how to use EL from java in a JSF 1.2 environment

There are not much examples, how to use a ELExpression from your java code. The most examples I found, are focussing on „implement your own ELResolver“. The best documentation comes from SUN in form of tutorials and package/javadoc.

Now I will provide some tips how to deal with EL expressions from java. I have tested and implemented this in a JSF 1.2 web application, where I have access to the FacesContext.

In JSF 1.2 you have access to expression factory:

// get application from faces context
Application app = FacesContext.getInstance().getApplication();
ExpressionFactory exprFactory = app.getExpressionFactory();

Now you can use the expression factory to get a MethodExpression or ValueExpression. In my projects we need very often ValueExpressions.

But first you need also an ELContext. There are many implementations available of such context (for JSP, Faces and so on) and enough documentation how to create your own context.
You can access such context again from the faces context:

// getting the ELContext from faces context
ELContext elContext = FacesContext.getInstance().getELContext();
// creating value expression with the help of the expression factory and the ELContext
ValueExpression valExpr = exprFactory.createValueExpression(elContext, "#{devBean.devMode}", Boolean.class);

In this example I will use the boolean value from a „devBean“ to work later with this value. Of course, you can inject the value expression, required class type and so on.
The last needed thing is to assign the value to a local variable:

Boolean developmentMode = (Boolean) valExpr.getValue(elContext);

Thats it!

updating mediawiki is easy

I have updated some homepages to the brand new mediawiki version 1.13.2 which was very easy. They have a very good description what you have to do, if you update to a new version and a very nice update script which works also for very old wiki versions (I have tested this with the 1.4.5 version).

But there ara small problems with own skin (for example on http://www.buzztard.org). The skin have to be fixed per hand. Hopfully ensonic can do this the next days.