jdk安装

ubuntu

以 JDK 1.8.0_152 为例

• 下载安装包

下载地址 : http://www.oracle.com/technetwork/java/javase/downloads/index.html

上传： rz  jdk-8u152-linux-x64.tar.gz 

• 解压缩并移动到指定目录 

解压缩     tar -zxvf jdk-8u152-linux-x64.tar.gz 
创建目录     mkdir -p /usr/local/java 
移动安装包     mv jdk1.8.0_152/ /usr/local/java/ 
设置所有者     chown -R root:root /usr/local/java/ 

• 配置环境变量 

1）配置系统环境变量 
nano /etc/environment 
添加如下语句 
PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games"
export JAVA_HOME=/usr/local/java/jdk1.8.0_152
export JRE_HOME=/usr/local/java/jdk1.8.0_152/jre
export CLASSPATH=$CLASSPATH:$JAVA_HOME/lib:$JAVA_HOME/jre/lib 
2）配置用户环境变量 
nano /etc/profile 
添加如下语句 
if [ "$PS1" ]; then
  if [ "$BASH" ] && [ "$BASH" != "/bin/sh" ]; then
    # The file bash.bashrc already sets the default PS1.
    # PS1='\h:\w\$ '
    if [ -f /etc/bash.bashrc ]; then
      . /etc/bash.bashrc
    fi
  else
    if [ "`id -u`" -eq 0 ]; then
      PS1='# '
    else
      PS1='$ '
    fi
  fi
fi

export JAVA_HOME=/usr/local/java/jdk1.8.0_152
export JRE_HOME=/usr/local/java/jdk1.8.0_152/jre
export CLASSPATH=$CLASSPATH:$JAVA_HOME/lib:$JAVA_HOME/jre/lib
export PATH=$JAVA_HOME/bin:$JAVA_HOME/jre/bin:$PATH:$HOME/bin
 
if [ -d /etc/profile.d ]; then
  for i in /etc/profile.d/*.sh; do
    if [ -r $i ]; then
      . $i
    fi
  done
  unset i
fi 

• 使用户环境变量生效 

source /etc/profile 

• 配置软连接 

sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jdk1.8.0_152/jre/bin/java" 1 
sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/local/java/jdk1.8.0_152/bin/javac" 1 
sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/local/java/jdk1.8.0_152/jre/bin/javaws" 1 
sudo update-alternatives --set java /usr/local/java/jdk1.8.0_152/jre/bin/java 
sudo update-alternatives --set javac /usr/local/java/jdk1.8.0_152/bin/javac 
sudo update-alternatives --set javaws /usr/local/java/jdk1.8.0_152/jre/bin/javaws 

• 测试是否安装成功 

root@UbuntuBase:/usr/local/java# java -version
java version "1.8.0_152"
Java(TM) SE Runtime Environment (build 1.8.0_152-b16)
Java HotSpot(TM) 64-Bit Server VM (build 25.152-b16, mixed mode) 

• 为其他用户更新用户环境变量 

su lusifer
source /etc/profile

---

 

centos

卸载openjdk
rpm -qa | grep jdk
rpm -e --nodeps java-1.7.0-openjdk-xxxxx

• 安装

mkdir /root/develop
rz  jdk-8u211-linux-x64.tar.gz
tar zxvf jdk-8u211-linux-x64.tar.gz
mkdir /usr/local/java
cp -r  jdk-xxx /usr/local/java 

• 环境变量

vim /etc/profile
#set java enviroment
JAVA_HOME=/usr/local/java/jdkXXX
JRE_HOME=/usr/local/java/jdkXXX/jre
CLASS_PATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME JRE_HOME CLASS_PATH PATH

• 使环境变量生效 

source /etc/profile

• 验证

java -vsersion