Ubuntu 16.04 Installation OpenJDK 1.7

Because compiling Android source code requires openjdk1.7.x version. Ubuntu 16.04 comes with a 1.8.X version of OPENJDK.

sudo apt-get install openjdk-7-jre or sudo apt-get install OPENJDK-7-JDK

If it appears

There is no available package openjdk-7-jdk, but it is referenced by other packages.

This may mean that the missing package may have been discarded, or it could only be found in other publishing sources

E: Package OPENJDK-7-JDK No installable candidate

You can install the 1.7.X version according to the operation

sudo add-apt-repository ppa:openjdk-r/ppa  sudo apt-get update   sudo apt-get install openjdk-7-jdk 如果安装成功之后还是不能用可能不有多个版本，选的不对

sudo update-alternatives--config javasudo update-alternatives--config Javac pick the right version

Ubuntu 16.04 Installation OpenJDK 1.7