コード例 #1
0
  /**
   * Listen to events that happen only on local node.
   *
   * @throws IgniteException If failed.
   */
  private static void localListen() throws IgniteException {
    System.out.println();
    System.out.println(">>> Local event listener example.");

    Ignite ignite = Ignition.ignite();

    IgnitePredicate<TaskEvent> lsnr =
        evt -> {
          System.out.println(
              "Received task event [evt=" + evt.name() + ", taskName=" + evt.taskName() + ']');

          return true; // Return true to continue listening.
        };

    // Register event listener for all local task execution events.
    ignite.events().localListen(lsnr, EVTS_TASK_EXECUTION);

    // Generate task events.
    ignite
        .compute()
        .withName("example-event-task")
        .run(() -> System.out.println("Executing sample job."));

    // Unsubscribe local task event listener.
    ignite.events().stopLocalListen(lsnr);
  }
コード例 #2
0
  /**
   * Listen to events coming from all cluster nodes.
   *
   * @throws IgniteException If failed.
   */
  private static void remoteListen() throws IgniteException {
    System.out.println();
    System.out.println(">>> Remote event listener example.");

    // This optional local callback is called for each event notification
    // that passed remote predicate listener.
    IgniteBiPredicate<UUID, TaskEvent> locLsnr =
        (nodeId, evt) -> {
          // Remote filter only accepts tasks whose name being with "good-task" prefix.
          assert evt.taskName().startsWith("good-task");

          System.out.println(
              "Received task event [evt=" + evt.name() + ", taskName=" + evt.taskName());

          return true; // Return true to continue listening.
        };

    // Remote filter which only accepts tasks whose name begins with "good-task" prefix.
    IgnitePredicate<TaskEvent> rmtLsnr = evt -> evt.taskName().startsWith("good-task");

    Ignite ignite = Ignition.ignite();

    // Register event listeners on all nodes to listen for task events.
    ignite.events().remoteListen(locLsnr, rmtLsnr, EVTS_TASK_EXECUTION);

    // Generate task events.
    for (int i = 0; i < 10; i++) {
      ignite
          .compute()
          .withName(i < 5 ? "good-task-" + i : "bad-task-" + i)
          .run(
              new IgniteRunnable() {
                // Auto-inject task session.
                @TaskSessionResource private ComputeTaskSession ses;

                @Override
                public void run() {
                  System.out.println("Executing sample job for task: " + ses.getTaskName());
                }
              });
    }
  }