使用Hadoop已经有一段时间了,从开始的迷茫,到各种的尝试,到现在组合应用….慢慢地涉及到数据处理的事情,已经离不开hadoop了。Hadoop在大数据领域的成功,更引发了它本身的加速发展。现在Hadoop家族产品,已经达到20个了之多。
有必要对自己的知识做一个整理了,把产品和技术都串起来。不仅能加深印象,更可以对以后的技术方向,技术选型做好基础准备。
一句话产品介绍:
Hadoop的MapReduce环境是一个复杂的编程环境,所以我们要尽可能地简化构建MapReduce项目的过程。Maven是一个很不错的自动化项目构建工具,通过Maven来帮助我们从复杂的环境配置中解脱出来,从而标准化开发过程。所以,写MapReduce之前,让我们先花点时间把刀磨快!!当然,除了Maven还有其他的选择Gradle(推荐), Ivy….
目录
Apache Maven,是一个Java的项目管理及自动构建工具,由Apache软件基金会所提供。基于项目对象模型(缩写:POM)概念,Maven利用一个中央信息片断能管理一个项目的构建、报告和文档等步骤。曾是Jakarta项目的子项目,现为独立Apache项目。
maven的开发者在他们开发网站上指出,maven的目标是要使得项目的构建更加容易,它把编译、打包、测试、发布等开发过程中的不同环节有机的串联了起来,并产生一致的、高质量的项目信息,使得项目成员能够及时地得到反馈。maven有效地支持了测试优先、持续集成,体现了鼓励沟通,及时反馈的软件开发理念。如果说Ant的复用是建立在”拷贝–粘贴”的基础上的,那么Maven通过插件的机制实现了项目构建逻辑的真正复用。
sudo add-apt-repository ppa:natecarlson/maven3
sudo apt-get update && sudo apt-get install maven3
mvn3 -version
如上图所示,我们可以选择在win中开发,也可以在linux中开发,本地启动Hadoop或者远程调用Hadoop,标配的工具都是Maven和Eclipse。
Hadoop集群系统环境:
mvn3 archetype:generate -DarchetypeGroupId=org.apache.maven.archetypes -DgroupId=org.conan.myhadoop.mr
-DartifactId=myHadoop -DpackageName=org.conan.myhadoop.mr -Dversion=1.0-SNAPSHOT -DinteractiveMode=false
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Stub Project (No POM) 1
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] >>> maven-archetype-plugin:2.2:generate (default-cli) @ standalone-pom >>>
[INFO]
[INFO] <<< maven-archetype-plugin:2.2:generate (default-cli) @ standalone-pom <<<
[INFO]
[INFO] --- maven-archetype-plugin:2.2:generate (default-cli) @ standalone-pom ---
[INFO] Generating project in Batch mode
[INFO] No archetype defined. Using maven-archetype-quickstart (org.apache.maven.archetypes:maven-archetype-quickstart:1.
0)
Downloading: http://repo.maven.apache.org/maven2/org/apache/maven/archetypes/maven-archetype-quickstart/1.0/maven-archet
ype-quickstart-1.0.jar
Downloaded: http://repo.maven.apache.org/maven2/org/apache/maven/archetypes/maven-archetype-quickstart/1.0/maven-archety
pe-quickstart-1.0.jar (5 KB at 4.3 KB/sec)
Downloading: http://repo.maven.apache.org/maven2/org/apache/maven/archetypes/maven-archetype-quickstart/1.0/maven-archet
ype-quickstart-1.0.pom
Downloaded: http://repo.maven.apache.org/maven2/org/apache/maven/archetypes/maven-archetype-quickstart/1.0/maven-archety
pe-quickstart-1.0.pom (703 B at 1.6 KB/sec)
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating project from Old (1.x) Archetype: maven-archetype-quickstart:1.0
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: org.conan.myhadoop.mr
[INFO] Parameter: packageName, Value: org.conan.myhadoop.mr
[INFO] Parameter: package, Value: org.conan.myhadoop.mr
[INFO] Parameter: artifactId, Value: myHadoop
[INFO] Parameter: basedir, Value: D:\workspace\java
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] project created from Old (1.x) Archetype in dir: D:\workspace\java\myHadoop
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 8.896s
[INFO] Finished at: Sun Sep 29 20:57:07 CST 2013
[INFO] Final Memory: 9M/179M
[INFO] ------------------------------------------------------------------------
进入项目
cd myHadoop
执行mvn命令
mvn3 clean install
Downloaded: http://repo.maven.apache.org/maven2/org/codehaus/plexus/plexus-digest/1.0/plexus-digest-1.0.jar (12 KB at 28.9 KB/sec)
Downloaded: http://repo.maven.apache.org/maven2/org/codehaus/plexus/plexus-utils/3.0.5/plexus-utils-3.0.5.jar (226 KB at 145.0 KB/sec)
[INFO] Installing /home/justhacker/projects/codes/myHadoop/target/myHadoop-1.0-SNAPSHOT.jar to /home/justhacker/.m2/repository/org/conan/myhadoop/mr/myHadoop/1.0-SNAPSHOT/myHadoop-1.0-SNAPSHOT.jar
[INFO] Installing /home/justhacker/projects/codes/myHadoop/pom.xml to /home/justhacker/.m2/repository/org/conan/myhadoop/mr/myHadoop/1.0-SNAPSHOT/myHadoop-1.0-SNAPSHOT.pom
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 58.154 s
[INFO] Finished at: 2014-05-21T00:41:30+08:00
