/**
   * Validates that the parent parameter was acceptable.
   *
   * @return True if the parent parameter is valid for the current container.
   */
  private boolean validateParent(GadgetContext context) {
    String container = context.getContainer();
    String parent = context.getParameter("parent");

    if (parent == null) {
      // If there is no parent parameter, we are still safe because no
      // dependent code ever has to trust it anyway.
      return true;
    }

    List<Object> parents = containerConfig.getList(container, "gadgets.parent");
    if (parents.isEmpty()) {
      // Allow all.
      return true;
    }

    // We need to check each possible parent parameter against this regex.
    for (Object pattern : parents) {
      if (Pattern.matches(pattern.toString(), parent)) {
        return true;
      }
    }

    return false;
  }
 @Before
 public void setUp() {
   LinkedList<String> containers = new LinkedList<String>();
   containers.add("default");
   config = createMock(ContainerConfig.class);
   expect(config.getContainers()).andReturn(containers);
   replay(config);
   crypter = createMock(BlobCrypter.class);
 }