Installing Java 7 on Ubuntu

Question

to install java I have always used the classic way from the terminal. I would like to install java manually. I placed the folder of the JDK on the desk and I set environment

Answer 1

flup's answer is the best but it did not work for me completely. I had to do the following as well to get it working:

1. export JAVA_HOME=/usr/lib/jvm/java-7-oracle/jre/
2. chmod 777 on the folder
3. ./gradlew build - Building Hibernate