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• The best way to separate admin functionality from a public site?

  - by AndrewO

  I'm working on a site that's grown both in terms of user-base and functionality to the point where it's becoming evident that some of the admin tasks should be separate from the public website. I was wondering what the best way to do this would be. For example, the site has a large social component to it, and a public sales interface. But at the same time, there's back office tasks, bulk upload processing, dashboards (with long running queries), and customer relations tools in the admin section that I would like to not be effected by spikes in public traffic (or effect the public-facing response time). The site is running on a fairly standard Rails/MySQL/Linux stack, but I think this is more of an architecture problem than an implementation one: mainly, how does one keep the data and business logic in sync between these different applications? Some strategies that I'm evaluating: 1) Create a slave database of the public facing database on another machine. Extract out all of the model and library code so that it can be shared between the applications. Create new controllers and views for the admin interfaces. I have limited experience with replication and am not even sure that it's supposed to be used this way (most of the time I've seen it, it's been for scaling out the read capabilities of the same application, rather than having multiple different ones). I'm also worried about the potential for latency issues if the slave is not on the same network. 2) Create new more task/department-specific applications and use a message oriented middleware to integrate them. I read Enterprise Integration Patterns awhile back and they seemed to advocate this for distributed systems. (Alternatively, in some cases the basic Rails-style RESTful API functionality might suffice.) But, I have nightmares about data synchronization issues and the massive re-architecting that this would entail. 3) Some mixture of the two. For example, the only public information necessary for some of the back office tasks is a read-only completion time or status. Would it make sense to have that on a completely separate system and send the data to public? Meanwhile, the user/group admin functionality would be run on a separate system sharing the database? The downside is, this seems to keep many of the concerns I have with the first two, especially the re-architecting. I'm sure the answers are going to be highly dependent on a site's specific needs, but I'd love to hear success (or failure) stories.

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• Recommendations for a C++ polymorphic, seekable, binary I/O interface

  - by Trevor Robinson

  I've been using std::istream and ostream as a polymorphic interface for random-access binary I/O in C++, but it seems suboptimal in numerous ways: 64-bit seeks are non-portable and error-prone due to streampos/streamoff limitations; currently using boost/iostreams/positioning.hpp as a workaround, but it requires vigilance Missing operations such as truncating or extending a file (ala POSIX ftruncate) Inconsistency between concrete implementations; e.g. stringstream has independent get/put positions whereas filestream does not Inconsistency between platform implementations; e.g. behavior of seeking pass the end of a file or usage of failbit/badbit on errors Don't need all the formatting facilities of stream or possibly even the buffering of streambuf streambuf error reporting (i.e. exceptions vs. returning an error indicator) is supposedly implementation-dependent in practice I like the simplified interface provided by the Boost.Iostreams Device concept, but it's provided as function templates rather than a polymorphic class. (There is a device class, but it's not polymorphic and is just an implementation helper class not necessarily used by the supplied device implementations.) I'm primarily using large disk files, but I really want polymorphism so I can easily substitute alternate implementations (e.g. use stringstream instead of fstream for unit tests) without all the complexity and compile-time coupling of deep template instantiation. Does anyone have any recommendations of a standard approach to this? It seems like a common situation, so I don't want to invent my own interfaces unnecessarily. As an example, something like java.nio.FileChannel seems ideal. My best solution so far is to put a thin polymorphic layer on top of Boost.Iostreams devices. For example: class my_istream { public: virtual std::streampos seek(stream_offset off, std::ios_base::seekdir way) = 0; virtual std::streamsize read(char* s, std::streamsize n) = 0; virtual void close() = 0; }; template <class T> class boost_istream : public my_istream { public: boost_istream(const T& device) : m_device(device) { } virtual std::streampos seek(stream_offset off, std::ios_base::seekdir way) { return boost::iostreams::seek(m_device, off, way); } virtual std::streamsize read(char* s, std::streamsize n) { return boost::iostreams::read(m_device, s, n); } virtual void close() { boost::iostreams::close(m_device); } private: T m_device; };

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• Hibernate updating records and implementing listeners : getting only required attribute values for event.getOldState()

  - by Narendra

  Hi All, I am using Hibernate 3 as my persistence framework. Below is the sample hbm file I am using. <?xml version="1.0"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping> <class name="com.test.User" table="user"> <meta attribute="implements">com.test.dao.interfaces.IEntity</meta> <id name="key" type="long" column="user_key"> <generator class="increment" /> </id> <property name="userName" column="user_name" not-null="true" type="string" /> <property name="password" column="password" not-null="true" type="string" /> <property name="firstName" column="first_name" not-null="true" type="string" /> <property name="lastName" column="last_name" not-null="true" type="string" /> <property name="createdDate" column="created_date" not-null="true" type="timestamp" insert="false" update="false" /> <property name="createdBy" column="created_by" not-null="true" type="string" update="false" /> </class> </hibernate-mapping> I am added a post-update listener. What it will do is if there any updations perfomed on User then it will be invoked and cahnges will be inserted to audit table. Below is the sample implementation for postupdate event. public void onPostUpdate(PostUpdateEvent event) { LogHelper.info(logger, "Begin - onPostUpdate " + event.getEntity().getClass().getSimpleName()); if (!this.checkForAudit(event.getEntity().getClass().getSimpleName())) { // check do we need to audit it. } // Get Attribute Names String[] attrNames = event.getPersister().getEntityMetamodel() .getPropertyNames(); Object[] oldobjectValue = c Object[] newObjectValue = event.getState(); this.auditDetailsEvent(attrNames, oldobjectValue, newObjectValue); LogHelper.info(logger, "End - onPostUpdate"); // return false; } Here is my requirement. event.getPersister().getEntityMetamodel() .getPropertyNames(); or event.getOldState(); or event.getState(); must return attribute names or value which i can update or insert. Is there any way to control the return values of above one's. Pleas help me on this regard. Thanks, Narendra

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• Using pointers, references, handles to generic datatypes, as generic and flexible as possible

