Changes between Initial Version and Version 1 of waue/2010/0201

Timestamp:

Feb 1, 2010, 2:54:25 PM (14 years ago)

Author:

waue

Comment:

--

waue/2010/0201

@@ +1 @@
+{{{
+#!html
+<div style="text-align: center; color:#151B8D"><big style="font-weight: bold;"><big><big>
+HBase 程式設計 
+</big></big></big></div> <div style="text-align: center; color:#7E2217"><big style="font-weight: bold;"><big>
+TableMapper 使用方式
+</big></big></div>
+}}}
+[[PageOutline]]
+
+ = example 1 = 
+
+{{{
+#!java
+public static void main(String[] args) throws Exception {
+Job myJob = new Job();
+myJob.setJobName("myJob");
+myJob.setJarByClass(MyClass.class);
+
+myJob.setMapOutputKeyClass(Text.class);
+myJob.setMapOutputValueClass(Text.class);
+
+myJob.setOutputKeyClass(Text.class);
+myJob.setOutputValueClass(Put.class);
+
+Scan myScan = new Scan("".getBytes(),"12345".getBytes());
+myScan.addColumn("Resume:Text".getBytes());
+
+TableMapReduceUtil.initTableMapperJob("inputTable", myScan, Map.class, Text.class, Text.class, myJob);
+TableMapReduceUtil.initTableReducerJob("outputTable", Reduce.class, myJob);
+
+myJob.setMapperClass(Map.class);
+myJob.setReducerClass(Reduce.class);
+
+myJob.setInputFormatClass(TableInputFormat.class);
+myJob.setOutputFormatClass(TableOutputFormat.class);
+
+myJob.setNumReduceTasks(12);
+
+myJob.submit();
+
+while(!myJob.isComplete()) {
+Thread.currentThread().sleep(10000);
+System.out.println("Map: " + (myJob.mapProgress() * 100) + "% ... Reduce: " + (myJob.reduceProgress() *
+100) + "%");
+}
+
+if(myJob.isSuccessful()) {
+System.out.println("Job Successful.");
+} else {
+System.out.println("Job Failed.");
+}
+}
+
+public static class Map extends TableMapper<Text,Text> {
+  public void map(ImmutableBytesWritable key, Result value, Mapper.Context context) throws
+IOException, InterruptedException {
+  }
+}
+
+public static class Reduce extends TableReducer<Writable,Writable,Put> {
+  public void reduce(Text key, Iterable<Text> values, Reducer.Context context) throws IOException,
+InterruptedException {
+  }
+}
+
+}}}
+
+
+ = Example 2 = 
+
+{{{
+#!java
+    public void map(ImmutableBytesWritable row, Result value,
+      Context context)
+    throws IOException {
+      try {
+        context.write(row, resultToPut(row, value));
+      } catch (InterruptedException e) {
+        e.printStackTrace();
+      }
+    }
+}}}
+
+ == 完整 == 
+
+{{{
+#!java
+/**
+ * Copyright 2009 The Apache Software Foundation
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.hbase.mapreduce;
+
+import java.io.IOException;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hbase.HBaseConfiguration;
+import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.client.Put;
+import org.apache.hadoop.hbase.client.Result;
+import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
+import org.apache.hadoop.mapreduce.Job;
+import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
+import org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFormat;
+import org.apache.hadoop.util.GenericOptionsParser;
+
+/**
+ * Import data written by {@link Export}.
+ */
+public class Import {
+  final static String NAME = "import";
+
+  /**
+   * Write table content out to files in hdfs.
+   */
+  static class Importer
+  extends TableMapper<ImmutableBytesWritable, Put> {
+    /**
+     * @param row  The current table row key.
+     * @param value  The columns.
+     * @param context  The current context.
+     * @throws IOException When something is broken with the data.
+     * @see org.apache.hadoop.mapreduce.Mapper#map(KEYIN, VALUEIN, 
+     *   org.apache.hadoop.mapreduce.Mapper.Context)
+     */
+    @Override
+    public void map(ImmutableBytesWritable row, Result value,
+      Context context)
+    throws IOException {
+      try {
+        context.write(row, resultToPut(row, value));
+      } catch (InterruptedException e) {
+        e.printStackTrace();
+      }
+    }
+
+    private static Put resultToPut(ImmutableBytesWritable key, Result result) 
+    throws IOException {
+      Put put = new Put(key.get());
+      for (KeyValue kv : result.raw()) {
+        put.add(kv);
+      }
+      return put;
+    }
+  }
+
+  /**
+   * Sets up the actual job.
+   * 
+   * @param conf  The current configuration.
+   * @param args  The command line parameters.
+   * @return The newly created job.
+   * @throws IOException When setting up the job fails.
+   */
+  public static Job createSubmittableJob(Configuration conf, String[] args) 
+  throws IOException {
+    String tableName = args[0];
+    Path inputDir = new Path(args[1]);
+    Job job = new Job(conf, NAME + "_" + tableName);
+    job.setJarByClass(Importer.class);
+    FileInputFormat.setInputPaths(job, inputDir);
+    job.setInputFormatClass(SequenceFileInputFormat.class);
+    job.setMapperClass(Importer.class);
+    // No reducers.  Just write straight to table.  Call initTableReducerJob
+    // because it sets up the TableOutputFormat.
+    TableMapReduceUtil.initTableReducerJob(tableName, null, job);
+    job.setNumReduceTasks(0);
+    return job;
+  }
+
+  /*
+   * @param errorMsg Error message.  Can be null.
+   */
+  private static void usage(final String errorMsg) {
