debian9安装jdk1.8

//先跟新可用安装信息

apt-get update

//查看可以安装的jdk版本

apt-cache search jdk

//会显示如下内容：

         openjdk-8-dbg - Java runtime based on OpenJDK (debugging symbols)
         openjdk-8-demo - Java runtime based on OpenJDK (demos and examples)
         openjdk-8-doc - OpenJDK Development Kit (JDK) documentation
         openjdk-8-jdk - OpenJDK Development Kit (JDK)
         openjdk-8-jdk-headless - OpenJDK Development Kit (JDK) (headless)
         openjdk-8-jre - OpenJDK Java runtime, using Hotspot JIT
         openjdk-8-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
         openjdk-8-jre-zero - Alternative JVM for OpenJDK, using Zero/Shark
         openjdk-8-source - OpenJDK Development Kit (JDK) source files
         openjdk-8-jre-dcevm - Alternative VM for OpenJDK 8 with enhanced class redefinition

//选择需要安装的版本:

apt-get install openjdk-8-jdk

//等待安装完成，验证是否完成安装

java -version

//显示如下信息，确定完成安装。

         openjdk version "1.8.0_232"
         OpenJDK Runtime Environment (build 1.8.0_232-8u232-b09-1~deb9u1-b09)
         OpenJDK 64-Bit Server VM (build 25.232-b09, mixed mode)