  - by Patrick

  In my application I have lots of different data types, e.g. Car, Bicycle, Person, ... (they're actually other data types, but this is just for the example). Since I also have quite some 'generic' code in my application, and the application was originally written in C, pointers to Car, Bicycle, Person, ... are often passed as void-pointers to these generic modules, together with an identification of the type, like this: Car myCar; ShowNiceDialog ((void *)&myCar, DATATYPE_CAR); The 'ShowNiceDialog' method now uses meta-information (functions that map DATATYPE_CAR to interfaces to get the actual data out of Car) to get information of the car, based on the given data type. That way, the generic logic only has to be written once, and not every time again for every new data type. Of course, in C++ you could make this much easier by using a common root class, like this class RootClass { public: string getName() const = 0; }; class Car : public RootClass { ... }; void ShowNiceDialog (RootClass *root); The problem is that in some cases, we don't want to store the data type in a class, but in a totally different format to save memory. In some cases we have hundreds of millions of instances that we need to manage in the application, and we don't want to make a full class for every instance. Suppose we have a data type with 2 characteristics: A quantity (double, 8 bytes) A boolean (1 byte) Although we only need 9 bytes to store this information, putting it in a class means that we need at least 16 bytes (because of the padding), and with the v-pointer we possibly even need 24 bytes. For hundreds of millions of instances, every byte counts (I have a 64-bit variant of the application and in some cases it needs 6 GB of memory). The void-pointer approach has the advantage that we can almost encode anything in a void-pointer and decide how to use it if we want information from it (use it as a real pointer, as an index, ...), but at the cost of type-safety. Templated solutions don't help since the generic logic forms quite a big part of the application, and we don't want to templatize all this. Additionally, the data model can be extended at run time, which also means that templates won't help. Are there better (and type-safer) ways to handle this than a void-pointer? Any references to frameworks, whitepapers, research material regarding this?

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• WndProc(ref Message m), Prevent minimize Games, Send key strokes.

  - by Stanomatic

  Overview: I am going to create a touch application that interfaces with games and other apps. This concept is similar to the app found on touch-buddy.com but I will be using C# and WPF instead of how the application is written in Perl. I have a few challenges I would like to evaluate. The touch-buddy app uses two approaches while interacting with games; 1. Client mode (Same machine runs both game and touch-buddy). 2. Server / Client mode where a separate box sends commands to the game machine. The reason I believe for this method was to circumvent the issue with games minimizing. In Client only mode I am faced with the issue where I touch a screen OTHER than the main screen where the game is viewed and then the game minimizes. Not all games have this behavior but I would like to conquer the games that do minimize and prevent it. Is it possible to keep a game front and center Focused and prevent minimizing utilizing C# WndProc(ref Message m)? I have been experimenting with WndProc(ref Message m) where I created a win form and when I press minimize on my own Win form and it will close an instance of notepad. This proves to me that I can capture a message, prevent that message from bubbling up and then send a message to another application. I then tried to click on notepad with my touch screen and keep my win form application in focus and not minimize. At this point I am unsuccessful. I need more time understanding message codes. Is this the right approach? Can it be done? Should I look at other libraries such as Windows Automation? Key input is my other concern. What is the best way to send key strokes to other apps/games. Should I tap into DirectX, use some kind of send key, Automation Framework? Can any of these handle the multiple key strokes that some simulation games require? I appreciate any links and or insight you may have. If you have gone down this path for any reason I would love to hear your comments. Stan

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• Rewriting Live TCP/IP (Layer 4) (i.e. Socket Layer) Streams

  - by user213060

  I have a simple problem which I'm sure someone here has done before... I want to rewrite Layer 4 TCP/IP streams (Not lower layer individual packets or frames.) Ettercap's etterfilter command lets you perform simple live replacements of Layer 4 TCP/IP streams based on fixed strings or regexes. Example ettercap scripting code: if (ip.proto == TCP && tcp.dst == 80) { if (search(DATA.data, "gzip")) { replace("gzip", " "); msg("whited out gzip\n"); } } if (ip.proto == TCP && tcp.dst == 80) { if (search(DATA.data, "deflate")) { replace("deflate", " "); msg("whited out deflate\n"); } } http://ettercap.sourceforge.net/forum/viewtopic.php?t=2833 I would like to rewrite streams based on my own filter program instead of just simple string replacements. Anyone have an idea of how to do this? Is there anything other than Ettercap that can do live replacement like this, maybe as a plugin to a VPN software or something? I would like to have a configuration similar to ettercap's silent bridged sniffing configuration between two Ethernet interfaces. This way I can silently filter traffic coming from either direction with no NATing problems. Note that my filter is an application that acts as a pipe filter, similar to the design of unix command-line filters: >[eth0] <----------> [my filter] <----------> [eth1]< What I am already aware of, but are not suitable: Tun/Tap - Works at the lower packet layer, I need to work with the higher layer streams. Ettercap - I can't find any way to do replacements other than the restricted capabilities in the example above. Hooking into some VPN software? - I just can't figure out which or exactly how. libnetfilter_queue - Works with lower layer packets, not TCP/IP streams. Again, the rewriting should occur at the transport layer (Layer 4) as it does in this example, instead of a lower layer packet-based approach. Exact code will help immensely! Thanks!

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• Solving a cyclical dependency in Ninject (Compact Framework)

  - by Alex

  I'm trying to use Ninject for dependency injection in my MVP application. However, I have a problem because I have two types that depend on each other, thus creating a cyclic dependency. At first, I understand that it was a problem, because I had both types require each other in their constructors. Therefore, I moved one of the dependencies to a property injection instead, but I'm still getting the error message. What am I doing wrong? This is the presenter: public class LoginPresenter : Presenter<ILoginView>, ILoginPresenter { public LoginPresenter( ILoginView view ) : base( view ) { } } and this is the view: public partial class LoginForm : Form, ILoginView { [Inject] public ILoginPresenter Presenter { private get; set; } public LoginForm() { InitializeComponent(); } } And here's the code that causes the exception: static class Program { /// <summary> /// The main entry point for the application. /// </summary> [MTAThread] static void Main() { // Show the login form Views.LoginForm loginForm = Kernel.Get<Views.Interfaces.ILoginView>() as Views.LoginForm; Application.Run( loginForm ); } } The exception happens on the line with the Kernel.Get<>() call. Here it is: Error activating ILoginPresenter using binding from ILoginPresenter to LoginPresenter A cyclical dependency was detected between the constructors of two services. Activation path: 4) Injection of dependency ILoginPresenter into property Presenter of type LoginForm 3) Injection of dependency ILoginView into parameter view of constructor of type LoginPresenter 2) Injection of dependency ILoginPresenter into property Presenter of type LoginForm 1) Request for ILoginView Suggestions: 1) Ensure that you have not declared a dependency for ILoginPresenter on any implementations of the service. 2) Consider combining the services into a single one to remove the cycle. 3) Use property injection instead of constructor injection, and implement IInitializable if you need initialization logic to be run after property values have been injected. Why doesn't Ninject understand that since one is constructor injection and the other is property injection, this can work just fine? I even read somewhere looking for the solution to this problem that Ninject supposedly gets this right as long as the cyclic dependency isn't both in the constructors. Apparently not, though. Any help resolving this would be much appreciated.

