/** ends a block in which nested nodes are created.
* This method requires that a nested node block was started before
* with {@link #compositeNode(String)} */
public ProcessFactory compositeEnd() {
if (exceptionHandler!=null) {
throw new PvmException("exceptionHandler needs to be closed with exceptionHandlerEnd");
}
if (compositeElementStack==null) {
throw new PvmException("no composite node was started");
}
compositeElement = compositeElementStack.pop();
if (compositeElementStack.isEmpty()) {