    001/*
    002 * Copyright (c) 2007-2016 Concurrent, Inc. All Rights Reserved.
    003 *
    004 * Project and contact information: http://www.cascading.org/
    005 *
    006 * This file is part of the Cascading project.
    007 *
    008 * Licensed under the Apache License, Version 2.0 (the "License");
    009 * you may not use this file except in compliance with the License.
    010 * You may obtain a copy of the License at
    011 *
    012 *     http://www.apache.org/licenses/LICENSE-2.0
    013 *
    014 * Unless required by applicable law or agreed to in writing, software
    015 * distributed under the License is distributed on an "AS IS" BASIS,
    016 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    017 * See the License for the specific language governing permissions and
    018 * limitations under the License.
    019 */
    020
    021package cascading.flow.planner.rule.expression;
    022
    023import cascading.flow.planner.iso.expression.ElementCapture;
    024import cascading.flow.planner.iso.expression.ExpressionGraph;
    025import cascading.flow.planner.iso.expression.FlowElementExpression;
    026import cascading.flow.planner.iso.expression.OperationExpression;
    027import cascading.flow.planner.rule.RuleExpression;
    028import cascading.operation.GroupAssertion;
    029import cascading.pipe.Every;
    030import cascading.pipe.Group;
    031
    032import static cascading.flow.planner.iso.expression.NotElementExpression.not;
    033
    034/**
    035 *
    036 */
    037public class LoneGroupExpression extends RuleExpression
    038  {
    039  public LoneGroupExpression()
    040    {
    041    super(
    042      new ExpressionGraph()
    043        .arcs(
    044          new FlowElementExpression( Group.class ),
    045          new OperationExpression( ElementCapture.Primary, GroupAssertion.class ),
    046          not( new FlowElementExpression( Every.class ) )
    047        )
    048    );
    049    }
    050  }