code: @Override
      public DescribeWorkspaceDirectoriesResult describeWorkspaceDirectories(DescribeWorkspaceDirectoriesRequest request) {
          request = beforeClientExecution(request);
          return executeDescribeWorkspaceDirectories(request);
      }
docs: <p>
  Describes the available AWS Directory Service directories that are registered with Amazon WorkSpaces.
  </p>
  
  @param describeWorkspaceDirectoriesRequest
  @return Result of the DescribeWorkspaceDirectories operation returned by the service.
  @throws InvalidParameterValuesException
  One or more parameter values are not valid.
  @sample AmazonWorkspaces.DescribeWorkspaceDirectories
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/workspaces-2015-04-08/DescribeWorkspaceDirectories"
  target="_top">AWS API Documentation</a>