Introduction

• This document provides the steps on how to upgrade Java from version 8 to 11

 

Steps to install OpenJDK 11

Make sure you have the required repositories configured in the server and are up to date

1. Check the current Java version using the command

Java –version

 

  2. Install Java Development Kit using the command

sudo yum install java-11-openjdk-devel

 

3. The package OpenJRE is part of OpenJDK, so this needs to be installed using the command

sudo yum install java-11-openjdk

 

Steps to Oracle JDK11

Oracle JDK needs to be downloaded as .rpm from its download URL Oracle JDK 11

1. Copy the rpm file to the server
2. Run command

rpm –ivh jdk-11.0.20_linux-x64_bin.rpm

 

Set the default Java version to JDK11

Now you have two Java versions running, on the server and need to have the latest to be pointing to the application

1. Run the below command to check the installed versions

sudo alternatives --config java

 

2. The above example shows two selections. 1 for (Java 11) and 2 for (Java 8), In order to change the default to Java 11 type the value as 1 and hit Enter button

 

Set JAVA_HOME environment variable

The JAVA_HOME environment variable points to the file system location where the JDK or JRE was installed, it helps applications access the Java installation path.

 

1. Run the below command to check the installed path of Java on the server

sudo alternatives --config java

 

     2. Add the path in .bash_profile using an editor

vim .bash_profile

 

    3. Add the below line at the bottom

JAVA_HOME=”<java-install-path>”

In this example it is

 

JAVA_HOME=” /usr/lib/jvm/java-11-openjdk-11.0.20.0.8-1.el7_9.x86_64/bin/java”