[INFO] Final Memory: 13M/150M
[INFO] -----------------------------------------
2). 导入项目到eclipse
我们创建好了一个基本的maven项目,然后导入到eclipse中。 这里我们最好已安装好了Maven的插件。
3). 增加hadoop依赖
这里我使用hadoop-1.0.3版本,修改文件:pom.xml
~ vi pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.conan.myhadoop.mr</groupId>
<artifactId>myHadoop</artifactId>
<packaging>jar</packaging>
<version>1.0-SNAPSHOT</version>
<name>myHadoop</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-core</artifactId>
<version>1.0.3</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.4</version>
<scope>test</scope>
</dependency>
</dependencies>
</project>
4). 下载依赖
下载依赖:
~ mvn3 clean install
在eclipse中刷新项目:
项目的依赖程序,被自动加载的库路径下面。
5). 从Hadoop集群环境下载hadoop配置文件
查看core-site.xml
<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
<property>
<name>fs.default.name</name>
<value>hdfs://master:9000</value>
</property>
<property>
<name>hadoop.tmp.dir</name>
<value>/home/conan/hadoop/tmp</value>
</property>
<property>
<name>io.sort.mb</name>
<value>256</value>
</property>
</configuration>
查看hdfs-site.xml
<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
<property>
<name>dfs.data.dir</name>
<value>/home/conan/hadoop/data</value>
</property>
<property>
<name>dfs.replication</name>
<value>1</value>
</property>
<property>
<name>dfs.permissions</name>
<value>false</value>
</property>
</configuration>
查看mapred-site.xml
<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
<property>
<name>mapred.job.tracker</name>
<value>hdfs://master:9001</value>
</property>
</configuration>
保存在src/main/resources/hadoop目录下面
删除原自动生成的文件:App.java和AppTest.java
6).配置本地host,增加master的域名指向
vi /etc/hosts
111.0.216.178 master
编写一个简单的MapReduce程序,实现wordcount功能。
新一个Java文件:WordCount.java
package org.conan.myhadoop.mr;
import java.io.IOException;
import java.util.Iterator;
import java.util.StringTokenizer;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.TextInputFormat;
import org.apache.hadoop.mapred.TextOutputFormat;
public class WordCount {
public static class WordCountMapper extends MapReduceBase implements Mapper<Object, Text, Text, IntWritable> {
private final static IntWritable one = new IntWritable(1);
private Text word = new Text();
@Override
public void map(Object key, Text value, OutputCollector<Text, IntWritable> output, Reporter reporter) throws IOException {
StringTokenizer itr = new StringTokenizer(value.toString());
while (itr.hasMoreTokens()) {
word.set(itr.nextToken());
output.collect(word, one);
}
}
}
public static class WordCountReducer extends MapReduceBase implements Reducer<Text, IntWritable, Text, IntWritable> {
private IntWritable result = new IntWritable();
@Override
public void reduce(Text key, Iterator values, OutputCollector<Text, IntWritable> output, Reporter reporter) throws IOException {
int sum = 0;
while (values.hasNext()) {
sum += values.next().get();
}
result.set(sum);
output.collect(key, result);
}
}
public static void main(String[] args) throws Exception {
String input = "hdfs://192.168.1.210:9000/user/hdfs/o_t_account";
String output = "hdfs://192.168.1.210:9000/user/hdfs/o_t_account/result";
JobConf conf = new JobConf(WordCount.class);
conf.setJobName("WordCount");
conf.addResource("classpath:/hadoop/core-site.xml");
conf.addResource("classpath:/hadoop/hdfs-site.xml");
conf.addResource("classpath:/hadoop/mapred-site.xml");
conf.setOutputKeyClass(Text.class);
conf.setOutputValueClass(IntWritable.class);
conf.setMapperClass(WordCountMapper.class);
conf.setCombinerClass(WordCountReducer.class);
conf.setReducerClass(WordCountReducer.class);
conf.setInputFormat(TextInputFormat.class);
conf.setOutputFormat(TextOutputFormat.class);
FileInputFormat.setInputPaths(conf, new Path(input));
FileOutputFormat.setOutputPath(conf, new Path(output));
JobClient.runJob(conf);
System.exit(0);
}
}
启动Java APP.
