[Maven-plugins-developer] Classloader problem with Maven 2.0.4, Xalan 2.8.1, Xerces 2.8.0 and Java 1.5

[Aaron D. <Aar...@gl...>]

Hello,

I'm trying to port StatCVS to maven2 and had some success ... well, if I invoke
StatCVS as a subprocess.

Now, I'm stuck while invoking StatCVS from Java. When I try, I get this error:

saxFactory=org.apache.xerces.jaxp.SAXParserFactoryImpl
java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
...
Caused by: javax.xml.parsers.FactoryConfigurationError: Provider org.apache.xerc
es.jaxp.SAXParserFactoryImpl could not be instantiated: java.lang.NullPointerExc
eption
        at javax.xml.parsers.SAXParserFactory.newInstance(Unknown Source)
        at de.berlios.statcvs.xml.output.HTMLRenderer.create(HTMLRenderer.java:98)

Ok, what happens is this:

    SAXParserFactory x = new org.apache.xerces.jaxp.SAXParserFactoryImpl();
    System.out.println("saxFactory="+x.getClass().getName());
            
    x = SAXParserFactory.newInstance(); // <-- This is line 98
    System.out.println("saxFactory="+x.getClass().getName());

So basically, when I instantiate the SAXParserFactoryImpl directly, it works
which means that Xerces is in the classpath. When I use
javax.xml.parsers.SAXParserFactory.newInstance() (as I should), I get a NPE but
the classname is the same in both cases!

When I run this code within Eclipse, it works. Therefore, I assume that maven
somehow breaks this but I have no idea what could cause this.

Any ideas?

Best Regards,

-- 
Aaron Digulla