/** @throws Exception If failed. */
  @SuppressWarnings("unchecked")
  public void testCancel() throws Exception {
    Grid grid = G.grid(getTestGridName());

    grid.compute()
        .localDeployTask(GridCancelTestTask.class, U.detectClassLoader(GridCancelTestTask.class));

    GridComputeTaskFuture<?> fut = grid.compute().execute(GridCancelTestTask.class.getName(), null);

    // Wait until jobs begin execution.
    boolean await = startSignal.await(WAIT_TIME, TimeUnit.MILLISECONDS);

    assert await : "Jobs did not start.";

    info("Test task result: " + fut);

    assert fut != null;

    // Only first job should successfully complete.
    Object res = fut.get();
    assert (Integer) res == 1;

    // Wait for all jobs to finish.
    await = stopSignal.await(WAIT_TIME, TimeUnit.MILLISECONDS);
    assert await : "Jobs did not stop.";

    // One is definitely processed. But there might be some more processed or cancelled or processed
    // and cancelled.
    // Thus total number should be at least SPLIT_COUNT and at most (SPLIT_COUNT - 1) *2 +1
    assert (cancelCnt + processedCnt) >= SPLIT_COUNT
            && (cancelCnt + processedCnt) <= (SPLIT_COUNT - 1) * 2 + 1
        : "Invalid cancel count value: " + cancelCnt;
  }
    /**
     * Check if flags in correct state.
     *
     * @param msg Message.
     */
    private void checkSyncFlags(GridIoMessage msg) {
      if (!commSpiEnabled) return;

      Object o = msg.message();

      if (!(o instanceof GridDistributedLockRequest)) return;

      GridKernal g = (GridKernal) G.grid(nodeId);

      GridCacheTxManager<Object, Object> tm =
          g.internalCache(REPLICATED_ASYNC_CACHE_NAME).context().tm();

      GridCacheVersion v = ((GridCacheVersionable) o).version();

      GridCacheTxEx t = tm.tx(v);

      if (t.hasWriteKey("x1")) {
        assertFalse(t.syncCommit());
      } else if (t.hasWriteKey("x2")) {
        assertTrue(t.syncCommit());
      } else if (t.hasWriteKey("x3")) {
        assertFalse(t.syncCommit());
      } else if (t.hasWriteKey("x4")) {
        assertTrue(t.syncCommit());
      }
    }