centos卸載openjdk及安裝sun jdk

• 查看已安裝的jdk版本

[root@localhost o2o]# java -version
java version "1.6.0_20"
OpenJDK Runtime Environment (IcedTea6 1.9.7) (rhel-1.39.1.9.7.el6-x86_64)
OpenJDK 64-Bit Server VM (build 19.0-b09, mixed mode)

• 卸載openjdk

        

1.查看版本信息
[root@localhost o2o]# rpm -qa | grep java
java-1.6.0-openjdk-1.6.0.0-1.39.1.9.7.el6.x86_64
tzdata-java-2011g-1.el6.noarch

2.卸載openjdk
[root@localhost o2o]# rpm -e --nodeps java-1.6.0-openjdk-1.6.0.0-1.39.1.9.7.el6.x86_64

3.查看是否還存在
[root@localhost o2o]# java -version
-bash: /usr/bin/java: 沒有那個文件或目錄

• 安裝sun jdk

[root@localhost local]# chmod a+x jdk-6u30-linux-x64.bin 
[root@localhost local]# ./jdk-6u30-linux-x64.bin

• 配置環境變量

1. 使用vim編輯添加如下信息
[root@localhost local]# vim /etc/profile
export JAVA_HOME=/usr/local/jdk1.6.0_30
export CLASSPATH=.:$JAVA_HOME/jre/lib/rt.jar:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export PATH=$PATH:$JAVA_HOME/bin

2.使修改生效
[root@localhost jdk1.6.0_30]# . /etc/profile

3.查看
[root@localhost local]# java -version
java version "1.6.0_30"
Java(TM) SE Runtime Environment (build 1.6.0_30-b12)
Java HotSpot(TM) 64-Bit Server VM (build 20.5-b03, mixed mode)