Step 1: Update Your System

Before installing Java, make sure your Ubuntu 22.04 system is up to date. Run the following command to update your package lists and upgrade existing packages:

sudo apt update && sudo apt upgrade

This ensures that all the packages on your system are up to date, which is important for both local and cloud hosting environments such as Windows VPS hosting UK.

Step 2: Install OpenJDK

OpenJDK is the open-source implementation of the Java Platform, Standard Edition. To install OpenJDK 11, run the following command:

sudo apt install openjdk-11-jdk

If you need OpenJDK 17 (the latest long-term support version), you can install it by running:

sudo apt install openjdk-17-jdk

After the installation, you can verify that Java has been installed correctly by checking the version:

java -version

OpenJDK is now installed, making your system ready for Java development and application deployment. This setup works for local environments or if you're deploying Java-based applications on Windows VPS servers.

Step 3: Install Oracle JDK

Oracle JDK is another popular version of Java, often preferred for enterprise-level applications. To install Oracle JDK on Ubuntu 22.04, follow these steps:

First, add the Oracle PPA to your system:

sudo add-apt-repository ppa:linuxuprising/java
sudo apt update
            

Next, install Oracle JDK 17 (the latest LTS version) with the following command:

sudo apt install oracle-java17-installer

Once the installation is complete, set Oracle JDK as the default version:

sudo apt install oracle-java17-set-default

Verify that Oracle JDK is installed by checking the version:

java -version

Oracle JDK is now installed and configured as the default Java version on your system, whether you're working locally or deploying applications on Windows Virtual Private Server hosting.

Step 4: Switch Between Java Versions

If you have multiple versions of Java installed on your system (for example, both OpenJDK and Oracle JDK), you can easily switch between them. To set the default Java version, use the following command:

sudo update-alternatives --config java

You will be presented with a list of installed Java versions. Enter the number corresponding to the version you want to use and press Enter.

This feature is especially useful when testing Java applications in different environments, whether hosted locally or on a VPS Windows Servers environment.

Step 5: Set JAVA_HOME Environment Variable

Some Java applications require the JAVA_HOME environment variable to be set. To set this, find the installation path of your Java version by running:

sudo update-alternatives --config java

Copy the installation path and add it to your ~/.bashrc file:

echo "export JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64" >> ~/.bashrc

Replace the path with your Java installation path. Then, reload your shell environment:

source ~/.bashrc

This will set the JAVA_HOME environment variable, which is essential for some development tools and applications, whether you’re working on a local machine or deploying on Windows VPS hosting UK.