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• Using a regex pattern to find revision numbers from a svn merge

  - by zyzy

  svn diff -rXX:HEAD Will give me a format like this, if there has been a merge between those revisions: Merged /<branch>:rXXX,XXX-XXX or Merged /<branch>:rXXX I'm not very familiar with regex and am trying to put together a pattern which will match all the numbers (merged revision numbers) AFTER matching the "Merged /branch:r" part. So far I have this to match the first part: [Mm]erged.*[a-zA-Z]:r Thanks in adv. for the help :)

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• SQl Server error handling pattern

  - by Patrick Honorez

  Hi all. I am not an expert on SQl Server. Is this a valid pattern for handling errors in a batch of SELECT, INSERT...in SQl SERVER ? (I use v.2008) BEGIN TRANSACTION BEGIN TRY -- statement 1 -- statement 2 -- statement 3 COMMIT TRANSACTION END TRY BEGIN CATCH ROLLBACK TRANSACTION END CATCH Thanks

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• Finding all CLASSPATH resources matching a pattern

  - by binil

  I want to read a bunch of text files, by loading them as resources using the context classloader. URL url = Thread.currentThread() .getContextClassloader() .getResource("folder/foo.txt"); Is there some way to get a list of resources whose names match a given pattern? For eg: URL[] matchingUrls = someLibrary.getMatchingResources("folder/*.txt"); Libraries like Spring can scan the classpath to find classes with a given annotation, so I am wondering if there something similar to load a bunch of resources.

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• Sed. How change line next to specific pattern

  - by kirill

  My file is: DIVIDER Sometext_string many lines of random text DIVIDER Another_Sometext_string many many lines DIVIDER Third_sometext_string .... How change lines following DIVIDER pattern Result must be: DIVIDER [begin]Sometext_string[end] many lines of random text DIVIDER [begin]Another_Sometext_string[end] many many lines DIVIDER [begin]Third_sometext_string[end] ....

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• Is Core Data using the Ghost pattern?

  - by dontWatchMyProfile

  All this fault and faulting stuff appears to look pretty much like the Ghost pattern. Is that the same thing?

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• Singleton Pattern Implementation Issues?

  - by locky28

  Hi I am revising for an exam and need to know some implementation issues with the singleton pattern. they do not need to be too complex just basic things that would affect a developers decision to include them, Thanks P.S. Could any code examples be given in Java thanks.

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• Pattern match and replace in Javascript

  - by T_t

  There is something in my mind: In a web page,there are lots of things we can see from our browser.One of them is text. Now i have some patterns,"abc","hello",or some other strings.In the text, i want to find all the patterns and change the color or background-color of them. Like this: text: what a wonderful day! pattern: "a","day" resulet: what a wonderful day! How can solve this whit Javascript?

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• ASP.net Integration Pattern - examples

  - by nettguy

  Recently lot of interviewers are asking "What are the integration patterns are you familiar with?". I know design patterns,what is integration pattern then?

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• FluentNHibernate Unit Of Work / Repository Design Pattern Questions

