?php // Setting up location variables if(isset($_GET['page'])) { $page = Page::find_by_slug($_GET['page']); } elseif(isset($_GET['post'])) { $page = Page::find_by_id(4); } else { $page = Page::find_by_id(1); } $post = isset($_GET['post']) ? Blogpost::find_by_slug($_GET['post']) : false; $front = $page->id == 1 ? true : false; $buildblog = $page->id == 4 ? true : false; $eventpage = $page->id == 42 ? true : false; // Setting up content edit variables $edit = isset($_GET['edit']) ? true : false; $preview = isset($_GET['preview']) ? true : false; // Finding page slug value $pageslug = $page->get_slug($loggedIn); ?> <!DOCTYPE html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title> <?php if(!$post) { if($page->id != 1) { echo $page->title." | "; } echo $database->site_name(); } elseif($post) { echo "BuildBlog | ".$post->title; } ?> </title> <link href="<?php echo SITE_URL; ?>/styles/style.css" media="all" rel="stylesheet" /> <?php include(SITE_ROOT."/scripts/myJS.php"); ?> </head> <body class=" <?php if($loggedIn) { echo "logged"; } else { echo "public"; } if($front) { echo " front"; } ?>"> <?php $previewslug = str_replace("&edit", "", $pageslug); ?> <?php if($edit) { echo "<form id='editPageForm' action='?page={$previewslug}&preview' method='post'>"; } ?> <?php if($edit && !$preview) : // Edit original ?> <div id="admin_meta_nav" class="admin_meta_nav"> <ul class="center nolist"> <li class="title">Edit</li> <li class="cancel"><a class="cancel" href="?page=<?php echo $pageslug; ?>&cancel">Cancel</a></li> <li class="save"><input style='position: relative; z-index: 500' class='save' type="submit" name="newpreview" value="Preview" /></li> <li class="publish"><input style='position: relative; z-index: 500' class='publish button' type="submit" name="publishPreview" value="Publish" /></li> </ul> </div> <?php elseif($preview && !$edit) : // Preview your edits ?> <div id="admin_meta_nav" class="admin_meta_nav"> <ul class="center nolist"> <li class="title">Preview</li> <li class="cancel"><a class="cancel" href="?page=<?php echo $pageslug; ?>&cancel">Cancel</a></li> <li class="save"><a class="newpreview" href="?page=<?php echo $pageslug; ?>&preview&edit">Continue Editing</a></li> <li class="publish"><a class="publish" href="?page=<?php echo $pageslug; ?>&publishLastPreview">Publish</a></li> </ul> </div> <?php elseif($preview && $edit) : // Return to preview and continue editing ?> <div id="admin_meta_nav" class="admin_meta_nav"> <ul class="center nolist"> <li class="title">Edit Again</li> <li class="cancel"><a class="cancel" href="?page=<?php echo $pageslug; ?>&cancel">Cancel</a></li> <li class="save"><input style='position: relative; z-index: 500' class='save button' type="submit" name="newpreview" value="Preview" /></li> <li class="publish"><input style='position: relative; z-index: 500' class='publish button' type="submit" name="publishPreview" value="Publish" /></li> </ul> </div> <?php else : ?> <div id="meta_nav" class="meta_nav"> <ul class="center nolist"> <li><a href="login.php?logout">Logout</a></li> <li><a href="<?php echo SITE_URL; ?>/admin">Admin</a></li> <li><a href="<?php if($front) { echo "admin/?admin=frontpage"; } elseif($event || $eventpage) { echo "admin/?admin=events"; } elseif($buildblog) { if($post) { echo "admin/editpost.php?post={$post->id}"; } else { echo "admin/?admin=blog"; } } else { echo "?page=".$pageslug."&edit"; } ?>">Edit Mode</a></li> <li><a href="<?php echo SITE_URL; ?>/?page=donate">Donate</a></li> <li><a href="<?php echo SITE_URL; ?>/?page=calendar">Calendar</a></li> </ul> <div class="clear"></div> </div> <?php endif; ?> <div id="public_meta_nav" class="public_meta_nav"> <div class="center"> <ul class="nolist"> <li><a href="<?php echo SITE_URL; ?>/?page=donate">Donate</a></li> <li><a href="<?php echo SITE_URL; ?>/?page=calendar">Calendar</a></li> </ul> <div class="clear"></div> </div> </div> * Main Navigation Section, as seen in screenshots above, starts here ** <div class="header"> <div class="center"> <a class="front_logo" href="<?php echo SITE_URL; ?>"><?php echo $database->site_name(); ?></a> <ul class="nolist main_nav"> <?php $tops = Page::get_top_pages(); $topcount = 1; foreach($tops as $top) { $current = $top->id == $topID ? true : false; $title = $top->title == "Front Page" ? "Home" : ucwords($top->title); $url = ($top->title == "Front Page" || !$top->get_slug($loggedIn)) ? SITE_URL : SITE_URL . "/?page=".$top->get_slug($loggedIn); if(isset($_GET['post']) && $top->id == 1) { $current = false; } if(isset($_GET['post']) && $top->id == 4) { $current = true; } echo "<li"; if($topcount > 3) { echo " class='right'"; } echo "><a class='top"; if($current) { echo " current"; } echo "' href='{$url}'>{$title}</a>"; if($children = Page::get_children($top->id)) { echo "<div class='submenu'>"; echo "<div class='corner-helper'></div>"; foreach($children as $child) { echo "<ul class='nolist level1"; if(!$subchildren = Page::get_children($child->id)) { echo " nochildren"; } echo "'>"; $title = ucwords($child->title); $url = !$child->get_slug($loggedIn) ? SITE_URL : SITE_URL . "/?page=".