eclipse写MAPREDUCE程序对HBase表进行操作之 IndexBuilder(对已有表建索引)

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eclipse写MAPREDUCE程序对HBase表进行操作之 IndexBuilder(对已有表建索引)

开源 hbase的example/mapreduce里有个类IndexBuilder是用来对已有表建索引的。其代码有一点点需要修改

[java] view plaincopy
conf.set(TableInputFormat.SCAN, TableMapReduceUtil.convertScanToString(new Scan()));  
conf.set(TableInputFormat.SCAN, convertScanToString(new Scan()));  

上面的改为下面的，为什么呢，因为TableMapReduceUtil类的那个函数是private的（也许以前是public吧，我用的是hbase-0.90.3），所以需要将那个函数的代码复制到当前任务类里

好了，上代码吧：

[java] view plaincopy
/** 
 * 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 hbase.test;  
  
import java.io.ByteArrayOutputStream;  
import java.io.DataOutputStream;  
import java.io.IOException;  
import java.util.HashMap;  
  
import org.apache.hadoop.conf.Configuration;  
import org.apache.hadoop.hbase.HBaseConfiguration;  
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.MultiTableOutputFormat;  
import org.apache.hadoop.hbase.mapreduce.TableInputFormat;  
import org.apache.hadoop.hbase.util.Base64;  
import org.apache.hadoop.hbase.util.Bytes;  
import org.apache.hadoop.io.Writable;  
import org.apache.hadoop.mapreduce.Job;  
import org.apache.hadoop.mapreduce.Mapper;  
import org.apache.hadoop.util.GenericOptionsParser;  
  
/** 
 * Example map/reduce job to construct index tables that can be used to quickly 
 * find a row based on the value of a column. It demonstrates: 
 * <ul> 
 * <li>Using TableInputFormat and TableMapReduceUtil to use an HTable as input 
 * to a map/reduce job.</li> 
 * <li>Passing values from main method to children via the configuration.</li> 
 * <li>Using MultiTableOutputFormat to output to multiple tables from a 
 * map/reduce job.</li> 
 * <li>A real use case of building a secondary index over a table.</li> 
 * </ul> 
 *  
 * <h3>Usage</h3> 
 *  
 * <p> 
 * Modify ${HADOOP_HOME}/conf/hadoop-env.sh to include the hbase jar, the 
 * zookeeper jar, the examples output directory, and the hbase conf directory in 
 * HADOOP_CLASSPATH, and then run 
 * <tt><strong>bin/hadoop org.apache.hadoop.hbase.mapreduce.IndexBuilder TABLE_NAME COLUMN_FAMILY ATTR [ATTR ...]</strong></tt> 
 * </p> 
 *  
 * <p> 
 * To run with the sample data provided in index-builder-setup.rb, use the 
 * arguments <strong><tt>people attributes name email phone</tt></strong>. 
 * </p> 
 *  
 * <p> 
 * This code was written against HBase 0.21 trunk. 
 * </p> 
 */  
public class IndexBuilder {  
  /** the column family containing the indexed row key */  
  public static final byte[] INDEX_COLUMN = Bytes.toBytes("INDEX");  
  /** the qualifier containing the indexed row key */  
  public static final byte[] INDEX_QUALIFIER = Bytes.toBytes("ROW");  
  
  /** 
   * Internal Mapper to be run by Hadoop. 
   */  
  public static class Map extends  
      Mapper<ImmutableBytesWritable, Result, ImmutableBytesWritable, Writable> {  
    private byte[] family;  
    private HashMap<byte[], ImmutableBytesWritable> indexes;  
  
    @Override  
    protected void map(ImmutableBytesWritable rowKey, Result result, Context context)  
        throws IOException, InterruptedException {  
      for(java.util.Map.Entry<byte[], ImmutableBytesWritable> index : indexes.entrySet()) {  
        byte[] qualifier = index.getKey();  
        ImmutableBytesWritable tableName = index.getValue();  
        byte[] value = result.getValue(family, qualifier);  
        if (value != null) {  
          // original: row 123 attribute:phone 555-1212  
          // index: row 555-1212 INDEX:ROW 123  
          Put put = new Put(value);  
          put.add(INDEX_COLUMN, INDEX_QUALIFIER, rowKey.get());  
          context.write(tableName, put);  
        }  
      }  
    }  
  
    @Override  
    protected void setup(Context context) throws IOException,  
        InterruptedException {  
      Configuration configuration = context.getConfiguration();  
      String tableName = configuration.get("index.tablename");  
      String[] fields = configuration.getStrings("index.fields");  
      String familyName = configuration.get("index.familyname");  
      family = Bytes.toBytes(familyName);  
      indexes = new HashMap<byte[], ImmutableBytesWritable>();  
      for(String field : fields) {  
        // if the table is "people" and the field to index is "email", then the  
        // index table will be called "people-email"  
        indexes.put(Bytes.toBytes(field),  
            new ImmutableBytesWritable(Bytes.toBytes(tableName + "-" + field)));  
      }  
    }  
  }  
  