  - by Echiban

  Hi all, I think I am at a impasse here. I have an application I built from scratch using FluentNHibernate (ORM) / SQLite (file db). I have decided to implement the Unit of Work and Repository Design pattern. I am at a point where I need to think about the end game, which will start as a WPF windows app (using MVVM) and eventually implement web services / ASP.Net as UI. Now I already created domain objects (entities) for ORM. And now I don't know how should I use it outside of ORM. Questions about it include: Should I use ORM entity objects directly as models in MVVM? If yes, do I put business logic (such as certain values must be positive and be greater than another Property) in those entity objects? It is certainly the simpler approach, and one I am leaning right now. However, will there be gotchas that would trash this plan? If the answer above is no, do I then create a new set of classes to implement business logic and use those as Models in MVVM? How would I deal with the transition between model objects and entity objects? I guess a type converter implementation would work well here. Now I followed this well written article to implement the Unit Of Work pattern. However, due to the fact that I am using FluentNHibernate instead of NHibernate, I had to bastardize the implementation of UnitOfWorkFactory. Here's my implementation: using System; using FluentNHibernate.Cfg; using FluentNHibernate.Cfg.Db; using NHibernate; using NHibernate.Cfg; using NHibernate.Tool.hbm2ddl; namespace ELau.BlindsManagement.Business { public class UnitOfWorkFactory : IUnitOfWorkFactory { private static readonly string DbFilename; private static Configuration _configuration; private static ISession _currentSession; private ISessionFactory _sessionFactory; static UnitOfWorkFactory() { // arbitrary default filename DbFilename = "defaultBlindsDb.db3"; } internal UnitOfWorkFactory() { } #region IUnitOfWorkFactory Members public ISession CurrentSession { get { if (_currentSession == null) { throw new InvalidOperationException(ExceptionStringTable.Generic_NotInUnitOfWork); } return _currentSession; } set { _currentSession = value; } } public ISessionFactory SessionFactory { get { if (_sessionFactory == null) { _sessionFactory = BuildSessionFactory(); } return _sessionFactory; } } public Configuration Configuration { get { if (_configuration == null) { Fluently.Configure().ExposeConfiguration(c => _configuration = c); } return _configuration; } } public IUnitOfWork Create() { ISession session = CreateSession(); session.FlushMode = FlushMode.Commit; _currentSession = session; return new UnitOfWorkImplementor(this, session); } public void DisposeUnitOfWork(UnitOfWorkImplementor adapter) { CurrentSession = null; UnitOfWork.DisposeUnitOfWork(adapter); } #endregion public ISession CreateSession() { return SessionFactory.OpenSession(); } public IStatelessSession CreateStatelessSession() { return SessionFactory.OpenStatelessSession(); } private static ISessionFactory BuildSessionFactory() { ISessionFactory result = Fluently.Configure() .Database( SQLiteConfiguration.Standard .UsingFile(DbFilename) ) .Mappings(m => m.FluentMappings.AddFromAssemblyOf<UnitOfWorkFactory>()) .ExposeConfiguration(BuildSchema) .BuildSessionFactory(); return result; } private static void BuildSchema(Configuration config) { // this NHibernate tool takes a configuration (with mapping info in) // and exports a database schema from it _configuration = config; new SchemaExport(_configuration).Create(false, true); } } } I know that this implementation is flawed because a few tests pass when run individually, but when all tests are run, it would fail for some unknown reason. Whoever wants to help me out with this one, given its complexity, please contact me by private message. I am willing to send some $$$ by Paypal to someone who can address the issue and provide solid explanation. I am new to ORM, so any assistance is appreciated.

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• Combining template method with strategy

  - by Mekswoll

  An assignment in my software engineering class is to design an application which can play different forms a particular game. The game in question is Mancala, some of these games are called Wari or Kalah. These games differ in some aspects but for my question it's only important to know that the games could differ in the following: The way in which the result of a move is handled The way in which the end of the game is determined The way in which the winner is determined The first thing that came to my mind to design this was to use the strategy pattern, I have a variation in algorithms (the actual rules of the game). The design could look like this: I then thought to myself that in the game of Mancala and Wari the way the winner is determined is exactly the same and the code would be duplicated. I don't think this is by definition a violation of the 'one rule, one place' or DRY principle seeing as a change in rules for Mancala wouldn't automatically mean that rule should be changed in Wari as well. Nevertheless from the feedback I got from my professor I got the impression to find a different design. I then came up with this: Each game (Mancala, Wari, Kalah, ...) would just have attribute of the type of each rule's interface, i.e. WinnerDeterminer and if there's a Mancala 2.0 version which is the same as Mancala 1.0 except for how the winner is determined it can just use the Mancala versions. I think the implementation of these rules as a strategy pattern is certainly valid. But the real problem comes when I want to design it further. In reading about the template method pattern I immediately thought it could be applied to this problem. The actions that are done when a user makes a move are always the same, and in the same order, namely: deposit stones in holes (this is the same for all games, so would be implemented in the template method itself) determine the result of the move determine if the game has finished because of the previous move if the game has finished, determine who has won Those three last steps are all in my strategy pattern described above. I'm having a lot of trouble combining these two. One possible solution I found would be to abandon the strategy pattern and do the following: I don't really see the design difference between the strategy pattern and this? But I am certain I need to use a template method (although I was just as sure about having to use a strategy pattern). I also can't determine who would be responsible for creating the TurnTemplate object, whereas with the strategy pattern I feel I have families of objects (the three rules) which I could easily create using an abstract factory pattern. I would then have a MancalaRuleFactory, WariRuleFactory, etc. and they would create the correct instances of the rules and hand me back a RuleSet object. Let's say that I use the strategy + abstract factory pattern and I have a RuleSet object which has algorithms for the three rules in it. The only way I feel I can still use the template method pattern with this is to pass this RuleSet object to my TurnTemplate. The 'problem' that then surfaces is that I would never need my concrete implementations of the TurnTemplate, these classes would become obsolete. In my protected methods in the TurnTemplate I could just call ruleSet.determineWinner(). As a consequence, the TurnTemplate class would no longer be abstract but would have to become concrete, is it then still a template method pattern? To summarize, am I thinking in the right way or am I missing something easy? If I'm on the right track, how do I combine a strategy pattern and a template method pattern? This is part of a homework assignment but I'm not looking to be gifted the answer, I have deliberately been very verbose in my question to show that I have thought about it before coming here to ask a question

