ubuntu12.04 安装JDK7

１、通过apt-get直接下载安装JDK

sudo apt-get install openjdk-7-jdk

执行之后会将ＪＤＫ安装到/usr/lib/jvm/java-7-openjdk-i386/

２、通过update-alternatives选择系统中使用的java

sudo update-alternatives --config java
有 3 个候选项可用于替换 java (提供 /usr/bin/java)。

  选择       路径                                         优先级  状态
------------------------------------------------------------
* 0            /usr/lib/jvm/java-6-openjdk-i386/jre/bin/java   1061      自动模式
            /usr/lib/jvm/java-6-openjdk-i386/jre/bin/java   1061      手动模式
            /usr/lib/jvm/java-6-sun/jre/bin/java            63        手动模式
            /usr/lib/jvm/java-7-openjdk-i386/jre/bin/java   1051      手动模式

要维持当前值[*]请按回车键，或者键入选择的编号：3       
update-alternatives: 使用 /usr/lib/jvm/java-7-openjdk-i386/jre/bin/java 来提供 /usr/bin/java (java)，于 手动模式 中。

实际是将/usr/bin/java链接到ＪＤＫ７上，保证执行java命令后，实际运行的是我们的目标版本

java -version
java version "1.7.0_09"
OpenJDK Runtime Environment (IcedTea7 2.3.3) (7u9-2.3.3-0ubuntu1~12.04.1)
OpenJDK Server VM (build 23.2-b09, mixed mode)

除了java外，还有javac、jar、javah、javap、jps、jconsole等

sudo update-alternatives --config javac
sudo update-alternatives --config jar 
sudo update-alternatives --config javah 
sudo update-alternatives --config javap 
sudo update-alternatives --config jps 
sudo update-alternatives --config jconsole

