Install Java in Linux

Install Java in Linux

Introduction
Java is a popular programming language that is widely used for developing various applications. To run Java applications on your Linux system, you need to install the Java Runtime Environment (JRE) or the Java Development Kit (JDK). In this documentation, we will guide you through the process of downloading and installing Java in Linux, specifically on the Ubuntu distribution.

Prerequisites
Before proceeding with the installation, make sure you have the following prerequisites:

1. An Ubuntu Linux system with administrative privileges (sudo access).
2. A working internet connection to download Java packages.

Step 1: Update Package List
First, we need to update the package list to ensure we get the latest available packages.

Open the terminal and execute the following command:

bash
sudo apt update

Step 2: Install Default Java Runtime (JRE)
Ubuntu usually comes with OpenJDK, which is an open-source implementation of the Java Platform. You can install the default JRE using the following command:

bash
sudo apt install default-jre

Step 3: Install Default Java Development Kit (JDK)
If you plan to develop Java applications, you need the JDK, which includes the JRE along with development tools. To install the default JDK, use the following command:

bash
sudo apt install default-jdk

Step 4: Verify Installation
To verify that Java has been successfully installed, you can check the version of Java:

For JRE:

bash
java -version

For JDK:

bash
javac -version

If installed correctly, the terminal will display the installed Java version.

Step 5: Set Java Environment Variables (Optional)
In some cases, you may need to set the JAVA_HOME and PATH environment variables to point to the Java installation directory. This step is essential if you plan to use Java for development purposes or running Java-based applications.

To set the environment variables, open the .bashrc file using a text editor:

bash
sudo nano ~/.bashrc

Add the following lines at the end of the file:

bash
export JAVA_HOME=/usr/lib/jvm/default-java
export PATH=$PATH:$JAVA_HOME/bin

Save and close the file. Then, apply the changes by running:

bash
source ~/.bashrc

Conclusion
Congratulations! You have successfully installed Java on your Ubuntu Linux system. You can now run Java applications or use the JDK for Java development.

Remember that Java versions might change over time, so it's always a good idea to refer to the official documentation or the package manager for the latest installation instructions.