callbackMethod.addParameter(asyncHandler);
JAnnotation asyncHandlerAnnotation = new JAnnotation(WebParam.class);
asyncHandlerAnnotation.addElement(new JAnnotationElement("name", "asyncHandler"));
asyncHandlerAnnotation.addElement(new JAnnotationElement("targetNamespace", ""));
asyncHandler.addAnnotation("WebParam", asyncHandlerAnnotation);
method.getInterface().addImport("javax.jws.WebParam");
method.getInterface().addMethod(callbackMethod);
}