补充：jps -lv  用于查看java程序的启动参数，如java版本

二、全手动

１、访问http://www.oracle.com/technetwork/java/javase/downloads/index.html,下载jdk7

oracle没有提供deb的安装包，只能下载压缩包jdk-7u10-linux-i586.tar.gz

２、下载完成后，命令解压到/usr/lib/jvm

sudo tar zxvf ./jdk-7u10-linux-i586.tar.gz  -C /usr/lib/jvm  

3、为ＪＤＫ目录创建软连接到java-7-sun

sudo ln -s jdk1.7.0_10 java-7-sun 

4、将javac、jar、javah、javap等添加到候选列表

sudo update-alternatives --install /usr/bin/ControlPanel ControlPanel /usr/lib/jvm/java-7-sun/jre/bin/ControlPanel 300
sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/java-7-sun/jre/bin/java 300
sudo update-alternatives --install /usr/bin/java_vm java_vm /usr/lib/jvm/java-7-sun/jre/bin/java_vm 300
sudo update-alternatives --install /usr/bin/javaws javaws /usr/lib/jvm/java-7-sun/jre/bin/javaws 300
sudo update-alternatives --install /usr/bin/jcontrol jcontrol /usr/lib/jvm/java-7-sun/jre/bin/jcontrol 300
sudo update-alternatives --install /usr/bin/keytool keytool /usr/lib/jvm/java-7-sun/jre/bin/keytool 300
sudo update-alternatives --install /usr/bin/pack200 pack200 /usr/lib/jvm/java-7-sun/jre/bin/pack200 300
sudo update-alternatives --install /usr/bin/policytool policytool /usr/lib/jvm/java-7-sun/jre/bin/policytool 300
sudo update-alternatives --install /usr/bin/rmid rmid /usr/lib/jvm/java-7-sun/jre/bin/rmid 300
sudo update-alternatives --install /usr/bin/rmiregistry rmiregistry /usr/lib/jvm/java-7-sun/jre/bin/rmiregistry 300
sudo update-alternatives --install /usr/bin/unpack200 unpack200 /usr/lib/jvm/java-7-sun/jre/bin/unpack200 300
sudo update-alternatives --install /usr/bin/orbd orbd /usr/lib/jvm/java-7-sun/jre/bin/orbd 300
sudo update-alternatives --install /usr/bin/servertool servertool /usr/lib/jvm/java-7-sun/jre/bin/servertool 300
sudo update-alternatives --install /usr/bin/tnameserv tnameserv /usr/lib/jvm/java-7-sun/jre/bin/tnameserv 300
sudo update-alternatives --install /usr/bin/HtmlConverter HtmlConverter /usr/lib/jvm/java-7-sun/bin/HtmlConverter 300
sudo update-alternatives --install /usr/bin/appletviewer appletviewer /usr/lib/jvm/java-7-sun/bin/appletviewer 300
sudo update-alternatives --install /usr/bin/apt apt /usr/lib/jvm/java-7-sun/bin/apt 300
sudo update-alternatives --install /usr/bin/extcheck extcheck /usr/lib/jvm/java-7-sun/bin/extcheck 300
sudo update-alternatives --install /usr/bin/idlj idlj /usr/lib/jvm/java-7-sun/bin/idlj 300
sudo update-alternatives --install /usr/bin/jar jar /usr/lib/jvm/java-7-sun/bin/jar 300
sudo update-alternatives --install /usr/bin/jarsigner jarsigner /usr/lib/jvm/java-7-sun/bin/jarsigner 300
sudo update-alternatives --install /usr/bin/java-rmi.cgi java-rmi.cgi /usr/lib/jvm/java-7-sun/bin/java-rmi.cgi 300
sudo update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/java-7-sun/bin/javac 300
sudo update-alternatives --install /usr/bin/javadoc javadoc /usr/lib/jvm/java-7-sun/bin/javadoc 300
sudo update-alternatives --install /usr/bin/javah javah /usr/lib/jvm/java-7-sun/bin/javah 300
sudo update-alternatives --install /usr/bin/javap javap /usr/lib/jvm/java-7-sun/bin/javap 300
sudo update-alternatives --install /usr/bin/jconsole jconsole /usr/lib/jvm/java-7-sun/bin/jconsole 300
sudo update-alternatives --install /usr/bin/jdb jdb /usr/lib/jvm/java-7-sun/bin/jdb 300
sudo update-alternatives --install /usr/bin/jhat jhat /usr/lib/jvm/java-7-sun/bin/jhat 300
sudo update-alternatives --install /usr/bin/jinfo jinfo /usr/lib/jvm/java-7-sun/bin/jinfo 300
sudo update-alternatives --install /usr/bin/jmap jmap /usr/lib/jvm/java-7-sun/bin/jmap 300
sudo update-alternatives --install /usr/bin/jps jps /usr/lib/jvm/java-7-sun/bin/jps 300
sudo update-alternatives --install /usr/bin/jrunscript jrunscript /usr/lib/jvm/java-7-sun/bin/jrunscript 300
sudo update-alternatives --install /usr/bin/jsadebugd jsadebugd /usr/lib/jvm/java-7-sun/bin/jsadebugd 300
sudo update-alternatives --install /usr/bin/jstack jstack /usr/lib/jvm/java-7-sun/bin/jstack 300
sudo update-alternatives --install /usr/bin/jstat jstat /usr/lib/jvm/java-7-sun/bin/jstat 300
sudo update-alternatives --install /usr/bin/jstatd jstatd /usr/lib/jvm/java-7-sun/bin/jstatd 300
sudo update-alternatives --install /usr/bin/native2ascii native2ascii /usr/lib/jvm/java-7-sun/bin/native2ascii 300
sudo update-alternatives --install /usr/bin/rmic rmic /usr/lib/jvm/java-7-sun/bin/rmic 300
sudo update-alternatives --install /usr/bin/schemagen schemagen /usr/lib/jvm/java-7-sun/bin/schemagen 300
sudo update-alternatives --install /usr/bin/serialver serialver /usr/lib/jvm/java-7-sun/bin/serialver 300
sudo update-alternatives --install /usr/bin/wsgen wsgen /usr/lib/jvm/java-7-sun/bin/wsgen 300
sudo update-alternatives --install /usr/bin/wsimport wsimport /usr/lib/jvm/java-7-sun/bin/wsimport 300
sudo update-alternatives --install /usr/bin/xjc xjc /usr/lib/jvm/java-7-sun/bin/xjc 300