2013-9-30 19:50:49 org.apache.hadoop.util.NativeCodeLoader
警告: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
2013-9-30 19:50:49 org.apache.hadoop.mapred.JobClient copyAndConfigureFiles
警告: Use GenericOptionsParser for parsing the arguments. Applications should implement Tool for the same.
2013-9-30 19:50:49 org.apache.hadoop.mapred.JobClient copyAndConfigureFiles
警告: No job jar file set. User classes may not be found. See JobConf(Class) or JobConf#setJar(String).
2013-9-30 19:50:49 org.apache.hadoop.io.compress.snappy.LoadSnappy
警告: Snappy native library not loaded
2013-9-30 19:50:49 org.apache.hadoop.mapred.FileInputFormat listStatus
信息: Total input paths to process : 4
2013-9-30 19:50:50 org.apache.hadoop.mapred.JobClient monitorAndPrintJob
信息: Running job: job_local_0001
2013-9-30 19:50:50 org.apache.hadoop.mapred.Task initialize
信息: Using ResourceCalculatorPlugin : null
2013-9-30 19:50:50 org.apache.hadoop.mapred.MapTask runOldMapper
信息: numReduceTasks: 1
2013-9-30 19:50:50 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: io.sort.mb = 100
2013-9-30 19:50:50 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: data buffer = 79691776/99614720
2013-9-30 19:50:50 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: record buffer = 262144/327680
2013-9-30 19:50:50 org.apache.hadoop.mapred.MapTask$MapOutputBuffer flush
信息: Starting flush of map output
2013-9-30 19:50:50 org.apache.hadoop.mapred.MapTask$MapOutputBuffer sortAndSpill
信息: Finished spill 0
2013-9-30 19:50:50 org.apache.hadoop.mapred.Task done
信息: Task:attempt_local_0001_m_000000_0 is done. And is in the process of commiting
2013-9-30 19:50:51 org.apache.hadoop.mapred.JobClient monitorAndPrintJob
信息: map 0% reduce 0%
2013-9-30 19:50:53 org.apache.hadoop.mapred.LocalJobRunner$Job statusUpdate
信息: hdfs://192.168.1.210:9000/user/hdfs/o_t_account/part-m-00003:0+119
2013-9-30 19:50:53 org.apache.hadoop.mapred.Task sendDone
信息: Task ‘attempt_local_0001_m_000000_0‘ done.
