If you are using Jersey for REST API's you can do as below
You don't have to change your webservices implementation.
I will explain for Jersey 2.x
1) First add a ResponseFilter as shown below
import java.io.IOException;
import javax.ws.rs.container.ContainerRequestContext;
import javax.ws.rs.container.ContainerResponseContext;
import javax.ws.rs.container.ContainerResponseFilter;
public class CorsResponseFilter implements ContainerResponseFilter {
@Override
public void filter(ContainerRequestContext requestContext, ContainerResponseContext responseContext)
throws IOException {
responseContext.getHeaders().add("Access-Control-Allow-Origin","*");
responseContext.getHeaders().add("Access-Control-Allow-Methods", "GET, POST, DELETE, PUT");
}
}
2) then in the web.xml , in the jersey servlet declaration add the below
<init-param>
<param-name>jersey.config.server.provider.classnames</param-name>
<param-value>YOUR PACKAGE.CorsResponseFilter</param-value>
</init-param>