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  • upgrading to spring 3.0 problem with interceptorNames

    - by mkoryak
    I am trying to upgrade to Spring 3.0 and i have the following issues: Finding the dependencies. People recommend using maven, but id rather not try to learn how to use maven/install it if the jars are available somewhere for download. The following bean declaration is now longer valid but i dont know how to fix it: <bean id="service" class="org.springframework.aop.framework.ProxyFactoryBean"> <property name="proxyInterfaces" value="com.service.SomeService" /> <property name="target"> <bean class="com.service.SomeServiceImpl"> </bean> </property> <property name="interceptorNames"> <list> <value>hibernateInterceptor</value> </list> </property> </bean> The complaint is that <property name="interceptorNames"> is no longer supported and should be done some other way

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  • With this generics code why am I getting "Argument 1: cannot convert from 'ToplogyLibrary.Relationsh

    - by Greg
    Hi, Any see why I'm getting a "Argument 1: cannot convert from 'ToplogyLibrary.RelationshipBase' to 'TRelationship'" in the code below, in CreateRelationship() ? public class TopologyBase<TKey, TNode, TRelationship> where TNode : NodeBase<TKey>, new() where TRelationship : RelationshipBase<TKey>, new() { // Properties public Dictionary<TKey, TNode> Nodes { get; private set; } public List<TRelationship> Relationships { get; private set; } // Constructors protected TopologyBase() { Nodes = new Dictionary<TKey, TNode>(); Relationships = new List<TRelationship>(); } // Methods public TNode CreateNode(TKey key) { var node = new TNode {Key = key}; Nodes.Add(node.Key, node); return node; } public void CreateRelationship(TNode parent, TNode child) { // Validation if (!Nodes.ContainsKey(parent.Key) || !Nodes.ContainsKey(child.Key)) { throw new ApplicationException("Can not create relationship as either parent or child was not in the graph: Parent:" + parent.Key + ", Child:" + child.Key); } // Add Relationship var r = new RelationshipBase<TNode>(); r.Parent = parent; r.Child = child; Relationships.Add(r); // *** HERE *** "Argument 1: cannot convert from 'ToplogyLibrary.RelationshipBase<TNode>' to 'TRelationship'" } } public class RelationshipBase<TNode> { public TNode Parent { get; set; } public TNode Child { get; set; } } public class NodeBase<T> { public T Key { get; set; } public NodeBase() { } public NodeBase(T key) { Key = key; } }

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  • How can I improve the performance of LinqToSql queries that use EntitySet properties?

    - by DanM
    I'm using LinqToSql to query a small, simple SQL Server CE database. I've noticed that any operations involving sub-properties are disappointingly slow. For example, if I have a Customer table that is referenced by an Order table, LinqToSql will automatically create an EntitySet<Order> property. This is a nice convenience, allowing me to do things like Customer.Order.Where(o => o.ProductName = "Stopwatch"), but for some reason, SQL Server CE hangs up pretty bad when I try to do stuff like this. One of my queries, which isn't really that complicated takes 3-4 seconds to complete. I can get the speed up to acceptable, even fast, if I just grab the two tables individually and convert them to List<Customer> and List<Order>, then join then manually with my own query, but this is throwing out a lot of what makes LinqToSql so appealing. So, I'm wondering if I can somehow get the whole database into RAM and just query that way, then occasionally save it. Is this possible? How? If not, is there anything else I can do to boost the performance besides resorting to doing all the joins manually? Note: My database in its initial state is about 250K and I don't expect it to grow to more than 1-2Mb. So, loading the data into RAM certainly wouldn't be a problem from a memory point of view. Update Here are the table definitions for the example I used in my question: create table Order ( Id int identity(1, 1) primary key, ProductName ntext null ) create table Customer ( Id int identity(1, 1) primary key, OrderId int null references Order (Id) )

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  • Optimize a MySQL count each duplicate Query