５、创建/usr/lib/jvm/.java-7-sun.jinfo ，输入以下的内容

name=java-7-sun-1.7.0_10
alias=java-7-sun
priority=63
section=non-free
jre ControlPanel /usr/lib/jvm/java-7-sun/jre/bin/ControlPanel
jre java /usr/lib/jvm/java-7-sun/jre/bin/java
jre java_vm /usr/lib/jvm/java-7-sun/jre/bin/java_vm
jre javaws /usr/lib/jvm/java-7-sun/jre/bin/javaws
jre jcontrol /usr/lib/jvm/java-7-sun/jre/bin/jcontrol
jre keytool /usr/lib/jvm/java-7-sun/jre/bin/keytool
jre pack200 /usr/lib/jvm/java-7-sun/jre/bin/pack200
jre policytool /usr/lib/jvm/java-7-sun/jre/bin/policytool
jre rmid /usr/lib/jvm/java-7-sun/jre/bin/rmid
jre rmiregistry /usr/lib/jvm/java-7-sun/jre/bin/rmiregistry
jre unpack200 /usr/lib/jvm/java-7-sun/jre/bin/unpack200
jre orbd /usr/lib/jvm/java-7-sun/jre/bin/orbd
jre servertool /usr/lib/jvm/java-7-sun/jre/bin/servertool
jre tnameserv /usr/lib/jvm/java-7-sun/jre/bin/tnameserv
jdk HtmlConverter /usr/lib/jvm/java-7-sun/bin/HtmlConverter
jdk appletviewer /usr/lib/jvm/java-7-sun/bin/appletviewer
jdk apt /usr/lib/jvm/java-7-sun/bin/apt
jdk extcheck /usr/lib/jvm/java-7-sun/bin/extcheck
jdk idlj /usr/lib/jvm/java-7-sun/bin/idlj
jdk jar /usr/lib/jvm/java-7-sun/bin/jar
jdk jarsigner /usr/lib/jvm/java-7-sun/bin/jarsigner
jdk java-rmi.cgi /usr/lib/jvm/java-7-sun/bin/java-rmi.cgi
jdk javac /usr/lib/jvm/java-7-sun/bin/javac
jdk javadoc /usr/lib/jvm/java-7-sun/bin/javadoc
jdk javah /usr/lib/jvm/java-7-sun/bin/javah
jdk javap /usr/lib/jvm/java-7-sun/bin/javap
jdk jconsole /usr/lib/jvm/java-7-sun/bin/jconsole
jdk jdb /usr/lib/jvm/java-7-sun/bin/jdb
jdk jhat /usr/lib/jvm/java-7-sun/bin/jhat
jdk jinfo /usr/lib/jvm/java-7-sun/bin/jinfo
jdk jmap /usr/lib/jvm/java-7-sun/bin/jmap
jdk jps /usr/lib/jvm/java-7-sun/bin/jps
jdk jrunscript /usr/lib/jvm/java-7-sun/bin/jrunscript
jdk jsadebugd /usr/lib/jvm/java-7-sun/bin/jsadebugd
jdk jstack /usr/lib/jvm/java-7-sun/bin/jstack
jdk jstat /usr/lib/jvm/java-7-sun/bin/jstat
jdk jstatd /usr/lib/jvm/java-7-sun/bin/jstatd
jdk native2ascii /usr/lib/jvm/java-7-sun/bin/native2ascii
jdk rmic /usr/lib/jvm/java-7-sun/bin/rmic
jdk schemagen /usr/lib/jvm/java-7-sun/bin/schemagen
jdk serialver /usr/lib/jvm/java-7-sun/bin/serialver
jdk wsgen /usr/lib/jvm/java-7-sun/bin/wsgen
jdk wsimport /usr/lib/jvm/java-7-sun/bin/wsimport
jdk xjc /usr/lib/jvm/java-7-sun/bin/xjc
plugin xulrunner-addons-javaplugin.so /usr/lib/jvm/java-7-sun/jre/plugin/i386/ns7/libjavaplugin_oji.so

说明，/usr/lib/jvm/.xxx.jinfo用于执行update-java-alternatives

６、执行update-java-alternatives

/usr/lib/jvm$ sudo update-java-alternatives -l
java-1.6.0-openjdk-i386 1061 /usr/lib/jvm/java-1.6.0-openjdk-i386
java-1.7.0-openjdk-i386 1051 /usr/lib/jvm/java-1.7.0-openjdk-i386
java-6-sun 63 /usr/lib/jvm/java-6-sun
java-7-sun 63 /usr/lib/jvm/java-7-sun
/usr/lib/jvm$ sudo update-java-alternatives -s java-7-sun
update-alternatives: 错误: 无 mozilla-javaplugin.so 的候选项。
update-alternatives: 错误: 无 xulrunner-addons-javaplugin.so 的候选项。
update-java-alternatives: jdk alternative does not exist: /usr/lib/jvm/java-7-sun/bin/HtmlConverter
update-alternatives: 错误: wsgen 的候选项 /usr/lib/jvm/java-7-sun/bin/wsgen 没有注册，不予设置。
update-alternatives: 错误: 无 xulrunner-addons-javaplugin.so 的候选项。

如果需要配置浏览器，可以参照oracle的文档：http://www.oracle.com/technetwork/java/javase/manual-plugin-install-linux-136395.html

转自：http://www.cnblogs.com/yondy/archive/2013/01/02/2842171.html