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• C++ snippet support in visual studio?

  - by Jeremy Bell

  I'm writing code in native C++ (not C++/CLR). I know that there is no built-in support for C++ with regards to the snippet manager and snipper picker interfaces, however I found a utility called "snippy" which supposedly can generate C++ snippets. Here is a c++ snippet that the program generated: <?xml version="1.0" encoding="utf-8"?> <CodeSnippets xmlns="http://schemas.microsoft.com/VisualStudio/2005/CodeSnippet"> <CodeSnippet Format="1.0.0"> <Header> <Title>MySnippet</Title> <Shortcut>MySnippet</Shortcut> <Description>Just a test snippet</Description> <Author>Me</Author> <SnippetTypes> <SnippetType>Expansion</SnippetType> </SnippetTypes> </Header> <Snippet> <Declarations> <Literal Editable="true"> <ID>literal1</ID> <ToolTip>just a placeholder</ToolTip> <Default> </Default> <Function> </Function> </Literal> </Declarations> <Code Language="cpp"><![CDATA[cout << "$literal1$" << std::endl;]]></Code> </Snippet> </CodeSnippet> </CodeSnippets> If there is support in visual C++, even in a limited capacity, for C++ snippets, how do I add them to my environment, and what are the limitations? All I need is support for basic expansion snippets that I can invoke by typing a shortcut and hitting tab, and which supports basic literals that I can tab through (basically, if it supports the above snippet, I'm good). If this can't be done, are there any free add-ons or extensions to visual studio that support snippets for C++? I'm using both visual studio 2010 and 2008, but I mostly write code in 2010 right now.

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• PHP running as a FastCGI application (php-cgi) - how to issue concurrent requests?

  - by Sbm007

  Some background information: I'm writing my own webserver in Java and a couple of days ago I asked on SO how exactly Apache interfaces with PHP, so I can implement PHP support. I learnt that FastCGI is the best approach (since mod_php is not an option). So I have looked at the FastCGI protocol specification and have managed to write a working FastCGI wrapper for my server. I have tested phpinfo() and it works, in fact all PHP functions seem to work just fine (posting data, sessions, date/time, etc etc). My webserver is able to serve requests concurrently (ie user1 can retrieve file1.html at the same time as user2 requesting some_large_binary_file.zip), it does this by spawning a new Java thread for each user request (terminating when completed or user connection with client is cancelled). However, it cannot deal with 2 (or more) FastCGI requests at the same time. What it does is, it queues them up, so when request 1 is completed immediately thereafter it starts processing request 2. I tested this with 2 PHP pages, one contains sleep(10) and the other phpinfo(). How would I go about dealing with multiple requests as I know it can be done (PHP under IIS runs as FastCGI and it can deal with multiple requests just fine). Some more info: I am coding under windows and my batch file used to execute php-cgi.exe contains: set PHP_FCGI_CHILDREN=8 set PHP_FCGI_MAX_REQUESTS=500 php-cgi.exe -b 9000 But it does not spawn 8 children, the service simply terminates after 500 requests. I have done research and from Wikipedia: Processing of multiple requests simultaneously is achieved either by using a single connection with internal multiplexing (ie. multiple requests over a single connection) and/or by using multiple connections Now clearly the multiple connections isn't working for me, as everytime a client requests something that involves FastCGI it creates a new socket to the FastCGI application, but it does not work concurrently (it queues them up instead). I know that internal multiplexing of FastCGI requests under the same connection is accomplished by issuing each unique FastCGI request with a different request ID. (also see the last 3 paragraphs of 'The Communication Protocol' heading in this article). I have not tested this, but how would I go about implementing that? I take it I need some kind of FastCGI Java thread which contains a Map of some sort and a static function which I can use to add requests to. Then in the Thread's run() function it would have a while loop and for every cycle it would check whether the Map contains new requests, if so it would assign them a request ID and write them to the FastCGI stream. And then wait for input etc etc, As you can see this becomes too complicated. Does anyone know the correct way of doing this? Or any thoughts at all? Thanks very much. Note, if required I can supply the code for my FastCGI wrapper.

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• Unable to read data from the transport connection: the connection was closed

  - by webdreamer

  The exception is Remoting Exception - Authentication Failure. The detailed message says "Unable to read data from the transport connection: the connection was closed." I'm having trouble with creating two simple servers that can comunicate as remote objects in C#. ServerInfo is just a class I created that holds the IP and Port and can give back the address. It works fine, as I used it before, and I've debugged it. Also the server is starting just fine, no exception is thrown, and the channel is registered without problems. I'm using Forms to do the interfaces, and call some of the methods on the server, but didn't find any problems in passing the parameters from the FormsApplication to the server when debugging. All seems fine in that chapter. public ChordServerProgram() { RemotingServices.Marshal(this, "PADIBook"); nodeInt = 0; } public void startServer() { try { serverChannel = new TcpChannel(serverInfo.Port); ChannelServices.RegisterChannel(serverChannel, true); } catch (Exception e) { Console.WriteLine(e.ToString()); } } I run two instances of this program. Then startNode is called on one of the instances of the application. The port is fine, the address generated is fine as well. As you can see, I'm using the IP for localhost, since this server is just for testing purposes. public void startNode(String portStr) { IPAddress address = IPAddress.Parse("127.0.0.1"); Int32 port = Int32.Parse(portStr); serverInfo = new ServerInfo(address, port); startServer(); //node = new ChordNode(serverInfo,this); } Then, in the other istance, through the interface again, I call another startNode method, giving it a seed server to get information from. This is where it goes wrong. When it calls the method on the seedServer proxy it just got, a RemotingException is thrown, due to an authentication failure. (The parameter I'll want to get is the node, I'm just using the int to make sure the ChordNode class has nothing to do with this error.) public void startNode(String portStr, String seedStr) { IPAddress address = IPAddress.Parse("127.0.0.1"); Int32 port = Int32.Parse(portStr); serverInfo = new ServerInfo(address, port); IPAddress addressSeed = IPAddress.Parse("127.0.0.1"); Int32 portSeed = Int32.Parse(seedStr); ServerInfo seedInfo = new ServerInfo(addressSeed, portSeed); startServer(); ChordServerProgram seedServer = (ChordServerProgram)Activator.GetObject(typeof(ChordServerProgram), seedInfo.GetFullAddress()); // node = new ChordNode(serverInfo,this); int seedNode = seedServer.nodeInt; // node.chordJoin(seedNode.self); }

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• Is it Bad Practice to use C++ only for the STL containers?