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• good way to implement NotSpecification: isSpecialCaseOf?

  - by koen

  I'm implementing the specification pattern. The NotSpecification seems simple at first: NotSpecification.IsSpecialCaseOf(otherSpecification) return !this.specification.isSpecialCaseOf(otherSpecification) But it doesn't work for all Specifications: Not(LesserThan(5)).IsSpecialCaseOf(GreaterThan(4)) This should be true. So far I think that the only way to accomplish the isSpecialCaseOf the NotSpecification is to implement the remainderUnsatisfiedBy (partial subsumption in the paper on the specification pattern). But maybe I am missing something more simple or a logical insight that makes this unnecessary. Question: Is there another way of implementing this by not using remainderUnsatisfiedBy?

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• Munin email notification

  - by Prashanth

  I am trying to get munin to notify me via email. I have configured munin and it reports critical and warning values but no alerts are being sent neither is any script being called. Can you please help me out with this? I have included part of the munin.conf below # Drop [email protected] and [email protected] an email everytime # something changes (OK -> WARNING, CRITICAL -> OK, etc) #contact.someuser.command mail -s "Munin notification" [email protected]\ contact.prashanth.command echo "Munin notification" | sendmail -t [email protected] contact.prashanth.always_send warning critical contact.root.command echo "Munin notification" | sendmail -t [email protected] contact.root.always_send warning critical contact.pipevia.command | /home/prashanth/script.sh /home/prashanth/script.sh None of this works. What am i missing here and why are emails not being sent? Thanks in advance. here is the munin-limits.log 2011/09/26 14:58:12 Opened log file 2011/09/26 14:58:12 [INFO] Starting munin-limits, getting lock /var/run/munin/munin-limits.lock 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 722. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 725. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 740. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 754. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 759. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $text in length at /usr/share/perl5/Munin/Master/LimitsOld.pm line 774. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $res[3] in join or string at /usr/share/perl5/Munin/Master/LimitsOld.pm line 777. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 722. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 725. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 740. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 754. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 759. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $text in length at /usr/share/perl5/Munin/Master/LimitsOld.pm line 774. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $res[15] in join or string at /usr/share/perl5/Munin/Master/LimitsOld.pm line 777. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 722. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 725. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 740. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 754. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 759. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $text in length at /usr/share/perl5/Munin/Master/LimitsOld.pm line 774. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $res[1] in join or string at /usr/share/perl5/Munin/Master/LimitsOld.pm line 777. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 722. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 725. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 740. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 754. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $a[0] in pattern match (m//) at /usr/share/perl5/Munin/Master/LimitsOld.pm line 759. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $text in length at /usr/share/perl5/Munin/Master/LimitsOld.pm line 774. 2011/09/26 14:58:12 [PERL WARNING] Use of uninitialized value $res[1] in join or string at /usr/share/perl5/Munin/Master/LimitsOld.pm line 777. 2011/09/26 14:58:12 Baz? 2011/09/26 14:58:12 [INFO] munin-limits finished (0.02 sec) 2011/09/26 14:58:12 Command "prashanth" stderr: Munin notification - this is a test mail from the user prashanth | sendmail -t [email protected]

