//NOTE we use the EntityhubConfiguration to have the same pre-registered
// namespaces as the other components.
this.backend = (RDFBackend)indexingSource;
this.configuration = new EntityhubConfiguration(vf);
this.transformer = configuration.getTransformers();
this.ldPath = new LDPath(backend,configuration);
} else {
throw new IllegalArgumentException("The configured IndexingSource '"
+ indexingSource.getClass().getSimpleName()+"' does not support "
+ "LDPath (does not implement RDFBackend)! This Processor "
+ "can only be used with IndexingSources that support LDPath!");