OpenSAML user discussion

Hello,

I am currently trying to implement opensaml2 in a project.
I get some problems with all the builders.
For example, with this code :


XMLObjectBuilderFactory builderFactory = Configuration.getBuilderFactory();

AssertionBuilder asserBuild = (AssertionBuilder) 
builderFactory.getBuilder(Assertion.DEFAULT_ELEMENT_NAME);

Assertion saml2Assertion = asserBuild.buildObject();


I get a java.lang.NullPointerException, and when I check the value of 
asserBuild it gives me null.
I get this problem with all the builders (subject, issuer...).

I saw someone who got the same problem here with an issuerBuilder, but didn't 
find any solution from that. It seems that the libraries are correctly 
installed and Eclipe doesn't tell me that there is a problem in the code.

If anyone has a solution...
Thank you in advance.

Julien Noizet