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• testing dao with hibernate genericdao pattern with spring.Headache

  - by black sensei

  Hello good fellas! in my journey of learning hibernate i came across an article on hibernate site. i' learning spring too and wanted to do certain things to discover the flexibility of spring by letting you implement you own session.yes i don't want to use the hibernateTemplate(for experiment). and i'm now having a problem and even the test class.I followed the article on the hibernate site especially the section an "implementation with hibernate" so we have the generic dao interface : public interface GenericDAO<T, ID extends Serializable> { T findById(ID id, boolean lock); List<T> findAll(); List<T> findByExample(T exampleInstance); T makePersistent(T entity); void makeTransient(T entity); } it's implementation in an abstract class that is the same as the one on the web site.Please refer to it from the link i provide.i'll like to save this post to be too long now come my dao's messagedao interface package com.project.core.dao; import com.project.core.model.MessageDetails; import java.util.List; public interface MessageDAO extends GenericDAO<MessageDetails, Long>{ //Message class is on of my pojo public List<Message> GetAllByStatus(String status); } its implementation is messagedaoimpl: public class MessageDAOImpl extends GenericDAOImpl <Message, Long> implements MessageDAO { // mySContainer is an interface which my HibernateUtils implement mySContainer sessionManager; /** * */ public MessageDAOImpl(){} /** * * @param sessionManager */ public MessageDAOImpl(HibernateUtils sessionManager){ this.sessionManager = sessionManager; } //........ plus other methods } here is my HibernatUtils public class HibernateUtils implements SessionContainer { private final SessionFactory sessionFactory; private Session session; public HibernateUtils() { this.sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory(); } public HibernateUtils(SessionFactory sessionFactory) { this.sessionFactory = sessionFactory; } /** * * this is the function that return a session.So i'm free to implements any type of session in here. */ public Session requestSession() { // if (session != null || session.isOpen()) { // return session; // } else { session = sessionFactory.openSession(); // } return session; } } So in my understanding while using spring(will provide the conf), i'ld wire sessionFactory to my HiberbernateUtils and then wire its method RequestSession to the Session Property of the GenericDAOImpl (the one from the link provided). here is my spring config core.xml <bean id="sessionManager" class="com.project.core.dao.hibernate.HibernateUtils"> <constructor-arg ref="sessionFactory" /> </bean> <bean id="messageDao" class="com.project.core.dao.hibernate.MessageDAOImpl"> <constructor-arg ref="sessionManager"/> </bean> <bean id="genericDAOimpl" class="com.project.core.dao.GenericDAO"> <property name="session" ref="mySession"/> </bean> <bean id="mySession" factory-bean="com.project.core.dao.SessionContainer" factory-method="requestSession"/> now my test is this public class MessageDetailsDAOImplTest extends AbstractDependencyInjectionSpringContextTests{ HibernateUtils sessionManager = (HibernateUtils) applicationContext.getBean("sessionManager"); MessageDAO messagedao =(MessageDAO) applicationContext.getBean("messageDao"); static Message[] message = new Message[] { new Message("text",1,"test for dummies 1","1234567890","Pending",new Date()), new Message("text",2,"test for dummies 2","334455669990","Delivered",new Date()) }; public MessageDAOImplTest() { } @Override protected String[] getConfigLocations(){ return new String[]{"file:src/main/resources/core.xml"}; } @Test public void testMakePersistent() { System.out.println("MakePersistent"); messagedao.makePersistent(message[0]); Session session = sessionManager.RequestSession(); session.beginTransaction(); MessageDetails fromdb = ( Message) session.load(Message.class, message[0].getMessageId()); assertEquals(fromdb.getMessageId(), message[0].getMessageId()); assertEquals(fromdb.getDateSent(),message.getDateSent()); assertEquals(fromdb.getGlobalStatus(),message.getGlobalStatus()); assertEquals(fromdb.getNumberOfPages(),message.getNumberOfPages()); } i'm having this error exception in constructor testMakePersistent(java.lang.NullPointerException at com.project.core.dao.hibernate.MessageDAOImplTest) with this stack : at com.project.core.dao.hibernate.MessageDAOImplTest.(MessageDAOImplTest.java:28) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at junit.framework.TestSuite.createTest(TestSuite.java:61) at junit.framework.TestSuite.addTestMethod(TestSuite.java:283) at junit.framework.TestSuite.(TestSuite.java:146) at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.run(JUnitTestRunner.java:481) at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.launch(JUnitTestRunner.java:1031) at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.main(JUnitTestRunner.java:888) )) How to actually make this one work.I know this is a lot to stuffs and i'm thanking you for reading it.Please give me a solution.How would you do this? thanks

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• Java regex patterns - compile time constants or instance members?

