View difference between Paste ID: 1tBbTP1j and eevJTshS

 // Controller
 public String execute()
 throws Exception {
   if(UserSecurityContext.hasPermission("SOME_AUTHORIZATION")) {
     try {
-      service.callSomething();
+      ServiceResult result = service.callSomething();
-      return SUCCESS;
+      return result.execute(this);
     }
     catch(SomeReallyBadUnExpectedException e) {
       e.printStackTrace();
       throw new RuntimeException(e);
     }
   }
   else {
     addActionError("error.permission.denied");
     return INPUT;
   }
 }
 
 public class AccessDeniedServiceResult implements ServiceResult {
   @Override
   public String execute(Action action) {
     action.addActionError("error.permission.denied");
     return INPUT;
   }
 }
 
 // Service
 // Just an example of how you can do service exceptions
 public ServiceResult callSomething()
 throws AccessDeniedException {
   if(!UserSecurityContext.hasPermission("SOME_AUTH"))
     return new AccessDeniedServiceResult();
 
   // do your service stuff
 }