Asynchronous resources

The following example shows a simple asynchronous resource method using the new JAX-RS async features:

@GET
@Path("/simple")
public void asyncGet(@Suspended final AsyncResponse asyncResponse) {
   new Thread(new Runnable() {
      @Override
      public void run() {
       String result = veryExpensiveOperation();
         asyncResponse.resume(result);
      }
   private String veryExpensiveOperation() {
    return new MagicNumber(3) + "";
   }
  }).start();
}

We have a JAX-RS AsyncResponse class passed as an attribute to a GET method implementation, asyncGet. This method injects an instance of AsyncResponse using the javax.ws.rs.container.Suspended annotation.

This annotation is very similar to the javax.ws.rs.core.Context annotation. The @Context annotation allows us to inject a REST response. The @Suspend annotation does the same with the difference...