  - by KepaniHaole

  Currently, I have a couple of singleton objects where I'm doing matching on regular expressions, and my Patterns are defined like so: class Foobar { private final Pattern firstPattern = Pattern.compile("some regex"); private final Pattern secondPattern = Pattern.compile("some other regex"); // more Patterns, etc. private Foobar() {} public static Foobar create() { /* singleton stuff */ } } But I was told by someone the other day that this is bad style, and Patterns should always be defined at the class level, and look something like this instead: class Foobar { private static final Pattern FIRST_PATTERN = Pattern.compile("some regex"); private static final Pattern SECOND_PATTERN = Pattern.compile("some other regex"); // more Patterns, etc. private Foobar() {} public static Foobar create() { /* singleton stuff */ } } The lifetime of this particular object isn't that long, and my main reason for using the first approach is because it doesn't make sense to me to hold on to the Patterns once the object gets GC'd. Any suggestions / thoughts?

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• How to show that the double-checked-lock pattern with Dictionary's TryGetValue is not threadsafe in

  - by Amir

  Recently I've seen some C# projects that use a double-checked-lock pattern on a Dictionary. Something like this: private static readonly object _lock = new object(); private static volatile IDictionary<string, object> _cache = new Dictionary<string, object>(); public static object Create(string key) { object val; if (!_cache.TryGetValue(key, out val)) { lock (_lock) { if (!_cache.TryGetValue(key, out val)) { val = new object(); // factory construction based on key here. _cache.Add(key, val); } } } return val; } This code is incorrect, since the Dictionary can be "growing" the collection in _cache.Add() while _cache.TryGetValue (outside the lock) is iterating over the collection. It might be extremely unlikely in many situations, but is still wrong. Is there a simple program to demonstrate that this code fails? Does it make sense to incorporate this into a unit test? And if so, how?

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• Modelling multiple simultaneous states

  - by James P.

  How can you go about modelling an object that can have multiple simultaneous states? For example, you could have a person that's waiting for a bus. That's one state. But they could also be reading a newspaper while waiting for the bus. Furthermore, they could be thinking about something while reading the newspaper. They could also be sniffing their nose because they have a cold. That's a four states in all taking place at the same time. Obviously using booleans would be tedious and unflexible. Also, a conventional state pattern would mean that states are exclusive and can't be simultaneous in nature. The only thing I can think of is a State pattern combined with a Composite. Would this do or is there a way of taking things further?

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• Replace whitespaces using PHP preg_replace function ignoring quoted strings

  - by Saiful

  Look at the following string: SELECT column1 , column2, column3 FROM table1 WHERE column1 = 'text, "FROM" \'from\\\' x' AND column2 = "sample text 'where' \"where\\\" " AND ( column3 = 5 ) I need to escape unnecessary white space characters from the string like: removing white space from beginning and ending position of , ( ) etc removing newline (\r\n) and tabs (\t) But one thing. The remove process could not remove white spaces from the quoted string like: 'text, "FROM" \'from\\' x' "sample text 'where' \"where\\" " etc. i need to use the PHP function: preg_replace($pattern, $replacement, $string); So what will be the value of $pattern and $replacement where the value of $string is the given SQL.

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• creational pattern for instances depending on multiple subclass instances

  - by markusw

  I have a problem, for that I was not able to identify a suitable design pattern. I want to create instances depending on a given type that has been passed to a factory method. What I am doing until now is the following: T create(SuperType x) { if (x instanceof SubType1) { // do some stuff and return a new SubType extends T } else if (x instanceof SubType2) { // do some stuff and return a new SubType extends T } else if ... } else { throw new UnSupportedOperationException("nothing defined for " + x); } } It seems not to be best pratice for me. Has anybody an idea how to solve this in a better way?