+    if (errorMsg != null && errorMsg.length() > 0) {
+      System.err.println("ERROR: " + errorMsg);
+    }
+    System.err.println("Usage: Import <tablename> <inputdir>");
+  }
+
+  /**
+   * Main entry point.
+   * 
+   * @param args  The command line parameters.
+   * @throws Exception When running the job fails.
+   */
+  public static void main(String[] args) throws Exception {
+    HBaseConfiguration conf = new HBaseConfiguration();
+    String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();
+    if (otherArgs.length < 2) {
+      usage("Wrong number of arguments: " + otherArgs.length);
+      System.exit(-1);
+    }
+    Job job = createSubmittableJob(conf, otherArgs);
+    System.exit(job.waitForCompletion(true) ? 0 : 1);
+  }
+}
+}}}
+
+ = Example 3 = 
+ 
+{{{
+#!java
+  public static class ComputeSimilarity extends
+      TableMapper<ImmutableBytesWritable, Put> implements Configurable {
+    private Configuration conf = null;
+    private DenseMatrix matrix;
+
+    public void map(ImmutableBytesWritable key, Result value, Context context)
+        throws IOException, InterruptedException {
+      DenseVector v = new DenseVector(value);
+
+      Put put = new Put(key.get());
+      for (int i = 0; i < matrix.getRows(); i++) {
+        double dotProduct = matrix.getRow(i).dot(v);
+        if (BytesUtil.getRowIndex(key.get()) == i) {
+          dotProduct = 0;
+        }
+        put.add(Constants.COLUMNFAMILY, Bytes.toBytes(String
+            .valueOf(i)), Bytes.toBytes(dotProduct));
+      }
+
+      context.write(key, put);
+    }
+}}}
+
+ == 完整 ==
+{{{
+#!java
+import java.io.IOException;
+import java.io.UnsupportedEncodingException;
+
+import org.apache.hadoop.conf.Configurable;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.client.Put;
+import org.apache.hadoop.hbase.client.Result;
+import org.apache.hadoop.hbase.client.Scan;
+import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
+import org.apache.hadoop.hbase.mapreduce.IdentityTableReducer;
+import org.apache.hadoop.hbase.mapreduce.TableMapReduceUtil;
+import org.apache.hadoop.hbase.mapreduce.TableMapper;
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.mapreduce.Job;
+import org.apache.hama.Constants;
+import org.apache.hama.HamaCluster;
+import org.apache.hama.HamaConfiguration;
+import org.apache.hama.matrix.DenseMatrix;
+import org.apache.hama.matrix.DenseVector;
+import org.apache.hama.matrix.Matrix;
+import org.apache.hama.matrix.Vector;
+import org.apache.hama.util.BytesUtil;
+import org.apache.log4j.Logger;
+
+public class TestCosineSimilarityMatrix extends HamaCluster {
+  static final Logger LOG = Logger.getLogger(TestCosineSimilarityMatrix.class);
+  private int SIZE = 10;
+  private Matrix m1;
+  private Matrix symmetricMatrix;
+  private HamaConfiguration conf;
+
+  /**
+   * @throws UnsupportedEncodingException
+   */
+  public TestCosineSimilarityMatrix() throws UnsupportedEncodingException {
+    super();
+  }
+
+  public void setUp() throws Exception {
+    super.setUp();
+
+    conf = getConf();
+
+    m1 = DenseMatrix.random(conf, SIZE, SIZE);
+    symmetricMatrix = new DenseMatrix(conf, SIZE, SIZE);
+  }
+
+  public void testCosineSimilarity() throws IOException {
+    Job job = new Job(conf, "set MR job test");
+    job.getConfiguration().set("input.matrix", m1.getPath());
+
+    Scan scan = new Scan();
+    scan.addFamily(Constants.COLUMNFAMILY);
+
+    TableMapReduceUtil.initTableMapperJob(m1.getPath(), scan,
+        ComputeSimilarity.class, ImmutableBytesWritable.class, Put.class, job);
+    TableMapReduceUtil.initTableReducerJob(symmetricMatrix.getPath(),
+        IdentityTableReducer.class, job);
+    job.setNumReduceTasks(0);
+    try {
+      job.waitForCompletion(true);
+    } catch (InterruptedException e) {
+      e.printStackTrace();
+    } catch (ClassNotFoundException e) {
+      e.printStackTrace();
+    }
+
+    Vector v1 = m1.getRow(0);
+    Vector v2 = m1.getRow(2);
+    assertEquals(v1.dot(v2), symmetricMatrix.get(0, 2));
+  }
+
+  public static class ComputeSimilarity extends
+      TableMapper<ImmutableBytesWritable, Put> implements Configurable {
+    private Configuration conf = null;
+    private DenseMatrix matrix;
+
+    public void map(ImmutableBytesWritable key, Result value, Context context)
+        throws IOException, InterruptedException {
+      DenseVector v = new DenseVector(value);
+
+      Put put = new Put(key.get());
+      for (int i = 0; i < matrix.getRows(); i++) {
+        double dotProduct = matrix.getRow(i).dot(v);
+        if (BytesUtil.getRowIndex(key.get()) == i) {
+          dotProduct = 0;
+        }
+        put.add(Constants.COLUMNFAMILY, Bytes.toBytes(String
+            .valueOf(i)), Bytes.toBytes(dotProduct));
+      }
+
+      context.write(key, put);
+    }
+
+    @Override
+    public Configuration getConf() {
+      return conf;
+    }
+
+    @Override
+    public void setConf(Configuration conf) {
+      this.conf = conf;
+      try {
+        matrix = new DenseMatrix(new HamaConfiguration(conf), conf
+            .get("input.matrix"));
+      } catch (IOException e) {
+        e.printStackTrace();
+      }
+
+    }
+  }
+}
+}}}
+