Satish Chilukuri’s Blog 

Installing Java 8

By default, Debian repositories only have Open JDK and on Wheezy, the Open JDK version is the equivalent of Java 7. To get the latest Java 8, we need to install it manually. First download the Java 8 server JRE which comes with JVM monitoring tools. Or you could just download the Java 8 JDK which includes those monitoring tools and more. I prefer to install only the bare minimum setup that is necessary.

When manually installing software on Linux, it is recommended that it go into /opt directory. So unpack the JRE or JDK into /opt.

Create a symbolic link "java8" pointing to the JRE/JDK directory. This will make it easier when installing updates to the JRE/JDK. All Java dependent applications will refer to the symbolic link and when you do update the JRE/JDK, you don’t need to update the path to Java for all those applications. You just need to update the symbolic link.

cd /opt
sudo ln -s jdk1.8.0_25 java8

Add the Java bin directory to your PATH so that the Java commands are available to you. Edit your .profile file

vi ~/.profile

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