  - by gmatt

  First a little background ... In what follows, I use C,C++ and Java for coding (general) algorithms, not gui's and fancy program's with interfaces, but simple command line algorithms and libraries. I started out learning about programming in Java. I got pretty good with Java and I learned to use the Java containers a lot as they tend to reduce complexity of book keeping while guaranteeing great performance. I intermittently used C++, but I was definitely not as good with it as with Java and it felt cumbersome. I did not know C++ enough to work in it without having to look up every single function and so I quickly reverted back to sticking to Java as much as possible. I then made a sudden transition into cracking and hacking in assembly language, because I felt I was concentrated too much attention on a much too high level language and I needed more experience with how a CPU interacts with memory and whats really going on with the 1's and 0's. I have to admit this was one of the most educational and fun experiences I've had with computers to date. For obviously reasons, I could not use assembly language to code on a daily basis, it was mostly reserved for fun diversions. After learning more about the computer through this experience I then realized that C++ is so much closer to the "level of 1's and 0's" than Java was, but I still felt it to be incredibly obtuse, like a swiss army knife with far too many gizmos to do any one task with elegance. I decided to give plain vanilla C a try, and I quickly fell in love. It was a happy medium between simplicity and enough "micromanagent" to not abstract what is really going on. However, I did miss one thing about Java: the containers. In particular, a simple container (like the stl vector) that expands dynamically in size is incredibly useful, but quite a pain to have to implement in C every time. Hence my code currently looks like almost entirely C with containers from C++ thrown in, the only feature I use from C++. I'd like to know if its consider okay in practice to use just one feature of C++, and ignore the rest in favor of C type code?

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• Replace Components.classesByID with document.implementation.createDocument

  - by Earl Smith

  I am not the author of this code, but it is no longer maintained. So I am trying to fix it, but I have very little experience in javascript. Since Firefox 9, Components.classesByID["{3a9cd622-264d-11d4-ba06-0060b0fc76dd}"]. has been obsolete. Instead, it is suggested that document.implementation.createDocument be used. Can someone here show me how to implement these changes? I seem to be, just banging my head with everything I have tried. The example given at Mozilla developer network is: var doc = document.implementation.createDocument ("http://www.w3.org/1999/xhtml", "html", null); var body = document.createElementNS("http://www.w3.org/1999/xhtml", "body"); body.setAttribute("id", "abc"); doc.documentElement.appendChild(body); alert(doc.getElementById("abc")); // [object HTMLBodyElement] and the code in the .jsm I am trying to fix is: this.fgImageData = {}; this.fgImageData["check"] = [ " *", " **", "* ***", "** *** ", "***** ", " *** ", " * "]; this.fgImageData["radio"] = [ " **** ", "******", "******", "******", "******", " **** "]; this.fgImageData["menu-ltr"] = [ "* ", "** ", "*** ", "****", "*** ", "** ", "* "]; this.fgImageData["menu-rtl"] = [ " *", " **", " ***", "****", " ***", " **", " *"]; // I think I'm doing something slightly wrong when creating the document // but I'm not sure. It works though. *FIX* var domi = Components.classesByID["{3a9cd622-264d-11d4-ba06-0060b0fc76dd}"]. createInstance(Components.interfaces.nsIDOMDOMImplementation); this.document = domi.createDocument("http://www.w3.org/1999/xhtml", "html", null); this.canvas = this.document.createElementNS("http://www.w3.org/1999/xhtml", "html:canvas"); for(var name in this.fgImageData) { if (this.fgImageData.hasOwnProperty(name)) { var data = this.fgImageData[name]; var width = data[0].length; var height = data.length; this.canvas.width = width; this.canvas.height = height; var g = this.canvas.getContext("2d"); g.clearRect(0, 0, width, height); var idata = g.getImageData(0, 0, width, height); for(var y=0, oy=0; y<height; y++, oy+=idata.width*4) for(var x=0, ox=oy; x<width; x++, ox+=4) idata.data[ox+3] = data[y][x] == " " ? 0 : 255; this.fgImageData[name] = idata; } } },

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• Hibernate @Transactional not starting transaction

  - by rhinds

  I have a web app using Hibernate, and I am attempting to persist some data, but it is failing to persist within a Transaction despite using the @Transactional annotation. My service class is as follows: @Service("profileService") public class ProfileService { private EntityManager entityManager; @Autowired private AccountService accountService; @Autowired private ProfileDAOImpl profileDao; @PersistenceContext public void setEntityManager(EntityManager em) { this.entityManager = em; } @Transactional public void addConnectionToAccount(SocialConnection sc) { entityManager.persist(sc); } } The addConnectionToAccount() method is being called from another Spring bean in a normal method, and the ProfileService class is currently being injected there: public class HibernateConnectionRepository implements ConnectionRepository { @Inject private ProfileService profileService; @Override @Transactional public void addConnection(SocialConnection sc) { try { profileService.addConnectionToAccount(accountId, sc); } catch (Exception e) { e.printStackTrace(); } } I tried putting the @Transactional annotation on the calling method in the vain hope that it might make a difference but nothing. Previously I have experienced problems like this its been because the object being persisted does not satisfy table restrictions (such as non-nullable columns as null) or because the method is being called from within the same class and the calling method is not Transactional, but neither of those are the case here.. Any ideas? it just fails silently, the logs are as follows: 2012-03-26 22:25:04,702 [http-bio-8085-exec-9] DEBUG com.mchange.v2.resourcepool.BasicResourcePool - trace com.mchange.v2.resourcepool.BasicResourcePool@1bc25c8 [managed: 3, unused: 2, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@e5b006) 2012-03-26 22:25:04,710 [http-bio-8085-exec-9] DEBUG org.hibernate.SQL - select SEQ_COUNT from SEQUENCE where SEQ_NAME = 'PO_SEQ' for update 2012-03-26 22:25:04,711 [http-bio-8085-exec-9] DEBUG org.hibernate.SQL - update SEQUENCE set SEQ_COUNT = ? where SEQ_COUNT = ? and SEQ_NAME = 'PO_SEQ' 2012-03-26 22:25:04,723 [http-bio-8085-exec-9] DEBUG com.mchange.v2.resourcepool.BasicResourcePool - trace com.mchange.v2.resourcepool.BasicResourcePool@1bc25c8 [managed: 3, unused: 2, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@e5b006) 2012-03-26 22:25:04,723 [http-bio-8085-exec-9] DEBUG org.hibernate.event.internal.AbstractSaveEventListener - Generated identifier: 2200, using strategy: org.hibernate.id.MultipleHiLoPerTableGenerator UPDATE Also wanted to mention that the HibernateConnectionRepository bean is not annotated and is actually being configured in an @Configuration class (if this makes any difference? not used @Configuration classes much). The method to create the bean is as follows: @Bean @Scope(value = "request", proxyMode = ScopedProxyMode.INTERFACES) public ConnectionRepository connectionRepository() { Authentication authentication = SecurityContextHolder.getContext().getAuthentication(); if (authentication == null) { throw new IllegalStateException("Unable to get a ConnectionRepository: no user signed in"); } ApplicationUser user = (ApplicationUser) authentication.getPrincipal(); return usersConnectionRepository().createConnectionRepository(String.valueOf(user.getAccountId())); } The bean is scoped to the logged in user, but may also be created multiple times for each user..

