封装jdk8到ubuntu:18.04

需要在docker里跑Spring Boot框架，搭建个基于ubuntu:18.04的java环境。

1. 拉取镜像及下载jdk压缩包。$sudo docker pull ubuntu:18.04，到存储服务器上找了个java包jdk-8u141-linux-x64.tar.gz

2. 使用Dockerfile来build新的镜像。

$ cd java_api

$ vim Dockerfile ,内容如下：

FROM ubuntu:18.04

ADD jdk-8u141-linux-x64.tar.gz /usr/local/java

ENV JAVA_HOME /usr/local/java/jdk1.8.0_141

ENV JRE_HOME /usr/local/java/jdk1.8.0_141/jre

ENV CLASSPATH $JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar

ENV PATH $PATH:$JAVA_HOME/bin

3. 构建镜像

$ docker build -t ubuntu-jdk8:18.04 .

Sending build context to Docker daemon  425.6MB

Step 1/6 : FROM ubuntu:18.04

 ---> 775349758637

Step 2/6 : ADD jdk-8u141-linux-x64.tar.gz /usr/local/java

 ---> 9a7c38f07159

Step 3/6 : ENV JAVA_HOME /usr/local/java/jdk1.8.0_141

 ---> Running in 9469e2781002

Removing intermediate container 9469e2781002

 ---> 652feae84944

Step 4/6 : ENV JRE_HOME /usr/local/java/jdk1.8.0_141/jre

 ---> Running in 9f8a3dcdf7db

Removing intermediate container 9f8a3dcdf7db

 ---> 6476d0827f65

Step 5/6 : ENV CLASSPATH $JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar

 ---> Running in 92991b289ec8

Removing intermediate container 92991b289ec8

 ---> e573a21578d1

Step 6/6 : ENV PATH $PATH:$JAVA_HOME/bin

 ---> Running in c4bebc8e2c72

Removing intermediate container c4bebc8e2c72

 ---> 7cc092532b01

Successfully built 7cc092532b01

Successfully tagged ubuntu-jdk8:18.04

4. 验证

$ docker run -it --name test ubuntu-jdk8:18.04

root@7dbbb1ee96b1:/# which java

/usr/local/java/jdk1.8.0_141/bin/java

root@7dbbb1ee96b1:/# java -version

java version "1.8.0_141"

Java(TM) SE Runtime Environment (build 1.8.0_141-b15)

Java HotSpot(TM) 64-Bit Server VM (build 25.141-b15, mixed mode)

结束。