2013-9-30 19:50:53 org.apache.hadoop.mapred.Task initialize
信息: Using ResourceCalculatorPlugin : null
2013-9-30 19:50:53 org.apache.hadoop.mapred.MapTask runOldMapper
信息: numReduceTasks: 1
2013-9-30 19:50:53 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: io.sort.mb = 100
2013-9-30 19:50:53 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: data buffer = 79691776/99614720
2013-9-30 19:50:53 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: record buffer = 262144/327680
2013-9-30 19:50:53 org.apache.hadoop.mapred.MapTask$MapOutputBuffer flush
信息: Starting flush of map output
2013-9-30 19:50:53 org.apache.hadoop.mapred.MapTask$MapOutputBuffer sortAndSpill
信息: Finished spill 0
2013-9-30 19:50:53 org.apache.hadoop.mapred.Task done
信息: Task:attempt_local_0001_m_000001_0 is done. And is in the process of commiting
2013-9-30 19:50:54 org.apache.hadoop.mapred.JobClient monitorAndPrintJob
信息: map 100% reduce 0%
2013-9-30 19:50:56 org.apache.hadoop.mapred.LocalJobRunner$Job statusUpdate
信息: hdfs://192.168.1.210:9000/user/hdfs/o_t_account/part-m-00000:0+113
2013-9-30 19:50:56 org.apache.hadoop.mapred.Task sendDone
信息: Task ‘attempt_local_0001_m_000001_0‘ done.
2013-9-30 19:50:56 org.apache.hadoop.mapred.Task initialize
信息: Using ResourceCalculatorPlugin : null
2013-9-30 19:50:56 org.apache.hadoop.mapred.MapTask runOldMapper
信息: numReduceTasks: 1
2013-9-30 19:50:56 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: io.sort.mb = 100
2013-9-30 19:50:56 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: data buffer = 79691776/99614720
2013-9-30 19:50:56 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: record buffer = 262144/327680
2013-9-30 19:50:56 org.apache.hadoop.mapred.MapTask$MapOutputBuffer flush
信息: Starting flush of map output
2013-9-30 19:50:56 org.apache.hadoop.mapred.MapTask$MapOutputBuffer sortAndSpill
信息: Finished spill 0
2013-9-30 19:50:56 org.apache.hadoop.mapred.Task done
信息: Task:attempt_local_0001_m_000002_0 is done. And is in the process of commiting
2013-9-30 19:50:59 org.apache.hadoop.mapred.LocalJobRunner$Job statusUpdate
信息: hdfs://192.168.1.210:9000/user/hdfs/o_t_account/part-m-00001:0+110
2013-9-30 19:50:59 org.apache.hadoop.mapred.LocalJobRunner$Job statusUpdate
信息: hdfs://192.168.1.210:9000/user/hdfs/o_t_account/part-m-00001:0+110
2013-9-30 19:50:59 org.apache.hadoop.mapred.Task sendDone
信息: Task ‘attempt_local_0001_m_000002_0‘ done.
2013-9-30 19:50:59 org.apache.hadoop.mapred.Task initialize
信息: Using ResourceCalculatorPlugin : null
2013-9-30 19:50:59 org.apache.hadoop.mapred.MapTask runOldMapper
信息: numReduceTasks: 1
2013-9-30 19:50:59 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: io.sort.mb = 100
2013-9-30 19:50:59 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: data buffer = 79691776/99614720
2013-9-30 19:50:59 org.apache.hadoop.mapred.MapTask$MapOutputBuffer
信息: record buffer = 262144/327680
2013-9-30 19:50:59 org.apache.hadoop.mapred.MapTask$MapOutputBuffer flush
信息: Starting flush of map output
2013-9-30 19:50:59 org.apache.hadoop.mapred.MapTask$MapOutputBuffer sortAndSpill
信息: Finished spill 0
2013-9-30 19:50:59 org.apache.hadoop.mapred.Task done
信息: Task:attempt_local_0001_m_000003_0 is done. And is in the process of commiting
2013-9-30 19:51:02 org.apache.hadoop.mapred.LocalJobRunner$Job statusUpdate
信息: hdfs://192.168.1.210:9000/user/hdfs/o_t_account/part-m-00002:0+79
2013-9-30 19:51:02 org.apache.hadoop.mapred.Task sendDone
信息: Task ‘attempt_local_0001_m_000003_0‘ done.