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• How to distort the desktop screen

  - by HaifengWang

  Hi friends, I want to change the shape of the desktop screen, so what are displayed on the desktop will be distorted at the same time. And the user can still operate the PC with the mouse on the distorted desktop(Run the applications, Open the "My Computer" and so on). I think I must get the projection matrix of the screen coordinate at first. Then transform the matrix, and map the desktop buffer image to the distorted mesh. Are there any interfaces which can modify the shape of the desktop screen in OpenGL or DirectX? Would you please give me some tip on it. Thank you very much in advance. Please refer to the picture from http://oi53.tinypic.com/bhewdx.jpg BR, Haifeng Addition1: I'm sorry! Maybe I didn't express clearly what I want to implement. What I want to implement is to modify the shape of the screen. So we can distort the shapes of all the applications which are run on Windows at the same time. For example that the window of "My Computer" will be distorted with the distortion of the desktop screen. And we can still operate the PC with mouse from the distorted desktop(Click the shortcut to run a program). Addition2: The projection matrix is just my assume. There isn't any desktop projection matrix by which the desktop surface is projected to the screen. What I want to implement is to change the shape of the desktop, as the same with mapping the desktop to an 3D mesh. But the user can still operate the OS on the distorted desktop(Click the shortcut to run a program, open the ie to surf the internet). Addition3: The shapes of all the programs run on the OS are changed with the distortion of the screen. It's realtime. The user can still operate the OS on the distorted screen as usually. Maybe we can intercept or override the GPU itself to implement the effect. I'm investigating GDI, I think I can find some clue for that. The first step is to find how to show the desktop on the screen.

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• Marshalling non-Blittable Structs from C# to C++

  - by Greggo

  I'm in the process of rewriting an overengineered and unmaintainable chunk of my company's library code that interfaces between C# and C++. I've started looking into P/Invoke, but it seems like there's not much in the way of accessible help. We're passing a struct that contains various parameters and settings down to unmanaged codes, so we're defining identical structs. We don't need to change any of those parameters on the C++ side, but we do need to access them after the P/Invoked function has returned. My questions are: What is the best way to pass strings? Some are short (device id's which can be set by us), and some are file paths (which may contain Asian characters) Should I pass an IntPtr to the C# struct or should I just let the Marshaller take care of it by putting the struct type in the function signature? Should I be worried about any non-pointer datatypes like bools or enums (in other, related structs)? We have the treat warnings as errors flag set in C++ so we can't use the Microsoft extension for enums to force a datatype. Is P/Invoke actually the way to go? There was some Microsoft documentation about Implicit P/Invoke that said it was more type-safe and performant. For reference, here is one of the pairs of structs I've written so far: C++ /** Struct used for marshalling Scan parameters from managed to unmanaged code. */ struct ScanParameters { LPSTR deviceID; LPSTR spdClock; LPSTR spdStartTrigger; double spinRpm; double startRadius; double endRadius; double trackSpacing; UINT64 numTracks; UINT32 nominalSampleCount; double gainLimit; double sampleRate; double scanHeight; LPWSTR qmoPath; //includes filename LPWSTR qzpPath; //includes filename }; C# /// <summary> /// Struct used for marshalling scan parameters between managed and unmanaged code. /// </summary> [StructLayout(LayoutKind.Sequential)] public struct ScanParameters { [MarshalAs(UnmanagedType.LPStr)] public string deviceID; [MarshalAs(UnmanagedType.LPStr)] public string spdClock; [MarshalAs(UnmanagedType.LPStr)] public string spdStartTrigger; public Double spinRpm; public Double startRadius; public Double endRadius; public Double trackSpacing; public UInt64 numTracks; public UInt32 nominalSampleCount; public Double gainLimit; public Double sampleRate; public Double scanHeight; [MarshalAs(UnmanagedType.LPWStr)] public string qmoPath; [MarshalAs(UnmanagedType.LPWStr)] public string qzpPath; }

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• Passing ViewModel for backbone.js from MVC3 Server-Side

  - by Roman

  In ASP.NET MVC there is Model, View and Controller. MODEL represents entities which are stored in database and essentially is all the data used in a application (for example, generated by EntityFramework, "DB First" approach). Not all data from model you want to show in the view (for example, hashs of passwords). So you create VIEW MODEL, each for every strongly-typed-razor-view you have in application. Like this: using System; using System.Collections.Generic; using System.Linq; using System.Web; namespace MyProject.ViewModels.SomeController.SomeAction { public class ViewModel { public ViewModel() { Entities1 = new List<ViewEntity1>(); Entities2 = new List<ViewEntity2>(); } public List<ViewEntity1> Entities1 { get; set; } public List<ViewEntity2> Entities2 { get; set; } } public class ViewEntity1 { //some properties from original DB-entity you want to show } public class ViewEntity2 { } } When you create complex client-side interfaces (I do), you use some pattern for javascript on client, MVC or MVVM (I know only these). So, with MVC on client you have another model (Backbone.Model for example), which is third model in application. It is a bit much. Why don`t we use the same ViewModel model on a client (in backbone.js or another framework)? Is there a way to transfer CS-coded model to JS-coded? Like in MVVM pattern, with knockout.js, when you can do like this: in SomeAction.cshtml: <div style="display: none;" id="view_model">@Json.Encode(Model)</div> after that in Javascript-code var ViewModel = ko.mapping.fromJSON($("#view_model").get(0).innerHTML); now you can extend your ViewModel with some actions, event handlers, etc: ko.utils.extend(ViewModel, { some_function: function () { //some code } }); So, we are not building the same view model on the client again, we are transferring existing view model from server. At least, data. But knockout.js is not suitable for me, you can`t build complex UI with it, it is just data-binding. I need something more structural, like backbone.js. The only way to build ViewModel for backbone.js I can see now is re-writing same ViewModel in JS from server with hands. Is there any ways to transfer it from server? To reuse the same viewmodel on server view and client view?