$child->get_slug($loggedIn); if($child->has_published() || $loggedIn) { echo "<li><a class='title' href='{$url}'>{$title}</a>"; if($subchildren = Page::get_children($child->id)) { echo "<ul class='nolist level2'>"; foreach($subchildren as $subchild) { if($subchild->has_published() || $loggedIn) { $title = ucwords($subchild->title); $url = !$subchild->get_slug($loggedIn) ? SITE_URL : SITE_URL . "/?page=".$subchild->get_slug($loggedIn); echo "<li><a href='{$url}'>{$title}</a>"; } } echo "</ul>"; } echo "</li>"; } echo "</ul>"; } echo "</div>"; } echo "</li>"; $topcount++; } ?> </ul> <div class="clear"></div> </div> </div> <div id="mediaLibraryPopup" class="mediaLibraryPopup"> <h3>Media Library</h3> <ul class="box nolist"></ul> <div class="clear"></div> <a href="#" class="cancel">Cancel</a> </div> <div class="main_content"> Does anyone have any idea why the PC Safari browser would be breaking things up like this? I'm assuming it's PHP related but I cannot figure out why it would do that.

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  • C#: LINQ vs foreach - Round 1.

    - by James Michael Hare
    So I was reading Peter Kellner's blog entry on Resharper 5.0 and its LINQ refactoring and thought that was very cool.  But that raised a point I had always been curious about in my head -- which is a better choice: manual foreach loops or LINQ?    The answer is not really clear-cut.  There are two sides to any code cost arguments: performance and maintainability.  The first of these is obvious and quantifiable.  Given any two pieces of code that perform the same function, you can run them side-by-side and see which piece of code performs better.   Unfortunately, this is not always a good measure.  Well written assembly language outperforms well written C++ code, but you lose a lot in maintainability which creates a big techncial debt load that is hard to offset as the application ages.  In contrast, higher level constructs make the code more brief and easier to understand, hence reducing technical cost.   Now, obviously in this case we're not talking two separate languages, we're comparing doing something manually in the language versus using a higher-order set of IEnumerable extensions that are in the System.Linq library.   Well, before we discuss any further, let's look at some sample code and the numbers.  First, let's take a look at the for loop and the LINQ expression.  This is just a simple find comparison:       // find implemented via LINQ     public static bool FindViaLinq(IEnumerable<int> list, int target)     {         return list.Any(item => item == target);     }         // find implemented via standard iteration     public static bool FindViaIteration(IEnumerable<int> list, int target)     {         foreach (var i in list)         {             if (i == target)             {                 return true;             }         }           return false;     }   Okay, looking at this from a maintainability point of view, the Linq expression is definitely more concise (8 lines down to 1) and is very readable in intention.  You don't have to actually analyze the behavior of the loop to determine what it's doing.   So let's take a look at performance metrics from 100,000 iterations of these methods on a List<int> of varying sizes filled with random data.  For this test, we fill a target array with 100,000 random integers and then run the exact same pseudo-random targets through both searches.                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     Any         10       26          0.00046             30.00%     Iteration   10       20          0.00023             -     Any         100      116         0.00201             18.37%     Iteration   100      98          0.00118             -     Any         1000     1058        0.01853             16.78%     Iteration   1000     906         0.01155             -     Any         10,000   10,383      0.18189             17.41%     Iteration   10,000   8843        0.11362             -     Any         100,000  104,004     1.8297              18.27%     Iteration   100,000  87,941      1.13163             -   The LINQ expression is running about 17% slower for average size collections and worse for smaller collections.  Presumably, this is due to the overhead of the state machine used to track the iterators for the yield returns in the LINQ expressions, which seems about right in a tight loop such as this.   So what about other LINQ expressions?  After all, Any() is one of the more trivial ones.  I decided to try the TakeWhile() algorithm using a Count() to get the position stopped like the sample Pete was using in his blog that Resharper refactored for him into LINQ:       // Linq form     public static int GetTargetPosition1(IEnumerable<int> list, int target)     {         return list.TakeWhile(item => item != target).Count();     }       // traditionally iterative form     public static int GetTargetPosition2(IEnumerable<int> list, int target)     {         int count = 0;           foreach (var i in list)         {             if(i == target)             {                 break;             }               ++count;         }           return count;     }   Once again, the LINQ expression is much shorter, easier to read, and should be easier to maintain over time, reducing the cost of technical debt.  