java web service using post method

I did a java rest web service using GET method.The web service works fine with GET method.But when i try it with POST method it doesn't display anything. Below is my simple code to test it with POST method. Please anyone help me in solving this issue.

package wsRevDash;

@Path("/post")
public class Testpost {


    @POST
    @Path("/test")
    public String POST(@QueryParam("param") String msg) {
        String output = "POST:hELLO: "+msg;
        return output;
 }

}