Ubuntu 14.04 安装 OpenJDK

1. Add OpenJDK PPA

sudo add-apt-repository ppa:openjdk-r/ppa

2. Update Package Cache

sudo apt-get update 

3. Install OpenJDK 8

sudo apt-get install openjdk-8-jdk

4. Set Default Java

sudo update-alternatives --config java
sudo update-alternatives --config javac
sudo update-alternatives --config javadoc

5. Check Current Version

java -version