So I ran these through the same test data:                       List<T> On 100,000 Iterations     Method      Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile   10       41          0.00041             128%     Iteration   10       18          0.00018             -     TakeWhile   100      171         0.00171             88%     Iteration   100      91          0.00091             -     TakeWhile   1000     1604        0.01604             94%     Iteration   1000     825         0.00825             -     TakeWhile   10,000   15765       0.15765             92%     Iteration   10,000   8204        0.08204             -     TakeWhile   100,000  156950      1.5695              92%     Iteration   100,000  81635       0.81635             -     Wow!  I expected some overhead due to the state machines iterators produce, but 90% slower?  That seems a little heavy to me.  So then I thought, well, what if TakeWhile() is not the right tool for the job?  The problem is TakeWhile returns each item for processing using yield return, whereas our for-loop really doesn't care about the item beyond using it as a stop condition to evaluate. So what if that back and forth with the iterator state machine is the problem?  Well, we can quickly create an (albeit ugly) lambda that uses the Any() along with a count in a closure (if a LINQ guru knows a better way PLEASE let me know!), after all , this is more consistent with what we're trying to do, we're trying to find the first occurence of an item and halt once we find it, we just happen to be counting on the way.  This mostly matches Any().       // a new method that uses linq but evaluates the count in a closure.     public static int TakeWhileViaLinq2(IEnumerable<int> list, int target)     {         int count = 0;         list.Any(item =>             {                 if(item == target)                 {                     return true;                 }                   ++count;                 return false;             });         return count;     }     Now how does this one compare?                         List<T> On 100,000 Iterations     Method         Size     Total (ms)  Per Iteration (ms)  % Slower     TakeWhile      10       41          0.00041             128%     Any w/Closure  10       23          0.00023             28%     Iteration      10       18          0.00018             -     TakeWhile      100      171         0.00171             88%     Any w/Closure  100      116         0.00116             27%     Iteration      100      91          0.00091             -     TakeWhile      1000     1604        0.01604             94%     Any w/Closure  1000     1101        0.01101             33%     Iteration      1000     825         0.00825             -     TakeWhile      10,000   15765       0.15765             92%     Any w/Closure  10,000   10802       0.10802             32%     Iteration      10,000   8204        0.08204             -     TakeWhile      100,000  156950      1.5695              92%     Any w/Closure  100,000  108378      1.08378             33%     Iteration      100,000  81635       0.81635             -     Much better!  It seems that the overhead of TakeAny() returning each item and updating the state in the state machine is drastically reduced by using Any() since Any() iterates forward until it finds the value we're looking for -- for the task we're attempting to do.   So the lesson there is, make sure when you use a LINQ expression you're choosing the best expression for the job, because if you're doing more work than you really need, you'll have a slower algorithm.  But this is true of any choice of algorithm or collection in general.     Even with the Any() with the count in the closure it is still about 30% slower, but let's consider that angle carefully.  For a list of 100,000 items, it was the difference between 1.01 ms and 0.82 ms roughly in a List<T>.  That's really not that bad at all in the grand scheme of things.  Even running at 90% slower with TakeWhile(), for the vast majority of my projects, an extra millisecond to save potential errors in the long term and improve maintainability is a small price to pay.  And if your typical list is 1000 items or less we're talking only microseconds worth of difference.   It's like they say: 90% of your performance bottlenecks are in 2% of your code, so over-optimizing almost never pays off.  So personally, I'll take the LINQ expression wherever I can because they will be easier to read and maintain (thus reducing technical debt) and I can rely on Microsoft's development to have coded and unit tested those algorithm fully for me instead of relying on a developer to code the loop logic correctly.   If something's 90% slower, yes, it's worth keeping in mind, but it's really not until you start get magnitudes-of-order slower (10x, 100x, 1000x) that alarm bells should really go off.  And if I ever do need that last millisecond of performance?  Well then I'll optimize JUST THAT problem spot.  To me it's worth it for the readability, speed-to-market, and maintainability.

