tell wsdl2java not to generate code if file is not modified since last code was generated

basically i am using ant to generate webservice client and server stubs. We don't change wsdl as frequently as our java code. But since wsdl2java generated code is always new, javac target always compiles code (too slow). Is there a wa开发者_运维技巧y to tell wsdl2java task that gensrc is not modified so don't generate code ?

You should excecute wsdl2java task only if the wsdl was modified. How to execute an Ant task only when wsdl files have been modified?