JDK(Java Development Kit) 是 Java 语言的软件开发工具包(SDK)。
官方下载：http://www.oracle.com/technetwork/java/javase/downloads/index.html
安装JDK8 u152：
# mkdir /usr/local/java
# tar -zxf jdk-8u152-linux-x64.tar.gz -C /usr/local/java //解压
# vim /etc/profile //建议添加全局环境变量
export JAVA_HOME=/usr/local/java/jdk1.8.0_152
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib
export PATH=$PATH:${JAVA_HOME}/bin
# source /etc/profile //配置生效
# java -version
java version "1.8.0_152"
Java(TM) SE Runtime Environment (build 1.8.0_152-b16)
Java HotSpot(TM) 64-Bit Server VM (build 25.152-b16, mixed mode)# vim ~/.bashrc //添加本地环境变量（只对当前用户有效，无需重启）
export JAVA_HOME=/usr/local/java/jdk1.8.0_152
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib
export PATH=$PATH:${JAVA_HOME}/bin
# source ~/.bashrc //配置立即生效
