code: public Schema compileSchema( InputStream stream )
  		throws VerifierConfigurationException, SAXException, IOException {
  		
  		return compileSchema(stream,null);
  	}
docs: processes a schema into a Schema object, which is a compiled representation
  of a schema.
  
  The obtained schema object can then be used concurrently across multiple
  threads.
  
  @param	stream
  A stream object that holds a schema.