    - by Onema
    I have the following query That gets the city name, city id, the region name, and a count of duplicate names for that record: SELECT Country_CA.City AS currentCity, Country_CA.CityID, globe_region.region_name, ( SELECT count(Country_CA.City) FROM Country_CA WHERE City LIKE currentCity ) as counter FROM Country_CA LEFT JOIN globe_region ON globe_region.region_id = Country_CA.RegionID AND globe_region.country_code = Country_CA.CountryCode ORDER BY City This example is for Canada, and the cities will be displayed on a dropdown list. There are a few towns in Canada, and in other countries, that have the same names. Therefore I want to know if there is more than one town with the same name region name will be appended to the town name. Region names are found in the globe_region table. Country_CA and globe_region look similar to this (I have changed a few things for visualization purposes) CREATE TABLE IF NOT EXISTS `Country_CA` ( `City` varchar(75) NOT NULL DEFAULT '', `RegionID` varchar(10) NOT NULL DEFAULT '', `CountryCode` varchar(10) NOT NULL DEFAULT '', `CityID` int(11) NOT NULL DEFAULT '0', PRIMARY KEY (`City`,`RegionID`), KEY `CityID` (`CityID`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8; AND CREATE TABLE IF NOT EXISTS `globe_region` ( `country_code` char(2) COLLATE utf8_unicode_ci NOT NULL, `region_code` char(2) COLLATE utf8_unicode_ci NOT NULL, `region_name` varchar(50) COLLATE utf8_unicode_ci NOT NULL, PRIMARY KEY (`country_code`,`region_code`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci; The query on the top does exactly what I want it to do, but It takes way too long to generate a list for 5000 records. I would like to know if there is a way to optimize the sub-query in order to obtain the same results faster. the results should look like this City CityID region_name counter sheraton 2349269 British Columbia 1 sherbrooke 2349270 Quebec 2 sherbrooke 2349271 Nova Scotia 2 shere 2349273 British Columbia 1 sherridon 2349274 Manitoba 1

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  • Reference - What does this error mean in PHP?

    - by hakre
    On Stackoverflow you can see a lot of questions popping up about errors. Some users do not even know that error messages exists, others are asking about code that gives an error message but they do not understand the error message. If the error message is common, many questions about the same kind of error appears, but it is hard to find existing Q&A about the topic. Please add "your favorite" error message, one per answer, a short description what it means (even if it is only highlighting terms to their manual page) and a listing of existing Q&A that are of value. This will create a list. The question is a community wiki, so you are not answering for reputation but for creating a reference list for new users. It's based on error messages. Compare with the existing Reference - What does this symbol mean in PHP? question, which works pretty well. What are common errors in PHP and what are their Solutions. Index of Errors Just starting, but there are already some: Warning: Cannot modify header information - headers already sent Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in ... on line Parse error: syntax error, unexpected T_XXX in YYY on line ZZZ Fatal Error: Call to a member function ... on a non-object

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  • What is the proper way to use a Logger in a Serializable Java class?

    - by Tim Visher
    I have the following (doctored) class in a system I'm working on and Findbugs is generating a SE_BAD_FIELD warning and I'm trying to understand why it would say that before I fix it in the way that I thought I would. The reason I'm confused is because the description would seem to indicate that I had used no other non-serializable instance fields in the class but bar.model.Foo is also not serializable and used in the exact same way (as far as I can tell) but Findbugs generates no warning for it. import bar.model.Foo; import java.io.File; import java.io.Serializable; import java.util.List; import org.slf4j.Logger; import org.slf4j.LoggerFactory; public class Demo implements Serializable { private final Logger logger = LoggerFactory.getLogger(this.getClass()); private final File file; private final List<Foo> originalFoos; private Integer count; private int primitive = 0; public Demo() { for (Foo foo : originalFoos) { this.logger.debug(...); } } ... } My initial blush at a solution is to get a logger reference from the factory right as I use it: public DispositionFile() { Logger logger = LoggerFactory.getLogger(this.getClass()); for (Foo foo : originalFoos) { this.logger.debug(...); } } That doesn't seem particularly efficient, though. Thoughts?

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  • error message The URI does not identify an external Java class

    - by iHeartGreek
    Hi! I am new to XSL, and thus new to using scripts within the XSL. I have taken example code (also using C#) and adapted it for my own use.. but it does not work. The error message is: The URI urn:cs-scripts does not identify an external Java class The relevant code I have is: <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:msxsl="urn:schemas-microsoft-com:xslt" exclude-result-prefixes="msxsl" xmlns:strTok="urn:cs-scripts"> ... ... ... </xsl:template> <xsl:variable name="temp"> <xsl:value-of select="tok:getList('AAA BBB CCC', ' ')"/> </xsl:variable> <msxsl:script language="C#" implements-prefix="tok"> <![CDATA[ public string[] getList(string str, char[] delim) { return str.Split(delim, StringSplitOptions.None); } public string getString(string[] list, int i) { return list[i]; } ]]> </msxsl:script> </xsl:stylesheet>

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  • NetBeans Platform - how to refresh the property sheet view of a node?

