java insall & setting (1.6 / 1.7 /1.8)

Java Change

sudo add-apt-repository ppa:webupd8team/java

sudo apt-get update

sudo apt-get install oracle-java6-installer

1. sudo add-apt-repository ppa:openjdk-r/ppa
2. sudo apt-get update
3. sudo apt-get install openjdk-8-jdk