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• design pattern tools to use?

  - by ajsie

  i have noticed that every area has some tools you can use to make things easier. eg. css = dreamweaver doctrine/propel = orm designer // you dont have to hardcore code schemas manually and remembering all the syntax/variables mysql = mysql workbench // the same etc. in this way you get aided and dont have to type things the hard way, and can learn the structure, but then use GUI tools to help you develop faster. now i'm learning design patterns (singleton, factory, command, memento etc) and im wondering if there are some kind of tools you can use that will help you develop faster. i dont know exactly what tools i'm trying to find, just helping me when coding with design patterns (schema drawings? references?) are there any?

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• The best JSF coding pattern for editing JPA entities using @RequestScoped only

  - by AlanObject

  I am in a project where I will write a lot of pages like this, so I want to use the most efficient (to write) coding pattern. Background: In the past I have used CODI's @ViewAccessScoped to preserve state between requests, and more recently I have started using flash scoped objects to save state. I can't use JSF @ViewScoped because I use CDI and they don't play well together. So I want to see if I can do this with only @RequestScoped backing beans. The page is designed like this (the p namespace is Primefaces): <f:metadata> <f:viewParam name="ID" value="#{backing.id}" /> </f:metadata> .... <h1>Edit Object Page</h1> <h:form id="formObj" rendered="#{backing.accessOK}"> <p:panelGrid columns="2"> <h:outputLabel value="Field #1:"/> <p:inputText value="#{backing.record.field1}" /> (more input fields) <h:outputLabel value="Action:" /> <h:panelGroup> <p:commandButton value="Save" action="#{backing.save}" /> <p:commandButton value="Cancel" action="backing.cancel" /> </h:panelGroup> </p:panelGrid> <p:messages showDetail="true" showSummary="true" /> </h:form> If the page is requested, the method accessOK() has the ability to keep the h:form from being rendered. Instead, the p:messages is shown with whatever FacesMessage(s) the accessOK() method cares to set. The pattern for the bean backing looks like this: @Named @RequestScoped public class Backing { private long id; private SomeJPAEntity record; private Boolean accessOK; public long getId() { return id; } public void setId(long value) { id = value; } public boolean accessOK() { if (accessOK != null) return accessOK; if (getRecord() == null) { // add a FacesMessage that explains the record // does not exist return accessOK = false; // note single = } // do any other access checks, such as write permissions return accessOK = true; } public SomeJPAEntity getRecord() { if (record != null) return record; if (getId() > 0) record = // get the record from DB else record = new SomeJPAEntity(); return record; } public String execute() { if (!accessOK()) return null; // bad edit // do other integrity checks here. If fail, set FacesMessages // and return null; if (getId() > 0) // merge the record back into the data base else // persist the record } } Here is what goes wrong with this model. When the Save button is clicked, a new instance of Backing is built, and then there are a lot of calls to the getRecord() getter before the setID() setter is called. So the logic in getRecord() breaks because it cannot rely on the id property being valid when it is called. When this was a @ViewAccessScoped (or ViewScoped) backing bean, then both the id and record properties are already set when the form is processed with the commandButton. Alternatively you can save those properties in flash storage but that has its own problems I want to avoid. So is there a way to make this programming model work within the specification?

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• Magento Onepage Success Conversion Tracking Design Pattern