    - by I82Much
    Hi all, I am using the PropertySheetView component to visualize and edit the properties of a node. This view should always reflect the most recent properties of the object; if there is a change to the object in another process, I want to somehow refresh the view and see the updated properties. The best way I was able to do this is something like the following (making use of EventBus library to publish and subscribe to changes in objects): public DomainObjectWrapperNode(DomainObject obj) { super (Children.LEAF, Lookups.singleton(obj)); EventBus.subscribe(DomainObject.class, this); } public void onEvent(DomainObject event) { // Do a check to determine if the updated object is the one wrapped by this node; // if so fire a property sets change firePropertySetsChange(null, this.getPropertySets()); } This works, but my place in the scrollpane is lost when the sheet refreshes; it resets the view to the top of the list and I have to scroll back down to where I was before the refresh action. So my question is, is there a better way to refresh the property sheet view of a node, specifically so my place in the property list is not lost upon refresh?

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  • Can't create new "enterprise" project in netbeans

    - by Danny
    I'm running netbeans 6.7.1 on Ubuntu Karmic. On the services tab I added a new glassfish v3 prelude server, I installed it to my home directory using the download button. I started the server and opened localhost:4848 to verify I can get into the admin panel. Then I did file-new projct and created a new java web-web application. On the configuration step of the wizard it preselected glassfish v3 prelude and java ee 5. I accepted and did a test run. I ran the project just fine. So now I did file-new projecct and attempted to create a Java EE-ejb module. When I arrive to the server configuration stage of the wizard, it doesn't show any servers on the server dropdown list (so it's empty), it also doesn't see any version of java on the "java ee version" dropdown list. This also happens for the other "Java EE" project types. I can't seem to get my head around why I can make a new web application but not an ejb module. Can anyone provide any insight to why it might not be seeing that I have java or glassfish installed when I try to make a new java ee project but I see it when I try to make a java web project?

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  • How to create a generic C free function .

    - by nomemory
    I have some C structures related to a 'list' data structure. They look like this. struct nmlist_element_s { void *data; struct nmlist_element_s *next; }; typedef struct nmlist_element_s nmlist_element; struct nmlist_s { void (*destructor)(void *data); int (*cmp)(const void *e1, const void *e2); unsigned int size; nmlist_element *head; nmlist_element *tail; }; typedef struct nmlist_s nmlist; This way I can have different data types being hold in "nmlist_element-data" . The "constructor" (in terms of OOP) has the following signature: nmlist *nmlist_alloc(void (*destructor)(void *data)); Where "destructor" is specific function that de-allocated "data" (being hold by the nmlist_element). If I want to have a list containing integers as data, my "destructor" would like this: void int_destructor(void *data) { free((int*)data); } Still i find it rather "unfriendly" for me to write a destructor functions for every simple primitive data type. So is there a trick to write something like this ? (for primitives): void "x"_destructor(void *data, "x") { free(("x" *)data); } PS: I am not a macro fan myself, and in my short experience regarding C, i don't use them, unless necessary.

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  • Macro and array crossing

    - by Thomas
    I am having a problem with a lisp macro. I would like to create a macro which generate a switch case according to an array. Here is the code to generate the switch-case: (defun split-elem(val) `(,(car val) ',(cdr val))) (defmacro generate-switch-case (var opts) `(case ,var ,(mapcar #'split-elem opts))) I can use it with a code like this: (generate-switch-case onevar ((a . A) (b . B))) But when I try to do something like this: (defparameter *operators* '((+ . OPERATOR-PLUS) (- . OPERATOR-MINUS) (/ . OPERATOR-DIVIDE) (= . OPERATOR-EQUAL) (* . OPERATOR-MULT))) (defmacro tokenize (data ops) (let ((sym (string->list data))) (mapcan (lambda (x) (generate-switch-case x ops)) sym))) (tokenize data *operators*) I got this error: *** - MAPCAR: A proper list must not end with OPS. But I don't understand why. When I print the type of ops I get SYMBOL I was expecting CONS, is it related? Also, for my function tokenize how many times the lambda is evaluated (or the macro expanded)?

