1 | /** |
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2 | * Licensed to the Apache Software Foundation (ASF) under one |
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3 | * or more contributor license agreements. See the NOTICE file |
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4 | * distributed with this work for additional information |
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5 | * regarding copyright ownership. The ASF licenses this file |
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6 | * to you under the Apache License, Version 2.0 (the |
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7 | * "License"); you may not use this file except in compliance |
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8 | * with the License. You may obtain a copy of the License at |
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9 | * |
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10 | * http://www.apache.org/licenses/LICENSE-2.0 |
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11 | * |
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12 | * Unless required by applicable law or agreed to in writing, software |
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13 | * distributed under the License is distributed on an "AS IS" BASIS, |
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14 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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15 | * See the License for the specific language governing permissions and |
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16 | * limitations under the License. |
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17 | */ |
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18 | package org.apache.hadoop.mapred; |
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19 | |
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20 | import java.io.DataOutputStream; |
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21 | |
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22 | import junit.framework.TestCase; |
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23 | |
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24 | import org.apache.hadoop.fs.BlockLocation; |
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25 | import org.apache.hadoop.fs.FileStatus; |
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26 | import org.apache.hadoop.fs.FileSystem; |
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27 | import org.apache.hadoop.fs.Path; |
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28 | import org.apache.hadoop.hdfs.MiniDFSCluster; |
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29 | |
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30 | public class TestFileInputFormat extends TestCase { |
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31 | |
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32 | public void testLocality() throws Exception { |
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33 | JobConf conf = new JobConf(); |
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34 | MiniDFSCluster dfs = null; |
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35 | try { |
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36 | dfs = new MiniDFSCluster(conf, 4, true, |
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37 | new String[]{"/rack0", "/rack0", |
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38 | "/rack1", "/rack1"}, |
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39 | new String[]{"host0", "host1", |
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40 | "host2", "host3"}); |
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41 | FileSystem fs = dfs.getFileSystem(); |
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42 | System.out.println("FileSystem " + fs.getUri()); |
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43 | Path path = new Path("/foo/bar"); |
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44 | // create a multi-block file on hdfs |
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45 | DataOutputStream out = fs.create(path, true, 4096, |
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46 | (short) 2, 512, null); |
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47 | for(int i=0; i < 1000; ++i) { |
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48 | out.writeChars("Hello\n"); |
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49 | } |
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50 | out.close(); |
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51 | System.out.println("Wrote file"); |
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52 | |
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53 | // split it using a file input format |
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54 | TextInputFormat.addInputPath(conf, path); |
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55 | TextInputFormat inFormat = new TextInputFormat(); |
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56 | inFormat.configure(conf); |
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57 | InputSplit[] splits = inFormat.getSplits(conf, 1); |
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58 | FileStatus fileStatus = fs.getFileStatus(path); |
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59 | BlockLocation[] locations = |
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60 | fs.getFileBlockLocations(fileStatus, 0, fileStatus.getLen()); |
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61 | System.out.println("Made splits"); |
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62 | |
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63 | // make sure that each split is a block and the locations match |
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64 | for(int i=0; i < splits.length; ++i) { |
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65 | FileSplit fileSplit = (FileSplit) splits[i]; |
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66 | System.out.println("File split: " + fileSplit); |
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67 | for (String h: fileSplit.getLocations()) { |
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68 | System.out.println("Location: " + h); |
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69 | } |
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70 | System.out.println("Block: " + locations[i]); |
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71 | assertEquals(locations[i].getOffset(), fileSplit.getStart()); |
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72 | assertEquals(locations[i].getLength(), fileSplit.getLength()); |
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73 | String[] blockLocs = locations[i].getHosts(); |
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74 | String[] splitLocs = fileSplit.getLocations(); |
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75 | assertEquals(2, blockLocs.length); |
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76 | assertEquals(2, splitLocs.length); |
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77 | assertTrue((blockLocs[0].equals(splitLocs[0]) && |
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78 | blockLocs[1].equals(splitLocs[1])) || |
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79 | (blockLocs[1].equals(splitLocs[0]) && |
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80 | blockLocs[0].equals(splitLocs[1]))); |
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81 | } |
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82 | } finally { |
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83 | if (dfs != null) { |
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84 | dfs.shutdown(); |
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85 | } |
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86 | } |
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87 | } |
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88 | |
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89 | } |
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