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• Java: Making concurrent MySQL queries from multiple clients synchronised

  - by Misha Gale

  I work at a gaming cybercafe, and we've got a system here (smartlaunch) which keeps track of game licenses. I've written a program which interfaces with this system (actually, with it's backend MySQL database). The program is meant to be run on a client PC and (1) query the database to select an unused license from the pool available, then (2) mark this license as in use by the client PC. The problem is, I've got a concurrency bug. The program is meant to be launched simultaneously on multiple machines, and when this happens, some machines often try and acquire the same license. I think that this is because steps (1) and (2) are not synchronised, i.e. one program determines that license #5 is available and selects it, but before it can mark #5 as in use another copy of the program on another PC tries to grab that same license. I've tried to solve this problem by using transactions and table locking, but it doesn't seem to make any difference - Am I doing this right? Here follows the code in question: public LicenseKey Acquire() throws SmartLaunchException, SQLException { Connection conn = SmartLaunchDB.getConnection(); int PCID = SmartLaunchDB.getCurrentPCID(); conn.createStatement().execute("LOCK TABLE `licensekeys` WRITE"); String sql = "SELECT * FROM `licensekeys` WHERE `InUseByPC` = 0 AND LicenseSetupID = ? ORDER BY `ID` DESC LIMIT 1"; PreparedStatement statement = conn.prepareStatement(sql); statement.setInt(1, this.id); ResultSet results = statement.executeQuery(); if (results.next()) { int licenseID = results.getInt("ID"); sql = "UPDATE `licensekeys` SET `InUseByPC` = ? WHERE `ID` = ?"; statement = conn.prepareStatement(sql); statement.setInt(1, PCID); statement.setInt(2, licenseID); statement.executeUpdate(); statement.close(); conn.commit(); conn.createStatement().execute("UNLOCK TABLES"); return new LicenseKey(results.getInt("ID"), this, results.getString("LicenseKey"), results.getInt("LicenseKeyType")); } else { throw new SmartLaunchException("All licenses of type " + this.name + "are in use"); } }

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• Is a Multi-DAL Approach the way to go here?

  - by Krisc

  Working on the data access / model layer in this little MVC2 project and trying to think things out to future projects. I have a database with some basic tables and I have classes in the model layer that represent them. I obviously need something to connect the two. The easiest is to provide some sort of 'provider' that can run operations on the database and return objects. But this is for a website that would potentially be used "a lot" (I know, very general) so I want to cache results from the data layer and keep the cache updated as new data is generated. This question deals with how best to approach this problem of dual DALS. One that returns cached data when possible and goes to the data layer when there is a cache miss. But more importantly, how to integrate the core provider (thing that goes into database) with the caching layer so that it too can rely on cached objects rather than creating new ones. Right now I have the following interfaces: IDataProvider is used to reach the database. It doesn't concern itself with the meaning of the objects it produces, but simply the way to produce them. interface IDataProvider{ // Select, Update, Create, et cetera access IEnumerable<Entry> GetEntries(); Entry GetEntryById(int id); } IDataManager is a layer that sits on top of the IDataProvider layer and manages the cache interface IDataManager : IDataProvider{ void ClearCache(); } Note that in practice the IDataManager implementation will have useful helper functions to add objects to their related cache stores. (In the future I may define other functions on the interface) I guess what I am looking for is the best way to approach a loop back from the IDataProvider implementations so that they can access the cache. Or a different approach entirely may be in order? I am not very interested in 3rd party products at the moment as I am interested in the design of these things much more than this specific implementation. Edit: I realize the title may be a bit misleading. I apologize for that... not sure what to call this question.

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• Getting up to speed on modern architecture

  - by Matt Thrower

  Hi, I don't have any formal qualifications in computer science, rather I taught myself classic ASP back in the days of the dotcom boom and managed to get myself a job and my career developed from there. I was a confident and, I think, pretty good programmer in ASP 3 but as others have observed one of the problems with classic ASP was that it did a very good job of hiding the nitty-gritty of http so you could become quite competent as a programmer on the basis of relatively poor understanding of the technology you were working with. When I changed on to .NET at first I treated it like classic ASP, developing stand-alone applications as individual websites simply because I didn't know any better at the time. I moved jobs at this point and spent the next several years working on a single site whose architecture relied heavily on custom objects: in other words I gained a lot of experience working with .NET as a middle-tier development tool using a quite old-fashioned approach to OO design along the lines of the classic "car" class example that's so often used to teach OO. Breaking down programs into blocks of functionality and basing your classes and methods around that. Although we worked under an Agile approach to manage the work the whole setup was classic client/server stuff. That suited me and I gradually got to grips with .NET and started using it far more in the manner that it should be, and I began to see the power inherent in the technology and precisely why it was so much better than good old ASP 3. In my latest job I have found myself suddenly dropped in at the deep end with two quite young, skilled and very cutting-edge programmers. They've built a site architecture which is modelling along a lot of stuff which is new to me and which, in truth I'm having a lot of trouble understanding. The application is built on a cloud computing model with multi-tenancy and the architecture is all loosely coupled using a lot of interfaces, factories and the like. They use nHibernate a lot too. Shortly after I joined, both these guys left and I'm now supposedly the senior developer on a system whose technology and architecture I don't really understand and I have no-one to ask questions of. Except you, the internet. Frankly I feel like I've been pitched in at the deep end and I'm sinking. I'm not sure if this is because I lack the educational background to understand this stuff, if I'm simply not mathematically minded enough for modern computing (my maths was never great - my approach to design is often to simply debug until it works, then refactor until it looks neat), or whether I've simply been presented with too much of too radical a nature at once. But the only way to find out which it is is to try and learn it. So can anyone suggest some good places to start? Good books, tutorials or blogs? I've found a lot of internet material simply presupposes a level of understanding that I just don't have. Your advice is much appreciated. Help a middle-aged, stuck in the mud developer get enthusastic again! Please!

