001    /*
002     * Copyright (c) 2007-2014 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    
021    package cascading.tap;
022    
023    import java.util.Iterator;
024    
025    /**
026     * Interface CompositeTap marks {@link Tap} classes as having child Tap instances.
027     * <p/>
028     * This information is required by the planner in order to properly configure the underlying platform.
029     */
030    public interface CompositeTap<Child extends Tap>
031      {
032      Iterator<Child> getChildTaps();
033    
034      long getNumChildTaps();
035      }