Install Java 8 in Linux 64bit

Install Java 8 in Linux:

1. Before installing Java, make sure to first verify the version of installed Java.
[obiee@obiee12c oracle]$java -version
java version "1.7.0_75"
OpenJDK Runtime Environment (IcedTea 2.5.4) (7u75-2.5.4-2)
OpenJDK 64-Bit Server VM (build 24.75-b04, mixed mode)

It’s clear from the output above that the installed version of Java is OpenJDK 1.7.0_75.

2. Make a directory where you want to install Java. For global access (for all users) install it preferably in the directory /opt/java.
[obiee@obiee12c oracle]$ su
password
[root@obiee12c oracle]# mkdir /opt/java
[root@obiee12c oracle]# cd /opt/java

3. Now it’s time to download Java (JDK) 8u91 source tarball files for your system architecture by going to official Java download page.
For reference, we have provided the source tarball file-names, please select and download these below mentioned files only.
- jdk-8u91-linux-x64.tar.gz        [For 64-bit Systems]

[root@obiee12c oracle]# cd /opt/java
[root@obiee12c oracle]# wget --no-cookies --no-check-certificate --header "Cookie: gpw_e24=http%3A%2F%2Fwww.oracle.com%2F; oraclelicense=accept-securebackup-cookie" "http://download.oracle.com/otn-pub/java/jdk/8u91-b14/jdk-8u91-linux-x64.tar.gz"

4. Once file has been downloaded, you may extract downloaded file
[root@obiee12c oracle]# tar -zxvf jdk-8u91-linux-x64.tar.gz

5. Next, move to the extracted directory and use command update-alternatives to tell system where java and its executables are installed.
[root@obiee12c oracle]# cd jdk1.8.0_91/
[root@obiee12c oracle]# update-alternatives --install /usr/bin/java java /opt/java/jdk1.8.0_91/bin/java 100 
[root@obiee12c oracle]# update-alternatives --config java

There are 3 programs which provide 'java'.

  Selection    Command
-----------------------------------------------
*  1           /usr/lib/jvm/jre-1.7.0-openjdk.x86_64/bin/java
   2           /usr/lib/jvm/jre-1.6.0-openjdk.x86_64/bin/java
 + 3           /usr/java/jdk1.8.0_91/jre/bin/java

Enter to keep the current selection[+], or type selection number:

6. Tell system to update javac alternatives as:
[root@obiee12c oracle]#  update-alternatives --install /usr/bin/javac javac /opt/java/jdk1.8.0_91/bin/javac 100
[root@obiee12c oracle]# update-alternatives --config javac

There are 2 programs which provide 'javac'.

  Selection    Command
-----------------------------------------------
*+ 1           /usr/java/jdk1.8.0_91/bin/javac
   2           /opt/java/jdk1.8.0_45/bin/javac

Enter to keep the current selection[+], or type selection number:

7. Similarly, update jar alternatives as:
[root@obiee12c oracle]# update-alternatives --install /usr/bin/jar jar /opt/java/jdk1.8.0_91/bin/jar 100
[root@obiee12c oracle]# update-alternatives --config jar

There is 1 program that provides 'jar'.

  Selection    Command
-----------------------------------------------
*+ 1           /usr/java/jdk1.8.0_91/bin/jar

Enter to keep the current selection[+], or type selection number: 1
[root@obiee12c oracle]#

8. Now You may verify the Java version again, to confirm.
[root@obiee12c oracle]# java -version
java version "1.8.0_91"
Java(TM) SE Runtime Environment (build 1.8.0_91-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.91-b14, mixed mode)
[root@obiee12c oracle]#

Optional:
Setting up Java Environment Variables.

# export JAVA_HOME=/opt/java/jdk1.8.0_91/   
# export JRE_HOME=/opt/java/jdk1.8.0._91/jre    
# export PATH=$PATH:/opt/java/jdk1.8.0_91/bin:/opt/java/jdk1.8.0_91/jre/bin

If you are not using OpenJDK (open source implementation of java), you may remove it as:
# apt-get remove openjdk-*