linux下JDK安装安装过程

1.下载jdk-6u20-linux-i586-rpm.bin 拷贝到/usr/local/目录下

2.进入 cd /usr/local/

3.增加执行权限  chmod +x jdk-6u20-linux-i586-rpm.bin

4.执行安装命令
   ./jdk-6u20-linux-i586-rpm.bin
   此时会生成文件jdk-6u20-linux-i586.rpm，同样给所有用户添加可执行的权限

    #chmod +x jdk-6u20-linux-i586.rpm

5.安装程序
#rpm -ivh jdk-6u20-linux-i586.rpm

6.安装完成,查看jdk的安装目录,为  /usr/java/jdk1.6.0_20

7.设置JDK环境变量。

#vi /etc/profile

添加如下内容:

export JAVA_HOME=/usr/java/jdk1.6.0_20

export JRE_HOME=$JAVA_HOME/jre

export PATH=$PATH:/usr/java/jdk1.6.0_20/bin

export   CLASSPATH=.:/usr/java/jdk1.6.0_20/lib:/usr/java/jdk1.6.0_20/jre/lib


8.在终端使用echo命令检查环境变量设置情况。

#echo $JAVA_HOME

#echo $CLASSPATH

#echo $PATH

9.检查JDK是否安装成功。

#java -version

10.如果看到JVM版本及相关信息，即安装成功！



卸载linux中已经安装的jdk

卸载步骤：

[root@localhost local]# rpm -qa|grep jdk
jdk-1.6.0_21-fcs.i586
[root@localhost local]# rpm -e jdk-1.6.0_21-fcs.i586

[root@localhost local]# rpm -qa|grep java
sun-javadb-core-10.5.3-0.2.i386
sun-javadb-docs-10.5.3-0.2.i386
sun-javadb-demo-10.5.3-0.2.i386
java-1.5.0-gcj-1.5.0.0-29.fc12.i686


[root@localhost local]# rpm -e java-1.5.0-gcj-1.5.0.0-29.fc12.i686
error: Failed dependencies:
        java-gcj-compat >= 1.0.43 is needed by (installed) lucene-0:2.3.1-5.5.fc12.i686
        java-gcj-compat is needed by (installed) xml-commons-apis-0:1.3.04-3.5.fc12.i686
        java-gcj-compat >= 1.0.70 is needed by (installed) sinjdoc-0.5-9.fc12.i686
        java-gcj-compat is needed by (installed) xalan-j2-0:2.7.0-9.5.fc12.i686
        java-gcj-compat is needed by (installed) jdom-0:1.0-7.5.fc12.i686
        java-gcj-compat is needed by (installed) java_cup-1:0.10k-3.i686
        jaxp_parser_impl is needed by (installed) xalan-j2-0:2.7.0-9.5.fc12.i686
        jaxp_parser_impl is needed by (installed) saxon-0:6.5.5-3.3.fc12.noarch
        jre >= 1.5.0 is needed by (installed) openoffice.org-ure-1:3.1.1-19.14.fc12.i686

有很多依赖关系，不让卸载，用 rpm -e --nodeps 卸载就行了

[root@localhost local]# rpm -e --nodeps java-1.5.0-gcj-1.5.0.0-29.fc12.i686