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  • Towards an F# .NET Reflector add-in

    - by CliveT
    When I had the opportunity to spent some time during Red Gate's recent "down tools" week on a project of my choice, the obvious project was an F# add-in for Reflector . To be honest, this was a bit of a misnomer as the amount of time in the designated week for coding was really less than three days, so it was always unlikely that very much progress would be made in such a small amount of time (and that certainly proved to be the case), but I did learn some things from the experiment. Like lots of problems, one useful technique is to take examples, get them to work, and then generalise to get something that works across the board. Unfortunately, I didn't have enough time to do the last stage. The obvious first step is to take a few function definitions, starting with the obvious hello world, moving on to a non-recursive function and finishing with the ubiquitous recursive Fibonacci function. let rec printMessage message  =     printfn  message let foo x  =    (x + 1) let rec fib x  =     if (x >= 2) then (fib (x - 1) + fib (x - 2)) else 1 The major problem in decompiling these simple functions is that Reflector has an in-memory object model that is designed to support object-oriented languages. In particular it has a return statement that allows function bodies to finish early. I used some of the in-built functionality to take the IL and produce an in-memory object model for the language, but then needed to write a transformer to push the return statements to the top of the tree to make it easy to render the code into a functional language. This tree transform works in some scenarios, but not in others where we simply regenerate code that looks more like CPS style. The next thing to get working was library level bindings of values where these values are calculated at runtime. let x = [1 ; 2 ; 3 ; 4] let y = List.map  (fun x -> foo x) x The way that this is translated into a set of classes for the underlying platform means that the code needs to follow references around, from the property exposing the calculated value to the class in which the code for generating the value is embedded. One of the strongest selling points of functional languages is the algebraic datatypes, which allow definitions via standard mathematical-style inductive definitions across the union cases. type Foo =     | Something of int     | Nothing type 'a Foo2 =     | Something2 of 'a     | Nothing2 Such a definition is compiled into a number of classes for the cases of the union, which all inherit from a class representing the type itself. It wasn't too hard to get such a de-compilation happening in the cases I tried. What did I learn from this? Firstly, that there are various bits of functionality inside Reflector that it would be useful for us to allow add-in writers to access. In particular, there are various implementations of the Visitor pattern which implement algorithms such as calculating the number of references for particular variables, and which perform various substitutions which could be more generally useful to add-in writers. I hope to do something about this at some point in the future. Secondly, when you transform a functional language into something that runs on top of an object-based platform, you lose some fidelity in the representation. The F# compiler leaves attributes in place so that tools can tell which classes represent classes from the source program and which are there for purposes of the implementation, allowing the decompiler to regenerate these constructs again. However, decompilation technology is a long way from being able to take unannotated IL and transform it into a program in a different language. For a simple function definition, like Fibonacci, I could write a simple static function and have it come out in F# as the same function, but it would be practically impossible to take a mass of class definitions and have a decompiler translate it automatically into an F# algebraic data type. What have we got out of this? Some data on the feasibility of implementing an F# decompiler inside Reflector, though it's hard at the moment to say how long this would take to do. The work we did is included the 6.5 EAP for Reflector that you can get from the EAP forum. All things considered though, it was a useful way to gain more familiarity with the process of writing an add-in and understand difficulties other add-in authors might experience. If you'd like to check out a video of Down Tools Week, click here.

