001/*
002 * Copyright (c) 2007-2015 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;
022
023import java.io.IOException;
024
025/**
026 * Class FlowSkipIfSinkExists is a {@link cascading.flow.FlowSkipStrategy} implementation that returns
027 * {@code true} if the Flow sink exists, regardless if it is stale or not.
028 */
029public class FlowSkipIfSinkExists implements FlowSkipStrategy
030  {
031  public boolean skipFlow( Flow flow ) throws IOException
032    {
033    // if tap is in replace mode, will be treated as not existing
034    long sinkModified = flow.getSinkModified();
035
036    if( sinkModified <= 0 ) // do not skip, sinks don't exist
037      return false;
038
039    return true;
040    }
041  }