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  • Creating a complex tree model in Qt

    - by Zeke
    I'm writing an IRC Client (yes another one). Long story short. I'm writing a Server dialogue that keeps a list of this: Identity Networks Channels Addresses I have 3 different list views that will be for the Networks, Channels and Addresses. When the user changes the Identity (combo box). The network listview will lookup all the networks for that specific Identity. After it loads up the Networks it will automatically select the first network and then load all the channels and addresses for that specific network. The problem is I want to have 3 views for 1 model, to minimise all the memory and the loading of data. So that it makes it much easier to manage and not do a bunch of work. If you'd look at QColumnView it's the same exact thing. But I don't need it to be on one exact page since the views are on entirely different tabs to make it easier to go through the Server dialogue. I'm wondering what will be the best way to go about handling this complexity. The information is stored in a SQLite database. I already have the classes written to extract and store it. Just the modelling is the painful part of this solution.

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  • how to send on users profile page on selecting username( using json autosuggest script)

    - by I Like PHP
    i m using auto suggest using Ajax Json . now when a user select a user name , i want to send user on the link of that user name my json data is coming in this way { query:'hel', suggestions:["hello world","hell boy ","bac to hell"], data:["2","26","34"] } now what i want that user goes to http://userProfile.php?uid=26 on select username(suppose user select "hell boy") how to do this?? UPDATE: i describe what i m doing step by step i m using a searchbox using jquery ajax, when user write some text on input box , we show (suggest) value regarading their search STEP 1. when user write atleast(2 letter) <input type="text" name="q" id="query" />then a function(below) in invoked in which i send the value written on text box(eg. hell). <script type="text/javascript" language="javascript"> var options, a; jQuery(function(){ options = { serviceUrl:'rpc.php' }; var a = $('#query').autocomplete({ serviceUrl:'rpc.php', minChars:3, delimiter: /(,|;)\s*/, // regex or character maxHeight:400, width:300, zIndex: 9999, deferRequestBy: 0, //miliseconds }); }); </script> STEP 3: on rpc.php, i collect the data and show using JSON my final data come in below format { query:'hell', suggestions:["hello world","hell boy ","bac to hell"], data:["2","26","34"] } where suggestion list having username and data is userid( from user_tables). above data comes in a div (on frontend) where user name displayed in a list STEP 4: now if i select any username using uparrow, downarrow then that name is filled in input box, STEP 5: now what i want that when user select usename then page automatically goes to that user's profile section ( userprofile.php?uid=2)

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  • Any diff/merge tool that provides a report (metrics) of conflicts?

    - by cad
    CONTEXT: I am preparing a big C# merge using visual studio 2008 and TFS. I need to create a report with the files and the number of collisions (total changes and conflicts) for each file (and in total of course) PROBLEM: I cannot do it for two reasons (first one is solved): 1- Using TFS merge I can have access to the file comparison but I cannot export the list of conflicting files... I can only try to resolve the conflicts. (I have solved problem 1 using beyond compare. It allows me to export the file list) 2- Using TFS merge I can only access manually for each file to get the number of conflicts... but I have more than 800 files (and probably will have to repeat it in the close future so is not an option doing it manually) There are dozens of file comparison tools (http://en.wikipedia.org/wiki/Comparison_of_file_comparison_tools ) but I am not sure which one could (if any) give me these metrics. I have also read several forums and questions here but are more general questions (which diff tool is better) and I am looking for a very specific report. So my questions are: Is Visual Studio 2010 (using still TFS2008) capable of doing such reports/exportation? Is there any tool that provide this kind of metrics (Now I am trying Beyond Compare)

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  • How can I make this LinqToSQL query work? (SqlExecption)