  - by user1734954

  My intent is to track conversions through multiple channels by inserting third party javascript (for example google analytics, optimizely, pricegrabber etc.) into the footer of onepage success . I've accomplished this by adding a block to the footer reference inside of the checkout success node within local.xml and everything works appropriately. My questions are more about efficiency and extensibility. It occurred to me that it would be better to combine all of the blocks into a single block reference and then use a various methods acting on a single call to the various related models to provide the data needed for insertion into the javascript for each of the conversion tracking scripts. Some examples of the common data that conversion tracking may rely on(pseudo): Order ID , Order Total, Order.LineItem.Name(foreach) and so on Currently for each of the scripts I've made a call to the appropriate model passing the customers last order id as the load value and the calling a get() assigning the return value to a variable and then iterating through the data to match the values with the expectations of the given third party service. All of the data should be pulled once when checkout is complete each third party services may expect different data in different formats Here is an example of one of the conversion tracking template files which loads at the footer of checkout success. $order = Mage::getModel('sales/order')->loadByIncrementId(Mage::getSingleton('checkout/session')->getLastRealOrderId()); $amount = number_format($order->getGrandTotal(),2); $customer = Mage::helper('customer')->getCustomer()->getData(); ?> <script type="text/javascript"> popup_email = '<?php echo($customer['email']);?>'; popup_order_number = '<?php echo $this->getOrderId() ?>'; </script> <!-- PriceGrabber Merchant Evaluation Code --> <script type="text/javascript" charset="UTF-8" src="https://www.pricegrabber.com/rating_merchrevpopjs.php?retid=<something>"></script> <noscript><a href="http://www.pricegrabber.com/rating_merchrev.php?retid=<something>" target=_blank> <img src="https://images.pricegrabber.com/images/mr_noprize.jpg" border="0" width="272" height="238" alt="Merchant Evaluation"></a></noscript> <!-- End PriceGrabber Code --> Having just a single piece of code like this is not that big of a deal, but we are doing similar things with a number of different third party services. Pricegrabber is one of the simpler examples. A more sophisticated tracking service expects a comma separated list of all of the product names, ids, prices, categories , order id etc. I would like to make it all more manageable so my idea to do the following: combine all of the template files into a single file Develop a helper class or library to deliver the data to the conversion template Goals Include Extensibility Minimal Model Calls Minimal Method Calls The Questions 1. Is a Mage helper the best route to take? 2. Is there any design pattern you may recommend for the "helper" class? 3. Why would this the design pattern you've chosen be best for this instance?

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• [Erlang - trace] How to trace for all functions in an Erlang module except for one?

  - by Dlf

  I wanted to trace for all functions in an erlang module, with dbg:tpl, but one of the internal functions took up 95% of the trace file. I then wanted to exclude only that single function and found that it was not as easy as I thought it would be. I know there are great pattern matching possibilities for arguments when tracing. Is there a similar possibility to apply pattern matching for functions? eg.: {'=/=', '$2', function_name} I am open for outside-the-box solutions as well! Thank You!

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• Regular expression one or more times JAVA

  - by user1381564

  Hi i am trying to match a string against a pattern this is the possible string signal CS, NS, dl: stateType := writeOrRead0; signal CS, pS : stateType := writeOrRead0; signal dS : stateType := writeOrRead0; i am only concerned with the pattern as far as the first colon. but the number of signals define can be more than one it could be three or four even this is the regular expression i have ^signal\\s*(\\w+),*\\s*(\\w+)\\s*: it will pick up the second two signal but and for the second one it picks up CS and pS and but the d and S in the next signal when i use matcher.group() come up seperately Can anyone give me an expression that will pick up all signal names whether there is one two three or more?

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• Query on MVVM pattern in WPF?

  - by Ashish Ashu

  I am implementing a MVVM pattern in my WPF application. My application main window is divided into four parts: Main Menu On the Top Outlook Navigation Control on the Left. A List View on the Middle. Another List view on the bottom. The Navigation control shows different setting (configuration) controls in the Tab items. All the four above are user controls which are placed in the main window. And corresponding to each user control there is separate view model which is bounded with a view model in the XAML of each control, however the model class remain the same between all the view model. And a MainWindow has a seperate View Model which is also bounded with a view model in the XAML of each control. Please help me out in framing a design in which each view models of all the controls above will interact with each other. Please let me know if my question is not clear to you!!

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• EF4, self tracking, repository pattern, SQL Server 2008 AND SQL Server Compact

  - by Darren

  Hi, I am creating a project using Entity Frameworks 4 and self tracking entities. I want to be able to either get the data from a sql server 2008 database or from sql server compact database (with the switch being in the config file). I am using the repository pattern and I will have the self tracking entities sitting in a separate assembly. Do I need two edmx files? If so, how do I generate only one set of STE's in the separate assembly? Also do I need to generate two context classes as well? I am unsure of the plumbing for all this. Can anyone help? Darren I forgot to add that the two databases will be identical and that the compact version is for offline usage.

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