RESTful webservice : how to set headers in java to accept XMLHttpRequest allowed by Access-Control-Allow-Origin

Read here about your issue CORS : http://enable-cors.org/

Check if this one help you in your getMsg() method:
return Response.ok(output).header("Access-Control-Allow-Origin", "*").build();

If above doesn’t work try to add Jersey filter to your service. Create filter class:

package your.package;

public class CORSFilter implements ContainerResponseFilter {

    @Override
    public ContainerResponse filter(ContainerRequest creq, ContainerResponse cresp) {

        cresp.getHttpHeaders().putSingle("Access-Control-Allow-Origin", "*");
        cresp.getHttpHeaders().putSingle("Access-Control-Allow-Credentials", "true");
        cresp.getHttpHeaders().putSingle("Access-Control-Allow-Methods", "GET, POST, DELETE, PUT, OPTIONS, HEAD");
        cresp.getHttpHeaders().putSingle("Access-Control-Allow-Headers", "Content-Type, Accept, X-Requested-With");

        return cresp;
    }
}

And register later win web.xml with:

<servlet>
<servlet-name>CORS Filter</servlet-name>
<servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
 <init-param>
    <param-name>com.sun.jersey.spi.container.ContainerResponseFilters</param-name>
    <param-value>your.package.CORSFilter</param-value>
 </init-param>
</servlet>
<servlet-mapping>
    <servlet-name>CORS Filter</servlet-name>
    <url-pattern>/webservices/*</url-pattern>
</servlet-mapping>

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Another solution is to use this code inside your resource to provide OPTIONS for the browser. Put this in the class where you have @GET.

  @OPTIONS
  @Path("/getsample")
  public Response getOptions() {
    return Response.ok()
      .header("Access-Control-Allow-Origin", "*")
      .header("Access-Control-Allow-Methods", "POST, GET, PUT, UPDATE, OPTIONS")
      .header("Access-Control-Allow-Headers", "Content-Type, Accept, X-Requested-With").build();
  }

---

If non of this work, try to exchange the "*" provided for “Access-Control-Allow-Origin” header with your custom domain where you access this resource. I.g. If you call this from http://localhost::8080 use something like this ("Access-Control-Allow-Origin", "http://localhost:8080") instead of asterisk "*".