Categories
Coding

Log4j XML Configuration

For some reason, I can’t seem to retain a key piece of information – how to configure the logging level per-package in the log4j XML configuration. I’m putting this snippet here to cater for the likely event that I’ll forget it again. It’s all to do with the category element, as it happens. 

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">

<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">

  <appender name="ConsoleAppender" class="org.apache.log4j.ConsoleAppender">
    <layout class="org.apache.log4j.SimpleLayout"/>
  </appender>

  <category name="org.apache">
        <priority value="warn"/>
  </category>

  <root>
    <priority value="debug" />
    <appender-ref ref="ConsoleAppender"/>
  </root>

</log4j:configuration>
Categories
Coding

Spring, Hibernate and LazyInitializationExceptions

I’ve recently started using Spring for its comprehensive support for Hibernate 3. It makes writing DAOs a snap. There are a couple of wrinkles, however, one is the fact that lazy loading in Hibernate 3 is the default, combined with the fact that Spring will close the Hibernate Session automatically, giving you a LazyInitializationException when you try to access mapped fields from your persistent objects. The solution to this is the “Open Session In View” pattern, which Spring provide a ready-made filter for. Shown below is an extract from my PersistentTestCase, superclass, which all my DAO tests extend, and voila, no more Lazy Exceptions.



protected void setUp() throws ClassNotFoundException, SQLException {
      ClassPathXmlApplicationContext appContext = new ClassPathXmlApplicationContext("application_context.xml");
      factory = (BeanFactory) appContext;
      
      sessionFactory = (SessionFactory)factory.getBean("test.sessionFactory");
      Session s = sessionFactory.openSession();
      TransactionSynchronizationManager.bindResource(sessionFactory, new SessionHolder(s));  
  }
  
  protected void tearDown() {
     SessionHolder sessionHolder = (SessionHolder) TransactionSynchronizationManager.unbindResource(sessionFactory);
     SessionFactoryUtils.closeSessionIfNecessary(sessionHolder.getSession(), sessionFactory); 
  }
Categories
Coding

Some Subversion Annoyances

A few things really bug me about Subversion. Overall, I like it, and will continue to use it, but there have been a few casualties along the way from the CVS-to-Subversion migration:

  • CVSGraph doesn/t work anymore. I know TSVN has a built-in revision viewer, but a) the graphs aren’t as nice, and b) have you ever tried it on a tree with a large number of revisions? Good luck!
  • The Eclipse CVS plugin. Now, I know that you can download SubClipse, but it’s extra effort, and it’s not as mature, or stable, as the built-in CVS equivalent. Plus, you need to download extra dependencies to get it to work.
  • Those nice StatCVS reports won’t work any more, either. Which I found out when a maven:site command bombed out 75% of the way through.

I know these are relatively small issues, and I’m sure they will be resolved in time, but they are annoying.