There's no possibility to change the location of the wsdl file. The wsdl attribute at sun-jaxws.xml must have the prefix "WEB-INF/wsdl". Else JAX-WS generates and publishes a new WSDL. If you take a look at the source code of jaxws-ri, you can find the implementation at the class com.sun.xml.ws.transport.http.DeploymentDescriptorParser, method getPrimaryWSDL:
...
if (wsdlFile != null) {
if (!wsdlFile.startsWith(JAXWS_WSDL_DD_DIR)) {
logger.log(Level.WARNING, "Ignoring wrong wsdl={0}. It should start with {1}. Going to generate and publish a new WSDL.", new Object[]{wsdlFile, JAXWS_WSDL_DD_DIR});
return null;
}
...
}