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

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：

/**
* 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 = 0x334c10a876b00b5, negotiated timeout = 180000

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