How To Manually Install Oracle Java on Ubuntu

Introduction

Java is a programming technology originally developed by Sun Microsystems and later acquired by Oracle. Oracle Java is a proprietary implementation for Java that is free to download and use for commercial use, but not to redistribute, therefore it is not included in a officially maintained repository.

There are many reasons why you would want to install Oracle Java over OpenJDK. In this tutorial, we will not discuss the differences between the above mentioned implementations.

Assumptions

This tutorial assumes that you have an account with DigitalOcean, as well as a Droplet running Debian 7 or Ubuntu 12.04 or above. You will need root privileges (via sudo) to complete the tutorial.

You will need to know whether you are running a 32 bit or a 64 bit OS:

i46614161@i46614161:/usr/local/java/jdk1.8.0_05$ uname -m
i686

x86_64: 64 bit kernel

i686: 32 bit kernel

Downloading Oracle Java JDK

Using your web browser, go to the Oracle Java SE (Standard Edition) website and decide which version you want to install:

JDK: Java Development Kit. Includes a complete JRE plus tools for developing, debugging, and monitoring Java applications.

Server JRE: Java Runtime Environment. For deploying Java applications on servers. Includes tools for JVM monitoring and tools commonly required for server applications.

In this tutorial we will be installing the JDK Java SE Development Kit 8 x64 bits. Accept the license and copy the download link into your clipboard. Remember to choose the right tar.gz (64 or 32 bits). Use wget to download the archive into your server:

wget --header "Cookie: oraclelicense=accept-securebackup-cookie" http://download.oracle.com/otn-pub/java/jdk/8u5-b13/jdk-8u5-linux-i586.tar.gz[/code] 
Oracle does not allow downloads without accepting their license, therefore we needed to modify the header of our request. Alternatively, you can just download the compressed file using your browser and manually upload it using a SFTP/FTP client.

Always get the latest version from Oracle's website and modify the commands from this tutorial accordingly to your downloaded file.

Or U can visit the website directly and download the tar.gz file do not  visa the command .

Installing Oracle JDK
In this section, you will need sudoprivileges:

sudo


sudomkdir -p /usr/local/java 


cd /home/"your_user_name"/Downloads
sudocp -r jdk-8u5-linux-i586.tar.gz /usr/local/java/
cd /usr/local/java
sudotar xvzf jdk-8u5-linux-i586.tar.gz


Setting Oracle JDK as the default JVM
In our case, the java executable is located under /usr/local/java/jdk1.8.0_05/bin/java . To set it as the default JVM in your machine run:

 sudo update-alternatives --install /usr/bin/java java  /usr/local/java/jdk1.8.0_05/bin/java 100
sudoupdate-alternatives --install /usr/bin/javac javac  /usr/local/java/jdk1.8.0_05/bin/javac 100


sudoupdate-alternatives --install /usr/bin/javaws javaws  /usr/local/java/jdk1.8.0_05/bin/javaws 100


Verify your installation
Verify that java has been successfully configured by running:

update-alternatives --display java


update-alternatives --display javac


The output should look like this:

java - auto mode
link currently points to /usr/local/java/jdk1.8.0_05/bin/java
/usr/local/java/jdk1.8.0_05/bin/java - priority 100
Current 'best' version is '/usr/local/java/jdk1.8.0_05/bin/java'.


javac - auto mode
link currently points to /usr/local/java/jdk1.8.0_05/bin/javac
/usr/local/java/jdk1.8.0_05/bin/javac - priority 100
Current 'best' version is '/usr/local/java/jdk1.8.0_05/bin/javac'.


Another easy way to check your installation is:

java -version


After installation is complete, set  environment variables as follows

Edit the system Path file /etc/profile

sudogedit /etc/profile


Add following lines in end

JAVA_HOME=/usr/local/java/jdk1.8.0_05
PATH=$PATH:$HOME/bin:$JAVA_HOME/bin
export JAVA_HOME
export PATH


Note:The environment variables modifiy will active after you logout or reboot system .