shell脚本自动安装jdk的方法示例

#!/bin/bash

jdkTargz="/opt/jdk-8u221-linux-x64.tar.gz"

# 检查原先是否已配置java环境变量
checkExist(){
 jdk1=$(grep -n "export JAVA_HOME=.*" /etc/profile | cut -f1 -d':')
    if [ -n "$jdk1" ];then
        echo "JAVA_HOME已配置，删除内容"
        sed -i "${jdk1}d" /etc/profile
    fi
 jdk2=$(grep -n "export CLASSPATH=.*\$JAVA_HOME.*" /etc/profile | cut -f1 -d':')
    if [ -n "$jdk2" ];then
        echo "CLASSPATH路径已配置，删除内容"
        sed -i "${jdk2}d" /etc/profile
    fi
 jdk3=$(grep -n "export PATH=.*\$JAVA_HOME.*" /etc/profile | cut -f1 -d':')
    if [ -n "$jdk3" ];then
        echo "PATH-JAVA路径已配置，删除内容"
        sed -i "${jdk3}d" /etc/profile
    fi
}

# 查询是否有jdk.tar.gz
if [ -e $jdkTargz ];
then

echo "— — 存在jdk压缩包 — —"
 echo "正在解压jdk压缩包..."
 tar -zxvf /opt/jdk-8u221-linux-x64.tar.gz -C /opt
 if [ -e "/opt/install/java" ];then
 echo "存在该文件夹，删除..."
 rm -rf /opt/install/java
 fi
 echo "---------------------------------"
 echo "正在建立jdk文件路径..."
 echo "---------------------------------"
 mkdir -p /opt/install/java/
 mv /opt/jdk1.8.0_221 /opt/install/java/java8
 # 检查配置信息
 checkExist 
 echo "---------------------------------"
 echo "正在配置jdk环境..."
 sed -i '$a export JAVA_HOME=/opt/install/java/java8' /etc/profile
 sed -i '$a export CLASSPATH=.:$JAVA_HOME/jre/lib/rt.jar:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar' /etc/profile
 sed -i '$a export PATH=$PATH:$JAVA_HOME/bin' /etc/profile
 echo "---------------------------------"
 echo "JAVA环境配置已完成..."
 echo "---------------------------------"
  echo "正在重新加载配置文件..."
  echo "---------------------------------"
  source /etc/profile
  echo "配置版本信息如下："
  java -version
else
 echo "未检测到安装包，请将安装包放到/opt目录下"
fi