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  • In C what is the difference between null and a new line character? Guys help please [migrated]

    - by Siddhartha Gurjala
    Whats the conceptual difference and similarity between NULL and a newline character i.e between '\0' and '\n' Explain their relevance for both integer and character data type variables and arrays? For reference here is an example snippets of a program to read and write a 2d char array PROGRAM CODE 1: int main() { char sort(),stuname(),swap(),(*p)(),(*q)(); int n; p=stuname; q=swap; printf("Let the number of students in the class be \n"); scanf("%d",&n); fflush(stdin); sort(p,q,n); return 0; } char sort(p1,q1,n1) char (*p1)(),(*q1)(); int n1; { (*p1)(n1); (*q1)(); } char stuname(int nos) // number of students { char name[nos][256]; int i,j; printf("Reading names of %d students started--->\n\n",nos); name[0][0]='k'; //initialising as non NULL charecter for(i=0;i<nos;i++) // nos=number of students { printf("Give name of student %d\n",i); for(j=0;j<256;j++) { scanf("%c",&name[i][j]); if(name[i][j]=='\n') { name[i][j]='\0'; j=257; } } } printf("\n\nWriting student names:\n\n"); for(i=0;i<nos;i++) { for(j=0;j<256&&name[i][j]!='\0';j++) { printf("%c",name[i][j]); } printf("\n"); } } char swap() { printf("Will swap shortly after getting clarity on scanf and %c"); } The above code is working good where as the same logic given with slight diff is not giving appropriate output. Here's the code PROGRAM CODE 2: #include<stdio.h> int main() { char sort(),stuname(),swap(),(*p)(),(*q)(); int n; p=stuname; q=swap; printf("Let the number of students in the class be \n"); scanf("%d",&n); fflush(stdin); sort(p,q,n); return 0; } char sort(p1,q1,n1) char (*p1)(),(*q1)(); int n1; { (*p1)(n1); (*q1)(); } char stuname(int nos) // number of students { char name[nos][256]; int i,j; printf("Reading names of %d students started--->\n\n",nos); name[0][0]='k'; //initialising as non NULL charecter for(i=0;i<nos;i++) // nos=number of students { printf("Give name of student %d\n",i); ***for(j=0;j<256&&name[i][j]!='\0';j++)*** { scanf("%c",&name[i][j]); /*if(name[i][j]=='\n') { name[i][j]='\0'; j=257; }*/ } } printf("\n\nWriting student names:\n\n"); for(i=0;i<nos;i++) { for(j=0;j<256&&name[i][j]!='\0';j++) { printf("%c",name[i][j]); } printf("\n"); } } char swap() { printf("Will swap shortly after getting clarity on scanf and %c"); } Here one more instance of same program not giving proper output given below PROGRAM CODE 3: #include<stdio.h> int main() { char sort(),stuname(),swap(),(*p)(),(*q)(); int n; p=stuname; q=swap; printf("Let the number of students in the class be \n"); scanf("%d",&n); fflush(stdin); sort(p,q,n); return 0; } char sort(p1,q1,n1) char (*p1)(),(*q1)(); int n1; { (*p1)(n1); (*q1)(); } char stuname(int nos) // number of students { char name[nos][256]; int i,j; printf("Reading names of %d students started--->\n\n",nos); name[0][0]='k'; //initialising as non NULL charecter for(i=0;i<nos;i++) // nos=number of students { printf("Give name of student %d\n",i); ***for(j=0;j<256&&name[i][j]!='\n';j++)*** { scanf("%c",&name[i][j]); /*if(name[i][j]=='\n') { name[i][j]='\0'; j=257; }*/ } name[i][i]='\0'; } printf("\n\nWriting student names:\n\n"); for(i=0;i<nos;i++) { for(j=0;j<256&&name[i][j]!='\0';j++) { printf("%c",name[i][j]); } printf("\n"); } } char swap() { printf("Will swap shortly after getting clarity on scanf and %c"); } Why the program code 2 and program code 3 are not working as expected as that of the code 1?