    - by kversch
    The following code gives me an SqlException: OO theCourse = subject.Course; var students = dc.studentsCourses.Where(x = x.course == theCourse).Select(x = x.student); "Invalid object name 'dbo.studentsCourses'." I tried the following code instead but I also get an Exception. My original question was asked on Aardvark and can be read bellow: var allStudents = from s in dc.students select s; List thestudents = new List(); foreach (student s in allStudents) { if (s.courses.Contains(theCourse)) { thestudents.Add(s); } } I did a right click, "run custom tool" on my dbml and checked my names of my tables and entities. The project compiles but I get an Exception at runtime on this line: "if (s.courses.Contains(theCourse))" Any ideas? Original question on Aardvark: How do I do a LinqToSQL query that gives me this: I want to select all students that attended a certain lesson. The lesson is from a certain course. So select the course the lesson is from. Now select all the students that are following that course. There is a many-to-many relationship between the students and the courses table in my DB. I already extended my LINQ entities to be able to select student.Courses and course.Students using this method: http://www.codeproject.com/KB/linq/linq-to-sql-many-to-many.aspx

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  • [XPATH] Retrieve specific preceding sibling nodes attributes

    - by Matthieu BROUILLARD
    Is there an XPath way of recovering directly one specific attribute of preceding sibling nodes of an XML node using an XPath query? In the following example, I would like to retrieve the values of the alt attribute of each img nodes that precede the div element marked with the id=marker. <content> <img alt="1" src="file.gif" /> <img alt="2" src="file.gif" /> <img alt="3" src="file.gif" /> <img alt="4" src="file.gif" /> <div id='marker'></div> </content> For this example, I want to retrieve the values 1 2 3 4. I use the following XPath query //div[@id='marker']/preceding-sibling::img in order to retrieve the node list I want <img alt="1" src="file.gif"/> <img alt="2" src="file.gif"/> <img alt="3" src="file.gif"/> <img alt="4" src="file.gif"/> As it is a node list I can then iterate on the nodes to retrieve the attribute value I am looking for, but is there an XPath way of doing it? I would have expected to be able to write something like: //div[@id='marker']/preceding-sibling::img@alt or //div[@id='marker']/preceding-sibling@alt::img but I don't even know if it is possible once you have used an XPath Axe like preceding-sibling.

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  • Common Lisp condition system for transfer of control

    - by Ken
    I'll admit right up front that the following is a pretty terrible description of what I want to do. Apologies in advance. Please ask questions to help me explain. :-) I've written ETLs in other languages that consist of individual operations that look something like: // in class CountOperation IEnumerable<Row> Execute(IEnumerable<Row> rows) { var count = 0; foreach (var row in rows) { row["record number"] = count++; yield return row; } } Then you string a number of these operations together, and call The Dispatcher, which is responsible for calling Operations and pushing data between them. I'm trying to do something similar in Common Lisp, and I want to use the same basic structure, i.e., each operation is defined like a normal function that inputs a list and outputs a list, but lazily. I can define-condition a condition (have-value) to use for yield-like behavior, and I can run it in a single loop, and it works great. I'm defining the operations the same way, looping through the inputs: (defun count-records (rows) (loop for count from 0 for row in rows do (signal 'have-value :value `(:count ,count @,row)))) The trouble is if I want to string together several operations, and run them. My first attempt at writing a dispatcher for these looks something like: (let ((next-op ...)) ;; pick an op from the set of all ops (loop (handler-bind ((have-value (...))) ;; records output from operation (setq next-op ...) ;; pick a new next-op (call next-op))) But restarts have only dynamic extent: each operation will have the same restart names. The restart isn't a Lisp object I can store, to store the state of a function: it's something you call by name (symbol) inside the handler block, not a continuation you can store for later use. Is it possible to do something like I want here? Or am I better off just making each operation function explicitly look at its input queue, and explicitly place values on the output queue?

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  • Python: Convert format string to regular expression

    - by miracle2k
    The users of my app can configure the layout of certain files via a format string. For example, the config value the user specifies might be: layout = '%(group)s/foo-%(locale)s/file.txt' I now need to find all such files that already exist. This seems easy enough using the glob module: glob_pattern = layout % {'group': '*', 'locale': '*'} glob.glob(glob_pattern) However, now comes the hard part: Given the list of glob results, I need to get all those filename-parts that matched a given placeholder, for example all the different "locale" values. I thought I would generate a regular expression for the format string that I could then match against the list of glob results (or then possibly skipping glob and doing all the matching myself). But I can't find a nice way to create the regex with both the proper group captures, and escaping the rest of the input. For example, this might give me a regex that matches the locales: regex = layout % {'group': '.*', 'locale': (.*)} But to be sure the regex is valid, I need to pass it through re.escape(), which then also escapes the regex syntax I have just inserted. Calling re.escape() first ruins the format string. I know there's fnmatch.translate(), which would even give me a regex - but not one that returns the proper groups. Is there a good way to do this, without a hack like replacing the placeholders with a regex-safe unique value etc.? Is there possibly some way (a third party library perhaps?) that allows dissecting a format string in a more flexible way, for example splitting the string at the placeholder locations?

