How to remove old version of Java and install new version

Question

I am working on a Linux box on which Java 1.7 is installed:

#java -version

java version "1.7.0_09-icedtea"

OpenJDK Runtime Environment (rhel-2.3.4.1.el6_3-x86_64)

OpenJDK 64-Bit Server VM (build 23.2-b09, mixed mode)

I need to install the jdk-8u45-linux-x64.tar.gz

So how can I remove this old one and install the new one?

Answer 1

To remove OpenJDK (the one you've already installed)

sudo apt-get purge openjdk-\*

Make a new directory for your new JDK

sudo mkdir -p /usr/local/java

Copy your file to the directory (you should be in that file path)

sudo cp -r jdk-8u45-linux-x64.tar.gz /usr/local/java/

Extract the file

sudo tar xvzf jdk-8u45-linux-x64.tar.gz

You should add this to your PATH now. To do that:

a. Open /etc/profile : sudo gedit /etc/profile

b. Scroll down (the end) and add the trail where your jdk was installed

JAVA_HOME=/usr/local/java/jdk1.8.0_45 PATH=$PATH:$HOME/bin:$JAVA_HOME/bin export JAVA_HOME export PATH

Save and exit

Inform your Linux system where your Oracle Java JDK/JRE is found .

a. Notify the system that Oracle Java JRE is out there to be used

sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jdk1.8.0_45/bin/java" 1

b. Notify the system that Oracle Java JDK is out there to be used

sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/local/java/jdk1.8.0_45/bin/javac" 1

c. Notify the system that Oracle Java Web start is out there to be used

sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/local/java/jdk1.8.0_20/bin/javaws" 1

Inform the Linux system that a Oracle Java JDK/JRE must be in the default Java.

a. You need to set the java runtime environment for your system

sudo update-alternatives --set java /usr/local/java/jdk1.8.0_45/bin/java

b. Set the javac compiler for the system

sudo update-alternatives --set javac /usr/local/java/jdk1.8.0_45/bin/javac

c. Set Java Web start for the system

sudo update-alternatives --set javaws /usr/local/java/jdk1.8.0_20/bin/javaws

Reload your system wide PATH

source /etc/profile

Check the new version and you're done!

java -version

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