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• Subclassing and adding data members

  - by Marius

  I have an hierarchy of classes that looks like the following: class Critical { public: Critical(int a, int b) : m_a(a), m_b(b) { } virtual ~Critical() { } int GetA() { return m_a; } int GetB() { return m_b; } void SetA(int a) { m_a = a; } void SetB(int b) { m_b = b; } protected: int m_a; int m_b; }; class CriticalFlavor : public Critical { public: CriticalFlavor(int a, int b, int flavor) : Critical(a, b), m_flavor(flavor) { } virtual ~CriticalFlavor() { } int GetFlavor() { return m_flavor; } void SetFlavor(int flavor) { m_flavor = flavor; } protected: int m_flavor; }; class CriticalTwist : public Critical { public: CriticalTwist(int a, int b, int twist) : Critical(a, b), m_twist(twist) { } virtual ~CriticalTwist() { } int GetTwist() { return m_twist; } void SetTwist(int twist) { m_twist = twist; } protected: int m_twist; }; The above does not seem right to me in terms of the design and what bothers me the most is the fact that the addition of member variables seems to drive the interface of these classes (the real code that does the above is a little more complex but still embracing the same pattern). That will proliferate when in need for another "Critical" class that just adds some other property. Does this feel right to you? How could I refactor such code? An idea would be to have just a set of interfaces and use composition when it comes to the base object like the following: class Critical { public: virtual int GetA() = 0; virtual int GetB() = 0; virtual void SetA(int a) = 0; virtual void SetB(int b) = 0; }; class CriticalImpl { public: CriticalImpl(int a, int b) : m_a(a), m_b(b) { } ~CriticalImpl() { } int GetA() { return m_a; } int GetB() { return m_b; } void SetA(int a) { m_a = a; } void SetB(int b) { m_b = b; } private: int m_a; int m_b; }; class CriticalFlavor { public: virtual int GetFlavor() = 0; virtual void SetFlavor(int flavor) = 0; }; class CriticalFlavorImpl : public Critical, public CriticalFlavor { public: CriticalFlavorImpl(int a, int b, int flavor) : m_flavor(flavor), m_critical(new CriticalImpl(a, b)) { } ~CriticalFlavorImpl() { delete m_critical; } int GetFlavor() { return m_flavor; } void SetFlavor(int flavor) { m_flavor = flavor; } int GetA() { return m_critical-GetA(); } int GetB() { return m_critical-GetB(); } void SetA(int a) { m_critical-SetA(a); } void SetB(int b) { m_critical-SetB(b); } private: int m_flavor; CriticalImpl* m_critical; };

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• Hibernate Persistence problems with Bean Mapping (Dozer)

  - by BuffaloBuffalo

  I am using Hibernate 3, and having a particular issue when persisting a new Entity which has an association with an existing detached entity. Easiest way to explain this is via code samples. I have two entities, FooEntity and BarEntity, of which a BarEntity can be associated with many FooEntity: @Entity public class FooEntity implements Foo{ @Id private Long id; @ManyToOne(targetEntity = BarEntity.class) @JoinColumn(name = "bar_id", referencedColumnName = "id") @Cascade(value={CascadeType.ALL}) private Bar bar; } @Entity public class BarEntity implements Bar{ @Id private Long id; @OneToMany(mappedBy = "bar", targetEntity = FooEntity.class) private Set<Foo> foos; } Foo and Bar are interfaces that loosely define getters for the various fields. There are corresponding FooImpl and BarImpl classes that are essentially just the entity objects without the annotations. What I am trying to do is construct a new instance of FooImpl, and persist it after setting a number of fields. The new Foo instance will have its 'bar' member set to an existing Bar (runtime being a BarEntity) from the database (retrieved via session.get(..)). After the FooImpl has all of its properties set, Apache Dozer is used to map between the 'domain' object FooImpl and the Entity FooEntity. What Dozer is doing in the background is instantiating a new FooEntity and setting all of the matching fields. BarEntity is cloned as well via instantiation and set the FooEntity's 'bar' member. After this occurs, passing the new FooEntity object to persist. This throws the exception: org.hibernate.PersistentObjectException: detached entity passed to persist: com.company.entity.BarEntity Below is in code the steps that are occurring FooImpl foo = new FooImpl(); //returns at runtime a persistent BarEntity through session.get() Bar bar = BarService.getBar(1L); foo.setBar(bar); ... //This constructs a new instance of FooEntity, with a member 'bar' which itself is a new instance that is detached) FooEntity entityToPersist = dozerMapper.map(foo, FooEntity.class); ... session.persist(entityToPersist); I have been able to resolve this issue by either removing or changing the @Cascade annotation, but that limits future use for say adding a new Foo with a new Bar attached to it already. Is there some solution here I am missing? I would be surprised if this issue hasn't been solved somewhere before, either by altering how Dozer Maps the children of Foo or how Hibernate reacts to a detached Child Entity.

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• Hot to get rid of memory allocations/deallocations in swig wrappers?

  - by Dmitriy Matveev

  I want to use swig for generation of read-only wrappers for a complex object. The object which I want to wrap will always be existent while I will read it. And also I will only use my wrappers at the time that object is existent, thus I don't need any memory management from SWIG. For following swig interface: %module test %immutable; %inline %{ struct Foo { int a; }; struct Bar { int b; Foo f; }; %} I will have a wrappers which will have a lot of garbage in generated interfaces and do useless work which will reduce performance in my case. Generated java wrapper for Bar class will be like this: public class Bar { private long swigCPtr; protected boolean swigCMemOwn; protected Bar(long cPtr, boolean cMemoryOwn) { swigCMemOwn = cMemoryOwn; swigCPtr = cPtr; } protected static long getCPtr(Bar obj) { return (obj == null) ? 0 : obj.swigCPtr; } protected void finalize() { delete(); } public synchronized void delete() { if (swigCPtr != 0) { if (swigCMemOwn) { swigCMemOwn = false; testJNI.delete_Bar(swigCPtr); } swigCPtr = 0; } } public int getB() { return testJNI.Bar_b_get(swigCPtr, this); } public Foo getF() { return new Foo(testJNI.Bar_f_get(swigCPtr, this), true); } public Bar() { this(testJNI.new_Bar(), true); } } I don't need 'swigCMemOwn' field in my wrapper since it always will be false. All code related to this field will also be useless. There are also unnecessary logic in native code: SWIGEXPORT jlong JNICALL Java_some_testJNI_Bar_1f_1get(JNIEnv *jenv, jclass jcls, jlong jarg1, jobject jarg1_) { jlong jresult = 0 ; struct Bar *arg1 = (struct Bar *) 0 ; Foo result; (void)jenv; (void)jcls; (void)jarg1_; arg1 = *(struct Bar **)&jarg1; result = ((arg1)->f); { Foo * resultptr = (Foo *) malloc(sizeof(Foo)); memmove(resultptr, &result, sizeof(Foo)); *(Foo **)&jresult = resultptr; } return jresult; } I don't need these calls to malloc and memmove. I want to force swig to resolve both of these problems, but don't know how. Is it possible?

