JDK,Eclipse的安装请参考：Ubuntu 安装 搭建 J2EE 开发环境
Ant安装：
下载ant:
解压Ant:
tar -xvzf apache-ant-1.9.2-bin.tar.gz
移动重命名：
mv apache-ant-1.9.2/ ~/opt/
mv apache-ant-1.9.2/ ant
配置环境变量，添加ANT_HOME，和$ANT_HOME/bin：
sudo vim /etc/profile
.......................
export ANT_HOME=/opt/ant
export PATH=$PATH:$ANT_HOME/bin
.......................
source /etc/profile
测试是否生效：
ant -version
Apache Ant(TM) version 1.9.2 compiled on July 8 2013
Hadoop Eclipse 插件安装：
Hadoop的eclipse插件需要自行安装编译，也很简单，用ant进行编译打包
cd /opt/hadoop-1.2.1/src/contrib/eclipse-plugin
此处贴出build.xml全部和META-INFO改动的：
build.xml
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!--
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<!-- build.xml -->
<project default="jar">
<import file="../build-contrib.xml"/>
<property location="/opt/eclipse"/>
<property value="1.2.1"/>
<path>
<fileset dir="${eclipse.home}/plugins/">
<include/>
<include/>
<include/>
<include/>
<include/>
<include/>
<include/>
<include/>
<include/>
<include/>
</fileset>
</path>
<!-- Override classpath to include Eclipse SDK jars -->
<path>
<pathelement location="${build.classes}"/>
<pathelement location="${hadoop.root}/build/classes"/>
<fileset dir="${hadoop.root}">
<include />
</fileset>
<path refid="eclipse-sdk-jars"/>
</path>
<!-- Skip building if eclipse.home is unset. -->
<target unless="eclipse.home">
<property value="yes"/>
<echo message="eclipse.home unset: skipping eclipse plugin"/>
</target>
<target depends="init, ivy-retrieve-common" unless="skip.contrib">
<echo message="contrib: ${name}"/>
<javac
encoding="${build.encoding}"
srcdir="${src.dir}"
includes="**/*.java"
destdir="${build.classes}"
debug="${javac.debug}"
deprecation="${javac.deprecation}"
includeantruntime="on">
<classpath refid="classpath"/>
</javac>
</target>
<!-- Override jar target to specify manifest -->
<target depends="compile" unless="skip.contrib">
<mkdir dir="${build.dir}/lib"/>
<!-- <copy file="${hadoop.root}/build/hadoop-core-${version}.jar" tofile="${build.dir}/lib/hadoop-core.jar" verbose="true"/> -->
<!-- <copy file="${hadoop.root}/build/ivy/lib/Hadoop/common/commons-cli-${commons-cli.version}.jar" todir="${build.dir}/lib" verbose="true"/>-->
<copy file="${hadoop.root}/hadoop-core-${version}.jar" tofile="${build.dir}/lib/hadoop-core.jar" verbose="true"/>
<copy file="${hadoop.root}/lib/commons-cli-${commons-cli.version}.jar" tofile="${build.dir}/lib/commons-cli.jar" verbose="true"/>
<copy file="${hadoop.root}/lib/commons-configuration-1.6.jar" tofile="${build.dir}/lib/commons-configuration.jar" verbose="true"/>
<copy file="${hadoop.root}/lib/commons-httpclient-3.0.1.jar" tofile="${build.dir}/lib/commons-httpclient.jar" verbose="true"/>
<copy file="${hadoop.root}/lib/commons-lang-2.4.jar" tofile="${build.dir}/lib/commons-lang.jar" verbose="true"/>
<copy file="${hadoop.root}/lib/jackson-core-asl-1.8.8.jar" tofile="${build.dir}/lib/jackson-core-asl.jar" verbose="true"/>
<copy file="${hadoop.root}/lib/jackson-mapper-asl-1.8.8.jar" tofile="${build.dir}/lib/jackson-mapper-asl.jar" verbose="true"/>
<jar
jarfile="${build.dir}/hadoop-${name}-${version}.jar"
manifest="${root}/META-INF/MANIFEST.MF">
<fileset dir="${build.dir}" includes="classes/ lib/"/>
<fileset dir="${root}" includes="resources/ plugin.xml"/>
</jar>
</target>
</project>
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搭建Hadoop环境（在Winodws环境下用虚拟机虚拟两个Ubuntu系统进行搭建）