2013-9-30 19:51:02 org.apache.hadoop.mapred.Task initialize
信息: Using ResourceCalculatorPlugin : null
2013-9-30 19:51:02 org.apache.hadoop.mapred.LocalJobRunner$Job statusUpdate
信息:
2013-9-30 19:51:02 org.apache.hadoop.mapred.Merger$MergeQueue merge
信息: Merging 4 sorted segments
2013-9-30 19:51:02 org.apache.hadoop.mapred.Merger$MergeQueue merge
信息: Down to the last merge-pass, with 4 segments left of total size: 442 bytes
2013-9-30 19:51:02 org.apache.hadoop.mapred.LocalJobRunner$Job statusUpdate
信息:
2013-9-30 19:51:02 org.apache.hadoop.mapred.Task done
信息: Task:attempt_local_0001_r_000000_0 is done. And is in the process of commiting
2013-9-30 19:51:02 org.apache.hadoop.mapred.LocalJobRunner$Job statusUpdate
信息:
2013-9-30 19:51:02 org.apache.hadoop.mapred.Task commit
信息: Task attempt_local_0001_r_000000_0 is allowed to commit now
2013-9-30 19:51:02 org.apache.hadoop.mapred.FileOutputCommitter commitTask
信息: Saved output of task ‘attempt_local_0001_r_000000_0‘ to hdfs://192.168.1.210:9000/user/hdfs/o_t_account/result
2013-9-30 19:51:05 org.apache.hadoop.mapred.LocalJobRunner$Job statusUpdate
信息: reduce > reduce
2013-9-30 19:51:05 org.apache.hadoop.mapred.Task sendDone
信息: Task ‘attempt_local_0001_r_000000_0‘ done.
2013-9-30 19:51:06 org.apache.hadoop.mapred.JobClient monitorAndPrintJob
信息: map 100% reduce 100%
2013-9-30 19:51:06 org.apache.hadoop.mapred.JobClient monitorAndPrintJob
信息: Job complete: job_local_0001
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Counters: 20
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: File Input Format Counters
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Bytes Read=421
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: File Output Format Counters
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Bytes Written=348
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: FileSystemCounters
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: FILE_BYTES_READ=7377
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: HDFS_BYTES_READ=1535
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: FILE_BYTES_WRITTEN=209510
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: HDFS_BYTES_WRITTEN=348
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Map-Reduce Framework
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Map output materialized bytes=458
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Map input records=11
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Reduce shuffle bytes=0
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Spilled Records=30
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Map output bytes=509
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Total committed heap usage (bytes)=1838546944
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Map input bytes=421
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: SPLIT_RAW_BYTES=452
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Combine input records=22
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Reduce input records=15
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Reduce input groups=13
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Combine output records=15
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Reduce output records=13
2013-9-30 19:51:06 org.apache.hadoop.mapred.Counters log
信息: Map output records=22
成功运行了wordcount程序,通过命令我们查看输出结果
~ hadoop fs -ls hdfs://111.0.216.178:9000/user/hdfs/o_t_account/result
Found 2 items
-rw-r--r-- 3 Administrator supergroup 0 2013-09-30 19:51 /user/hdfs/o_t_account/result/_SUCCESS
-rw-r--r-- 3 Administrator supergroup 348 2013-09-30 19:51 /user/hdfs/o_t_account/result/part-00000
~ hadoop fs -cat hdfs://111.0.216.178:9000/user/hdfs/o_t_account/result/part-00000
1,abc@163.com,2013-04-22 1
10,ade121@sohu.com,2013-04-23 1
11,addde@sohu.com,2013-04-23 1
17:21:24.0 5
2,dedac@163.com,2013-04-22 1
20:21:39.0 6
3,qq8fed@163.com,2013-04-22 1
4,qw1@163.com,2013-04-22 1
5,af3d@163.com,2013-04-22 1
6,ab34@163.com,2013-04-22 1
7,q8d1@gmail.com,2013-04-23 1
8,conan@gmail.com,2013-04-23 1
9,adeg@sohu.com,2013-04-23 1
这样,我们就实现了开发,通过Maven构建Hadoop依赖环境,在Eclipse中开发MapReduce的程序,然后运行JavaAPP。Hadoop应用会自动把我们的MR程序打成jar包,再上传的远程的hadoop环境中运行,返回日志在Eclipse控制台输出。
https://github.com/edagarli/maven_hadoop_template
大家可以下载这个项目,做为开发的起点。
~ git clone https://github.com/edagarli/maven_hadoop_template.git
同时这篇文章我收录到github优秀博客收集项目里https://github.com/edagarli/programming-articles-zh_CN
我们完成第一步,下面就将正式进入MapReduce开发实践。
转载请注明出处:http://blog.csdn.net/edagarli/article/details/26423041
原文地址:http://blog.csdn.net/edagarli/article/details/26423041