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  • Adjust static value into dynamic (javascript) value possible in Sharepoint allitems.aspx page?

    - by lerac
    <SharePoint:SPDataSource runat="server" IncludeHidden="true" SelectCommand="&lt;View&gt;&lt;Query&gt;&lt;OrderBy&gt;&lt;FieldRef Name=&quot;EventDate&quot;/&gt;&lt;/OrderBy&gt;&lt;Where&gt;&lt;Contains&gt;&lt;FieldRef Name=&quot;lawyer_x0020_1&quot;/&gt;&lt;Value Type=&quot;Note&quot;&gt;F. Sanches&lt;/Value&gt;&lt;/Contains&gt;&lt;/Where&gt;&lt;/Query&gt;&lt;/View&gt;" id="datasource1" DataSourceMode="List" UseInternalName="true"><InsertParameters><asp:Parameter DefaultValue="{ANUMBER}" Name="ListID"></asp:Parameter> This codeline is just one line of the allitems.aspx of a sharepoint list item. It only displays items where lawyer 1 = F. Sanches. Before I start messing around with the .ASPX page I wonder if it possible to change F. Sanches (in the code) into a dynamical variable (from a javascript value or something else that can be used to place the javascript value in there dynamically). If I put any javascript code in the line it will not work. P.S. Ignore ANUMBER part in code. Let say to make it simple I have javascript variable like this (now static but with my other code it is dynamic). It would be an achievement if it would place a static javascript variable. <SCRIPT type=text/javascript>javaVAR = "P. Janssen";</script> If Yes -- how? If No -- Thank you!

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  • When are predicates appropriate and what is the best pattern for usage

    - by Maxim Gershkovich
    When are predicates appropriate and what is the best pattern for usage? What are the advantages of predicates? It seems to me like most cases where a predicate can be employed a tight loop would accomplish the same functionality? I don’t see a reusability argument given you will probably only implement a predicate in one method right? They look and feel nice but besides that they seem like you would only employ them when you need a quick hack on the collection classes? UPDATE But why would you be rewriting the tight loop again and again? In my mind/code when it comes to collections I always end up with something like Class Person End Class Class PersonList Inherits List(Of Person) Function FindByName(Name) as Person tight loop.... End Function End Class @Ani By that same logic I could implement the method as such Class PersonList Inherits List(Of Person) Function FindByName(Name) as PersonList End Function Function FindByAge(Age) as PersonList End Function Function FindBySocialSecurityNumber(SocialSecurityNumber) as PersonList End Function End Class And call it as such Dim res as PersonList = MyList.FindByName("Max").FindByAge(25).FindBySocialSecurityNumber(1234) and the result along with the amount of code and its reusability is largely the same, no? I am not arguing just trying to understand.

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  • Avoiding a fork()/SIGCHLD race condition

    - by larry
    Please consider the following fork()/SIGCHLD pseudo-code. // main program excerpt for (;;) { if ( is_time_to_make_babies ) { pid = fork(); if (pid == -1) { /* fail */ } else if (pid == 0) { /* child stuff */ print "child started" exit } else { /* parent stuff */ print "parent forked new child ", pid children.add(pid); } } } // SIGCHLD handler sigchld_handler(signo) { while ( (pid = wait(status, WNOHANG)) > 0 ) { print "parent caught SIGCHLD from ", pid children.remove(pid); } } In the above example there's a race-condition. It's possible for "/* child stuff */" to finish before "/* parent stuff */" starts which can result in a child's pid being added to the list of children after it's exited, and never being removed. When the time comes for the app to close down, the parent will wait endlessly for the already-finished child to finish. One solution I can think of to counter this is to have two lists: started_children and finished_children. I'd add to started_children in the same place I'm adding to children now. But in the signal handler, instead of removing from children I'd add to finished_children. When the app closes down, the parent can simply wait until the difference between started_children and finished_children is zero. Another possible solution I can think of is using shared-memory, e.g. share the parent's list of children and let the children .add and .remove themselves? But I don't know too much about this. EDIT: Another possible solution, which was the first thing that came to mind, is to simply add a sleep(1) at the start of /* child stuff */ but that smells funny to me, which is why I left it out. I'm also not even sure it's a 100% fix. So, how would you correct this race-condition? And if there's a well-established recommended pattern for this, please let me know! Thanks.

