Linux下JDK的卸载
判断JDK是否安装
执行命令:Java -version
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which java(查看JDK的安装路径)
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rm -rf JDK地址(卸载JDK) rm -rf /usr/local/jdk1.8.0_212/bin/java
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查看是否卸载完毕
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vi命令编辑文件 vi /etc/profile
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删除配置的环境变量,
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至此JDK卸载完毕。
JDK安装
上传JDK安装包
说明:将JDK安装包上传到指定文件目录下/usr/local下
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解压JDK文件
命令: tar -xvf jdk-7u51-linux-x64.tar.gz
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配置环境变量
说明:修改Linux系统中环境变量需要修改/etc/profile文件
命令:vim /etc/profile
配置文件变量
#set java envJAVA_HOME=/usr/local/src/jdk1.8.0_212JAVA_BIN=/usr/local/src/jdk1.8.0_212/binPATH=$JAVA_HOME/bin:$PATHCLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jarexport JAVA_HOME JAVA_BIN PATH CLASSPATH
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环境变量生效:
source /etc/profile
检测JDK是否生效
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