  /** 
   * Job configuration. 
   */  
  public static Job configureJob(Configuration conf, String [] args)  
  throws IOException {  
    String tableName = args[0];  
    String columnFamily = args[1];  
    System.out.println("****" + tableName);  
    conf.set(TableInputFormat.SCAN, convertScanToString(new Scan()));  
    conf.set(TableInputFormat.INPUT_TABLE, tableName);  
    conf.set("index.tablename", tableName);  
    conf.set("index.familyname", columnFamily);  
    String[] fields = new String[args.length - 2];  
    for(int i = 0; i < fields.length; i++) {  
      fields[i] = args[i + 2];  
    }  
    conf.setStrings("index.fields", fields);  
    //conf.set("index.familyname", "attributes");  
    Job job = new Job(conf, tableName);  
    job.setJarByClass(IndexBuilder.class);  
    job.setMapperClass(Map.class);  
    job.setNumReduceTasks(0);  
    job.setInputFormatClass(TableInputFormat.class);  
    job.setOutputFormatClass(MultiTableOutputFormat.class);  
    return job;  
  }  
  
  public static void main(String[] args) throws Exception {  
    Configuration conf = HBaseConfiguration.create();  
    conf.set("hbase.zookeeper.quorum", "node2,node4,node3");  
    //conf.set("fs.default.name","hdfs://node1");     
    //conf.set("mapred.job.tracker","node1:54311");  
    String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();  
    if(otherArgs.length < 3) {  
      System.err.println("Only " + otherArgs.length + " arguments supplied, required: 3");  
      System.err.println("Usage: IndexBuilder <TABLE_NAME> <COLUMN_FAMILY> <ATTR> [<ATTR> ...]");  
      System.exit(-1);  
    }  
    Job job = configureJob(conf, otherArgs);  
    System.exit(job.waitForCompletion(true) ? 0 : 1);  
  }   
  private static String convertScanToString(Scan scan) throws IOException {  
        ByteArrayOutputStream out = new ByteArrayOutputStream();  
        DataOutputStream dos = new DataOutputStream(out);  
        scan.write(dos);  
        return Base64.encodeBytes(out.toByteArray());  
    }  
}  

大家看到了，我是放在hbase.test包里的，于是我将这个包打成jar包，然后放到hadoop集群里，执行hadoop jar mapreduceindexbuilder.jar 'it', 'f1', 'q1'

之所以这样写，因为我export的时候已经选了类了，所以不用再输类名，接下来的三个参数分别是表名，列族名，修饰符名

只是简单的测试而已。

一直报错。

出现下面的异常，主要就是CLASSNOTFOUNDEXCEPTION
大部分此类问题都是因为HADOOP_CLASSPATH没有设置好，只要将hbase的jar包hbase-0.90.3.jar及zookeeper的jar包(这个大家都知道自己用的是哪个哈)的路径添加进去便可以了。
但是今天仔细检查了好几遍HADOOP_CLASSPATH 发现hbase和zookeeper的jar包都在啊。

还需要注意的两点是：

job.setJarByClass(IndexBuilder.class); 这句一定要有，没有肯定找不到的！

map类放在执行main函数的类里，必须将map类设置成static才行
最后灵光一闪，会不会是自己打的jar包没有全啊，于是将整个项目export成一个jar包，然后便可以了。
唉！！！！！！！！！！
一定要将整个项目打成jar包啊！！！否则不行，切记！！！
12/01/09 16:06:23 INFO mapred.JobClient: Task Id : attempt_201201091352_0009_m_000000_1, Status : FAILED
java.lang.RuntimeException: java.lang.ClassNotFoundException: org.apache.hadoop.hbase.mapreduce.MultiTableOutputFormat
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:996)
at org.apache.hadoop.mapreduce.JobContext.getOutputFormatClass(JobContext.java:248)
at org.apache.hadoop.mapred.Task.initialize(Task.java:501)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:308)
at org.apache.hadoop.mapred.Child$4.run(Child.java:270)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1127)
at org.apache.hadoop.mapred.Child.main(Child.java:264)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.hbase.mapreduce.MultiTableOutputFormat
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:247)
at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:943)
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:994)
... 8 more

12/01/09 16:06:25 INFO mapred.JobClient: Task Id : attempt_201201091352_0009_m_000000_2, Status : FAILED
Error: java.lang.ClassNotFoundException: org.apache.zookeeper.KeeperException
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
at org.apache.hadoop.hbase.mapreduce.TableInputFormat.setConf(TableInputFormat.java:91)
at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:62)
at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:117)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:615)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:325)
at org.apache.hadoop.mapred.Child$4.run(Child.java:270)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1127)
at org.apache.hadoop.mapred.Child.main(Child.java:264)

