Installing Java on a Dedicated Server (CentOS, AlmaLinux, Debian, Ubuntu)

How to install Java on a Dedicated Server

For CentOS 9 / AlmaLinux 9

1. Open terminal.
   
2. Update the system:
   sudo dnf update
   
3. Install Java 17 runtime:
   sudo dnf install java-17-openjdk
   
4. For JDK (development kit):
   sudo dnf install java-17-openjdk-devel
   

For Debian 10 / 11 / 12

1. Update package list:
   sudo apt update
   
2. Install Java 17:
   sudo apt install openjdk-17-jdk
   

Other available packages:

• openjdk-11-jdk
  
• openjdk-21-jdk
  

For Ubuntu 20.04 / 22.04 / 24.04

1. Update the system:
   sudo apt update
   
2. Install recommended version:
   sudo apt install default-jdk
   Or a specific version:
   sudo apt install openjdk-17-jdk
   

Verify Installation

• Check Java version:
  java -version
  
• Check compiler:
  javac -version
  

Set JAVA_HOME Variable

1. Get the Java path:
   readlink -f $(which java)
   
2. Open environment file:
   sudo nano /etc/environment
   
3. Add the line:
   JAVA_HOME=”/usr/lib/jvm/java-17-openjdk-…”
   
4. Apply changes:
   source /etc/environment
   
5. Confirm:
   echo $JAVA_HOME
   

Optional: Oracle JDK (Manual Installation)

1. Download the .tar.gz archive from Oracle.
   
2. Extract to /opt/java/.
   
3. Manually setJAVA_HOME and add to PATH.
   

Summary Table

OS	Installation Command
CentOS / Alma 9	dnf install java-17-openjdk
Debian 10–12	apt install openjdk-17-jdk
Ubuntu 20.04+	apt install default-jdk or openjdk-17

Order a dedicated server here.