Richard Wilkinson’s Blog

Terracotta and Wicket (the next generation)

Edit: with the 1.1.3 release you should follow the instructions on this post.  It is no longer required for you to set up the page store yourself.

The new terracotta wicket-tim is out!

Any wicket and terracotta users will know that the previous wicket-tim had issues under heavy load, which is why some months ago I set about creating something better, with lots of help from the wicket community, especially Stefan Fussenegger, we created a new in-memory page map which can cope with high load.

To use this you will need to add the wicket-tim to your classpath, if you are using maven then add this to your pom.xml file:

	org.terracotta.modules
	tim-wicket
	1.1.1

And follow the installation instructions.

In your tc-config.xml you will need to include the wicket-tim module, you can find instructions on how to do this here and here.

Then in your wicket application class you need to use the new page map:

public ISessionStore newSessionStore() {
     return new SecondLevelCacheSessionStore(this,
       new TerracottaPageStore(100));
}

The 100 in the page store parameter is the number of pages (or versions of pages) of history to keep inthe page map, and can be set to anything you feel is appropriate.

The page map is stored in the httpsession so you will need to make sure that httpsession clustering is working correctly.  If you are using tomcat then terracotta should do this automatically.

Feedback and bug reports are welcome, particularity about the user configurable number of pages history.  If we remove this then it will be possible to use byte-code instrumentation to automatically add in the TerracottaPageStore, meaning that the wicket-tim wont need adding onto your application build path.

Richard

Next London Wicket Event

More Warped Wicket

Earlier this year I wrote a post on integrating wicket and warp persist, and I thought it was about time I posted an update, but this time I included working example projects.

The first project is a basic wicket / warp persist setup with hibernate and an apache derby database.  It allows you to persist the Event class used in the hibernate examples.

wicketwarp.zip

The second project is the same, but also makes use of warp-servlet for hooking up all your other servlets and filters in guicy way.

wicketwarpservlet.zip

In both cases i’ve tried to keep xml configuration down to a minimum, as I hate xml config.  So the hibernate classes are configured with hibernate annotations.  Wicket itself involves no xml configuration as always.

As warp persist and warp servlet are not in a maven repository (as far as I know) you will need to manually add them into your maven repository in the normal way.

Thoughts, Code patches, Comments, etc are welcome.