我的表是两个，原表 it ,列族 f1,f2;修饰符f1:q1

索引表 it-q1:列族INDEX,修饰符INDEX:ROW

执行前it-q1为空，it为

hbase(main):031:0> scan 'it'
ROW                           COLUMN+CELL
001                          column=f1:q1, timestamp=1326076812129, value=009
001                          column=f1:q2, timestamp=1326076847867, value=123
002                          column=f1:q1, timestamp=1326076862300, value=008
003                          column=f1:q1, timestamp=1326076870450, value=007
004                          column=f1:q1, timestamp=1326076884825, value=006
005                          column=f1:q1, timestamp=1326076890460, value=005
006                          column=f1:q1, timestamp=1326076895971, value=004
007                          column=f1:q1, timestamp=1326076901697, value=003
008                          column=f1:q1, timestamp=1326076906960, value=002
009                          column=f1:q1, timestamp=1326076913531, value=001
010                          column=f1:q1, timestamp=1326076921461, value=000
020                          column=f1:q1, timestamp=1326109481769, value=20
030                          column=f1:q1, timestamp=1326109530945, value=10
12 row(s) in 0.0590 seconds

执行之后 it-f1表为：

hbase(main):032:0> scan 'it-q1'
ROW                           COLUMN+CELL
000                          column=INDEX:ROW, timestamp=1326109548266, value=010
001                          column=INDEX:ROW, timestamp=1326109548266, value=009
002                          column=INDEX:ROW, timestamp=1326109548266, value=008
003                          column=INDEX:ROW, timestamp=1326109548266, value=007
004                          column=INDEX:ROW, timestamp=1326109548266, value=006
005                          column=INDEX:ROW, timestamp=1326109548266, value=005
006                          column=INDEX:ROW, timestamp=1326109548266, value=004
007                          column=INDEX:ROW, timestamp=1326109548266, value=003
008                          column=INDEX:ROW, timestamp=1326109548266, value=002
009                          column=INDEX:ROW, timestamp=1326109548266, value=001
10                           column=INDEX:ROW, timestamp=1326109548266, value=030
20                           column=INDEX:ROW, timestamp=1326109548266, value=020
12 row(s) in 0.0600 seconds

执行的状态显示：

hadoop jar mapindexbuilder.jar it f1 q1

****it
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:host.name=node1
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:java.version=1.6.0_16
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:java.vendor=Sun Microsystems Inc.
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:java.home=/usr/java/jdk1.6.0_16/jre
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:java.class.path=这个太长了，删去了，下面带ip的信息也删了，呵呵

12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:java.library.path=/usr/lib/hadoop-0.20/lib/native/Linux-amd64-64
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:java.io.tmpdir=/tmp
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:java.compiler=<NA>
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:os.name=Linux
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:os.arch=amd64
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:os.version=2.6.18-194.el5
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:user.name=root
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:user.home=/root
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Client environment:user.dir=/root/workspace/wang
12/01/09 19:45:44 INFO zookeeper.ZooKeeper: Initiating client connection, connectString=node3:2181,node4:2181,node2:2181 sessionTimeout=180000 watcher=hconnection
12/01/09 19:45:44 INFO zookeeper.ClientCnxn: Opening socket connection to server node4/

12/01/09 19:45:44 INFO zookeeper.ClientCnxn: Socket connection established to node4/, initiating session
12/01/09 19:45:44 INFO zookeeper.ClientCnxn: Session establishment complete on server node4/, sessionid = 0x334c10a876b00b6, negotiated timeout = 180000
12/01/09 19:45:44 INFO mapreduce.TableInputFormatBase: running server=6, map range low=0, map range high=-6
12/01/09 19:45:45 INFO mapred.JobClient: Running job: job_201201091352_0019
12/01/09 19:45:46 INFO mapred.JobClient: map 0% reduce 0%
12/01/09 19:45:50 INFO mapred.JobClient: map 100% reduce 0%
12/01/09 19:45:50 INFO mapred.JobClient: Job complete: job_201201091352_0019
12/01/09 19:45:50 INFO mapred.JobClient: Counters: 12
12/01/09 19:45:50 INFO mapred.JobClient:   Job Counters
12/01/09 19:45:50 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=3061
12/01/09 19:45:50 INFO mapred.JobClient:     Total time spent by all reduces waiting after reserving slots (ms)=0
12/01/09 19:45:50 INFO mapred.JobClient:     Total time spent by all maps waiting after reserving slots (ms)=0
12/01/09 19:45:50 INFO mapred.JobClient:     Rack-local map tasks=1
12/01/09 19:45:50 INFO mapred.JobClient:     Launched map tasks=1
12/01/09 19:45:50 INFO mapred.JobClient:     SLOTS_MILLIS_REDUCES=0
12/01/09 19:45:50 INFO mapred.JobClient:   FileSystemCounters
12/01/09 19:45:50 INFO mapred.JobClient:     HDFS_BYTES_READ=56
12/01/09 19:45:50 INFO mapred.JobClient:     FILE_BYTES_WRITTEN=56750
12/01/09 19:45:50 INFO mapred.JobClient:   Map-Reduce Framework
12/01/09 19:45:50 INFO mapred.JobClient:     Map input records=12
12/01/09 19:45:50 INFO mapred.JobClient:     Spilled Records=0
12/01/09 19:45:50 INFO mapred.JobClient:     Map output records=12
12/01/09 19:45:50 INFO mapred.JobClient:     SPLIT_RAW_BYTES=56