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• Trouble with abstract generic methods

  - by DanM

  Let's say I have a class library that defines a couple entity interfaces: public interface ISomeEntity { /* ... */ } public interface ISomeOtherEntity { /* ... */ } This library also defines an IRepository interface: public interface IRepository<TEntity> { /* ... */ } And finally, the library has an abstract class called RepositorySourceBase (see below), which the main project needs to implement. The goal of this class is to allow the base class to grab new Repository objects at runtime. Because certain repositories are needed (in this example a repository for ISomeEntity and ISomeOtherEntity), I'm trying to write generic overloads of the GetNew<TEntity>() method. The following implementation doesn't compile (the second GetNew() method gets flagged as "already defined" even though the where clause is different), but it gets at what I'm trying to accomplish: public abstract class RepositorySourceBase // This doesn't work! { public abstract Repository<TEntity> GetNew<TEntity>() where TEntity : SomeEntity; public abstract Repository<TEntity> GetNew<TEntity>() where TEntity : SomeOtherEntity; } The intended usage of this class would be something like this: public class RepositorySourceTester { public RepositorySourceTester(RepositorySourceBase repositorySource) { var someRepository = repositorySource.GetNew<ISomeEntity>(); var someOtherRepository = repositorySource.GetNew<ISomeOtherEntity>(); } } Meanwhile, over in my main project (which references the library project), I have implementations of ISomeEntity and ISomeOtherEntity: public class SomeEntity : ISomeEntity { /* ... */ } public class SomeOtherEntity : ISomeOtherEntity { /* ... */ } The main project also has an implementation for IRepository<TEntity>: public class Repository<TEntity> : IRepository<TEntity> { public Repository(string message) { } } And most importantly, it has an implementation of the abstract RepositorySourceBase: public class RepositorySource : RepositorySourceBase { public override Repository<SomeEntity> GetNew() { return new Repository<SomeEntity>("stuff only I know"); } public override Repository<SomeOtherEntity> GetNew() { return new Repository<SomeOtherEntity>("other stuff only I know"); } } Just as with RepositorySourceBase, the second GetNew() method gets flagged as "already defined". So, C# basically think I'm repeating the same method because there's no way to distinguish the methods from parameters, but if you look at my usage example, it seems like I should be able to distinguish which GetNew() I want from the generic type parameter, e.g, <ISomeEntity> or <ISomeOtherEntity>. What do I need to do to get this to work?

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• C# Different class objects in one list

  - by jeah_wicer

  I have looked around some now to find a solution to this problem. I found several ways that could solve it but to be honest I didn't realize which of the ways that would be considered the "right" C# or OOP way of solving it. My goal is not only to solve the problems but also to develop a good set of code standards and I'm fairly sure there's a standard way to handle this problem. Let's say I have 2 types of printer hardwares with their respective classes and ways of communicating: PrinterType1, PrinterType2. I would also like to be able to later on add another type if neccessary. One step up in abstraction those have much in common. It should be possible to send a string to each one of them as an example. They both have variables in common and variables unique to each class. (One for instance communicates via COM-port and has such an object, while the other one communicates via TCP and has such an object). I would however like to just implement a List of all those printers and be able to go through the list and perform things as "Send(string message)" on all Printers regardless of type. I would also like to access variables like "PrinterList[0].Name" that are the same for both objects, however I would also at some places like to access data that is specific to the object itself (For instance in the settings window of the application where the COM-port name is set for one object and the IP/port number for another). So, in short something like: In common: Name Send() Specific to PrinterType1: Port Specific to PrinterType2: IP And I wish to, for instance, do Send() on all objects regardless of type and the number of objects present. I've read about polymorphism, Generics, interfaces and such, but I would like to know how this, in my eyes basic, problem typically would be dealt with in C# (and/or OOP in general). I actually did try to make a base class, but it didn't quite seem right to me. For instance I have no use of a "string Send(string Message)" function in the base class itself. So why would I define one there that needs to be overridden in the derived classes when I would never use the function in the base class ever in the first place? I'm really thankful for any answers. People around here seem very knowledgeable and this place has provided me with many solutions earlier. Now I finally have an account to answer and vote with too. EDIT: To additionally explain, I would also like to be able to access the objects of the actual printertype. For instance the Port variable in PrinterType1 which is a SerialPort object. I would like to access it like: PrinterList[0].Port.Open() and have access to the full range of functionality of the underlaying port. At the same time I would like to call generic functions that work in the same way for the different objects (but with different implementations): foreach (printer in Printers) printer.Send(message)

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• Configuring Cisco 877W router from scratch for DHCP, WiFi, ADSL2+, NAT

  - by David M Williams

  Hi all, I apologise if this is a BIG question but I am quite lost with the Cisco IOS. I know what I want to achieve just not how to do it :( I have a Cisco 877W router with 4 FastEthernet interfaces, 1 ATM interface and 1 802.11 Radio. I want to set it up for a small network and am trying to construct a configuration below. I was using Google to try and flesh it out but I think I need help and guidance from actual experts! If it helps, output from show ver says Cisco IOS software, C870 software (C870-ADVSECURITYK9-M), version 12.4(4)T7, release software (fc1) ROM: System bootstrap, version 12.3(8r)YI4, release software Here's what I have so far, which hopefully outlines clearly enough what I am wanting to do. The bits in angle brackets are placeholders (eg the secret password). ! ! Set router hostname ! hostname Shazam ! ! Set usernames and passwords ! username david privilege 15 secret 0 <PASSWORD> enable secret <SECRETPASSWORD> ! ! Configure SSH and telnet access ! line vty 0 4 privilege level 15 login local transport input telnet ssh ! ! Local logging ! logging buffered 51200 warning ! ! Set date and time for NSW, Australia (GMT +10h) ! ! ! Set router IP address to 192.168.1.1 on FastEthernet0 port ! interface FastEthernet0 ip address 192.168.1.1 255.255.255.0 no shut ip nat inside ! ! Forward any unknown DNS requests to Google ! ip dns server ip name-server 8.8.8.8 ip name-server 8.8.4.4 ! ! Set up DHCP ! DHCP pool covers 192.168.1.100 - .199 ! Set gateway and DNS server to be the router, ie 192.168.1.1 ! service dhcp ip routing ip dhcp excluded-address 192.168.1.1 192.168.1.99 ip dhcp excluded-address 192.168.1.200 192.168.1.255 ip dhcp pool <DHCPPOOLNAME> network 192.168.1.0 255.255.255.0 default-router 192.168.1.1 dns-server 192.168.1.1 lease 7 ! ! DHCP reservations ! ! Assign IP address 192.168.1.105 to MAC address 00-21-5D-2F-58-04 ! ! Configure ADSL2 connection details ! interface atm dsl operating-mode adsl2+ ! ! Set up NAT rules ! ! Forward port 35394 to 192.168.1.105 ! ! Set up WiFi ! ! SSID visible, WPA2 security, Pre-shared key I'm hoping most of this is boiler-plate stuff to you guys. I'm keen to not just get a working script but to actually understand it also. Unfortunately, I'm finding the Cisco reference material online very complex. Thank you!

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