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.hadoop; 022 023 import java.beans.ConstructorProperties; 024 import java.io.IOException; 025 026 import cascading.scheme.Scheme; 027 import cascading.tap.SinkMode; 028 import cascading.tap.TapException; 029 import cascading.tuple.Fields; 030 import org.apache.hadoop.fs.FileSystem; 031 import org.apache.hadoop.mapred.JobConf; 032 033 /** 034 * Class Lfs is a {@link cascading.tap.Tap} class that provides access to the Local File System via Hadoop. 035 * <p/> 036 * Note that using a Lfs {@link cascading.tap.Tap} instance in a {@link cascading.flow.Flow} will force a portion of not the whole Flow to be executed 037 * in "local" mode forcing the Flow to execute in the current JVM. Mixing with {@link cascading.tap.hadoop.Dfs} and other Tap 038 * types is possible, providing a means to implement complex file/data management functions. 039 * <p/> 040 * Use {@link cascading.tap.hadoop.Hfs} if you need a Tap instance that inherits the default {@link FileSystem} used by Hadoop. 041 */ 042 public class Lfs extends Hfs 043 { 044 @ConstructorProperties({"scheme"}) 045 Lfs( Scheme scheme ) 046 { 047 super( scheme ); 048 } 049 050 /** 051 * Constructor Lfs creates a new Lfs instance. 052 * 053 * @param fields of type Fields 054 * @param stringPath of type String 055 */ 056 @ConstructorProperties({"fields", "stringPath"}) 057 @Deprecated 058 public Lfs( Fields fields, String stringPath ) 059 { 060 super( fields, stringPath ); 061 } 062 063 /** 064 * Constructor Lfs creates a new Lfs instance. 065 * 066 * @param scheme of type Scheme 067 * @param stringPath of type String 068 */ 069 @ConstructorProperties({"scheme", "stringPath"}) 070 public Lfs( Scheme scheme, String stringPath ) 071 { 072 super( scheme, stringPath ); 073 } 074 075 /** 076 * Constructor Lfs creates a new Lfs instance. 077 * 078 * @param scheme of type Scheme 079 * @param stringPath of type String 080 * @param replace of type boolean 081 */ 082 @ConstructorProperties({"scheme", "stringPath", "replace"}) 083 @Deprecated 084 public Lfs( Scheme scheme, String stringPath, boolean replace ) 085 { 086 super( scheme, stringPath, replace ); 087 } 088 089 /** 090 * Constructor Lfs creates a new Lfs instance. 091 * 092 * @param fields of type Fields 093 * @param stringPath of type String 094 * @param sinkMode of type SinkMode 095 */ 096 @ConstructorProperties({"fields", "stringPath", "sinkMode"}) 097 @Deprecated 098 public Lfs( Fields fields, String stringPath, SinkMode sinkMode ) 099 { 100 super( fields, stringPath, sinkMode ); 101 } 102 103 /** 104 * Constructor Lfs creates a new Lfs instance. 105 * 106 * @param scheme of type Scheme 107 * @param stringPath of type String 108 * @param sinkMode of type SinkMode 109 */ 110 @ConstructorProperties({"scheme", "stringPath", "sinkMode"}) 111 public Lfs( Scheme scheme, String stringPath, SinkMode sinkMode ) 112 { 113 super( scheme, stringPath, sinkMode ); 114 } 115 116 protected void setStringPath( String stringPath ) 117 { 118 if( stringPath.matches( ".*://.*" ) && !stringPath.startsWith( "file://" ) ) 119 throw new IllegalArgumentException( "uri must use the file scheme" ); 120 121 super.setStringPath( stringPath ); 122 } 123 124 protected FileSystem getFileSystem( JobConf conf ) 125 { 126 try 127 { 128 return FileSystem.getLocal( conf ); 129 } 130 catch( IOException exception ) 131 { 132 throw new TapException( "unable to get handle to get local filesystem", exception ); 133 } 134 } 135 }