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  • Problem declaring and calling internal metthods

    - by Martin
    How do I declare and use small helper functions inside my normal methods ? In on of my objective-c methods I need a function to find an item within a string -(void) Onlookjson:(id) sender{ NSString * res = getKeyValue(res, @"Birth"); } I came up with a normal C type declaration for helper function getKeyvalue like this NSString * getKeyvalue(NSString * s, NSString key){ NSString *trm = [[s substringFromIndex:2] substringToIndex:[s length]-3]; NSArray *list = [trm componentsSeparatedByString:@";"]; .... NSString res; res = [list objectAtIndex:1]; ... return res; } Input data string: { Birth = ".."; Death = "..."; ... } Anyway I get an exception "unrecognized selector sent to instance" for any of the two first lines in the helper function How do I declare helper functions that are just to be used internally and how to call them safely ? regards Martin

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  • are these css classes names good?

    - by metal-gear-solid
    See section /* Common Classes */ of this page. http://webdesign.about.com/od/css/a/master_stylesht_2.htm are these css classes good, to use in any project? in terms of semantic? /* Common Classes */ .clear { clear: both; } .floatLeft { float: left; } .floatRight { float: right; } .textLeft { text-align: left; } .textRight { text-align: right; } .textCenter { text-align: center; } .textJustify { text-align: justify; } .blockCenter { display: block; margin-left: auto; margin-right: auto; } /* remember to set width */ .bold { font-weight: bold; } .italic { font-style: italic; } .underline { text-decoration: underline; } .noindent { margin-left: 0; padding-left: 0; } .nomargin { margin: 0; } .nopadding { padding: 0; } .nobullet { list-style: none; list-style-image: none; }

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  • systematizing error codes for a web app in php?

    - by user151841
    I'm working on a class-based php web app. I have some places where objects are interacting, and I have certain situations where I'm using error codes to communicate to the end user -- typically when form values are missing or invalid. These are situations where exceptions are unwarranted ( and I'm not sure I could avoid the situations with exceptions anyways). In one object, I have some 20 code numbers, each of which correspond to a user-facing message, and a admin/developer-facing message, so both parties know what's going on. Now that I've worked over the code several times, I find that it's difficult to quickly figure out what code numbers in the series I've already used, so I accidentally create conflicting code numbers. For instance, I just did that today with 12, 13, 14 and 15. How can I better organize this so I don't create conflicting error codes? Should I create one singleton class, errorCodes, that has a master list of all error codes for all classes, systematizing them across the whole web app? Or should each object have its own set of error codes, when appropriate, and I just keep a list in the commentary of the object, to use and update that as I go along?

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  • How can I make keyword order more relevant in my search?

    - by Atomiton
    In my database, I have a keywords field that stores a comma-delimited list of keywords. For example, a Shrek doll might have the following keywords: ogre, green, plush, hero, boys' toys A "Beanie Baby" doll ( that happens to be an ogre ) might have: beanie baby, kids toys, beanbag toys, soft, infant, ogre (That's a completely contrived example.) What I'd like to do is if the consumer searches for "ogre" I'd like the "Shrek" doll to come up higher in the search results. My content administrator feels that if the keyword is earlier in the list, it should get a higher ranking. ( This makes sense to me and it makes it easy for me to let them control the search result relevance ). Here's a simplified query: SELECT p.ProductID AS ContentID , p.ProductName AS Title , p.ProductCode AS Subtitle , 100 AS Rank , p.ProductKeywords AS Keywords FROM Products AS p WHERE FREETEXT( p.ProductKeywords, @SearchPredicate ) I'm thinking something along the lines of replacing the RANK with: , 200 - INDEXOF(@SearchTerm) AS Rank This "should" rank the keyword results by their relevance I know INDEXOF isn't a SQL command... but it's something LIKE that I would like to accomplish. Am I approaching this the right way? Is it possible to do something like this? Does this make sense?

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