/** @throws Exception If failed. */
  public void testClientAffinity() throws Exception {
    GridClientData partitioned = client.data(PARTITIONED_CACHE_NAME);

    Collection<Object> keys = new ArrayList<>();

    keys.addAll(Arrays.asList(Boolean.TRUE, Boolean.FALSE, 1, Integer.MAX_VALUE));

    Random rnd = new Random();
    StringBuilder sb = new StringBuilder();

    // Generate some random strings.
    for (int i = 0; i < 100; i++) {
      sb.setLength(0);

      for (int j = 0; j < 255; j++)
        // Only printable ASCII symbols for test.
        sb.append((char) (rnd.nextInt(0x7f - 0x20) + 0x20));

      keys.add(sb.toString());
    }

    // Generate some more keys to achieve better coverage.
    for (int i = 0; i < 100; i++) keys.add(UUID.randomUUID());

    for (Object key : keys) {
      UUID nodeId = grid(0).mapKeyToNode(PARTITIONED_CACHE_NAME, key).id();

      UUID clientNodeId = partitioned.affinity(key);

      assertEquals(
          "Invalid affinity mapping for REST response for key: " + key, nodeId, clientNodeId);
    }
  }
  /** {@inheritDoc} */
  @Override
  public Map<? extends GridComputeJob, GridNode> map(List<GridNode> subgrid, Integer arg)
      throws GridException {
    assert taskSes != null;
    assert arg != null;
    assert arg > 0;

    Map<GridSessionLoadTestJob, GridNode> map = new HashMap<>(subgrid.size());

    Iterator<GridNode> iter = subgrid.iterator();

    Random rnd = new Random();

    params = new HashMap<>(arg);

    Collection<UUID> assigned = new ArrayList<>(subgrid.size());

    for (int i = 0; i < arg; i++) {
      // Recycle iterator.
      if (!iter.hasNext()) iter = subgrid.iterator();

      String paramName = UUID.randomUUID().toString();

      int paramVal = rnd.nextInt();

      taskSes.setAttribute(paramName, paramVal);

      GridNode node = iter.next();

      assigned.add(node.id());

      map.put(new GridSessionLoadTestJob(paramName), node);

      params.put(paramName, paramVal);

      if (log.isDebugEnabled())
        log.debug("Set session attribute [name=" + paramName + ", value=" + paramVal + ']');
    }

    taskSes.setAttribute("nodes", assigned);

    return map;
  }