linux jdk静默安装

#下载&解压mkdir /opt/java/cd /opt/java/wget http://download.oracle.com/otn-pub/java/jdk/7u79-b15/jdk-7

#下载&解压

mkdir /opt/java/cd  /opt/java/wget  http://download.oracle.com/otn-pub/java/jdk/7u79-b15/jdk-7u79-linux-x64.tar.gztar xvf jdk-7u79-linux-x64.tar.gz

1.通过软连接

ln -s   /opt/java/jdk1.7.0_79/bin/java /usr/bin/javaln -s   /opt/java/jdk1.7.0_79/bin/javac /usr/bin/javac--去掉软连接 rm /usr/bin/java

2.通过配置 /etc/profile 对所有用户有效

vi /etc/profileJAVA_HOME=/opt/java/jdk1.7.0_79/PATH=$JAVA_HOME/bin:$PATHCLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jarexport JAVA_HOMEexport PATHexport CLASSPATH

3.修改~/.bashrc文件（该方法修改后只对当前用户有效，对该用户的所有shell都有效）

vi  ~/.bashrcJAVA_HOME=/opt/java/jdk1.7.0_79/PATH=$JAVA_HOME/bin:$PATHCLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jarexport JAVA_HOMEexport PATHexport CLASSPATH