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  • CodePlex Daily Summary for Monday, May 17, 2010

    CodePlex Daily Summary for Monday, May 17, 2010New Projects.NET Essentials Course: .NET Essentials course @ Telerik Academy Training project for the studentsAU/NZ Office 2010 Launch Demos: The AU/NZ Office 2010 Launch Demos are a collection of code samples that were used as part of the Office/SharePoint 2010 launch parties in Australi...CybennyCMS: Very simple CMS system for building sites with ASP.NET with templates for lay-out, content pages with only html content and a xml file for the site...essionPIM: essionPIMGIStance: A library for finding "nearest neighbor" among an in-memory set of positions, in C# and F#. A radius must be specified for making a meaningful s...IP Informer: IP Informer is IP Informer.Kurumsal Ofis Paketi: Kurumsal Ofis Paketi (KOP), Microsoft Ofis 2010 ürünleri için geliştirilmiş eklenti yazılımıdır. KOP, Word ve Excel’de bulunan işlevlerinin genişle...Mockup to XAML: Convert Balsamiq Mockups to XAML. This project supports BMML mockup control conversion using plugins. A standard set of controls are included wit...Open XML Validator: This WPF app give you a brief resume about errors in your Open XML documents.Paint.NET Bulk Image Processor: PDNBulkUpdater is a plug-in for Paint.NET that allows you to efficiently perform operations such as resizing and converting multiple images at the ...PiPiBugNet: PiPiBugNet是一套全新的开源Bug管理系统Roleplay character generator: The roleplay character generator allows the creation of characters for different roleplaying gamesSharePoint User Search WebParts: This project contains SharePoint webparts which provide advanced search configuration and experience for SharePoint 2007. It will be upgrade in few...Spodi: Spodi is created on 22-04-2010TfsPolicyPack: This project will provide a few checkin policies for VS 2010.vccodesandobx: vccodesandobxvccodesandobxvccodesandobxWhiteNile: test project using codeplexNew ReleasesAnimeStore.Net: 1.0.3.0: Build 1.0.3.0 Changes Move some functionality to features (MEF) Filter / Search functionality. Anime hard-copy records storage (e.g Disk Storage ...AU/NZ Office 2010 Launch Demos: Twitter map web part: This is the main twitter map web part download, see the Twitter Map web part page for all the information.Blueset Studio Opensource Projects: 推来: 稳定版本BUtil: BUtil 5.0 Alpha2: The initial implementation of multitasking (except ghost)CassiniDev - Cassini 3.5/4.0 Developers Edition: CassiniDev 3.5.1 and 4.0.1 beta: Beta 2 is released here: url http://cassinidev.codeplex.com/releases/view/45456 New in CassiniDev v3.5.1.0/v4.0.1.0 Added .Net 4 / VS10 build. ...CBM-Command: 2010-05-16: Release Notes - 2010-05-16New Features New navigation options: Page Up, Page Down, Top of Directory, Bottom of Directory. See documentation (http:...CCNet Conditional Plugin: CCNet Conditional for CCNet 1.5: A (quick) build of the plugin for CCNet 1.5 to fix the 17365 bug reported by Beakster. This also adds a new condition "timeCondition"CybennyCMS: Cybenny CMS beta 1: The first beta. Includes a small demo site.Data Extracting SDK: Data Extracting SDK v.1.1 RTM: RTM version of Data Extracting SDK.Duckworth Lewis Professional Edition Calculator: DLcalc 2.0: This software can perform all D/L calculations 100% accurately. From version 2.0 onwards, tables for par scores can also be produced.EPiServer CMS Page Type Builder: Page Type Builder 1.2: Release notes can be found in this blog post.Floe IRC Client: Floe IRC Client 2010-05 R5: - Many new context menu options for @s - Ability to select multiple users in the nick list for some operations (kick, ban) - Bunch of minor bug fix...Graffiti CMS Events Plugin: Version 1.0.1: Minor update to previous version to fix bug where deleted posts were still showing in the calendar.Microsoft Research Boogie: 2010-05-16: Binary release of Boogie and Dafny. (Note, Chalice is not pre-built as part of this binary release. 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Comp...Team Foundation Server Administration Tool: 2.0: TFS Administration Tool 2.0 TFS Administration Tool 2.0 is built on top of the Team Foundation Server 2008 object model and in order to connect to...The Ping Master: v0.9.0.0: Installer for The Ping Master binariesUseful Office Macros: All Macro Downloads: Please find above the downloads related to this project. Each Excel Workbook below works independently of the others, so you only need to download...VCC: Latest build, v2.1.30516.0: Automatic drop of latest buildVisual Studio DSite: Advanced Digital Board Game (Visual C++ 2008): An advanced digital board game made in visual c 2008.YUI Compressor Custom Tool for Visual Studio: YUI Compressor Custom Tool Full Version: Version 1.0 The following changes have been made: Merged classes to automatically sense if the target file is Javascript or CSS. 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