In this tutorial we will quickly setup java on linux centos,
We will be using the yum command to download the openjdk 1.8 and install
[vamshi@node01 ~]$ sudo yum install java-1.8.0-openjdk.x86_64
We have installed the java openjdk 1.8 and we can check the version using java -version
[vamshi@node01 ~]$ java -version openjdk version "1.8.0_252" OpenJDK Runtime Environment (build 1.8.0_252-b09) OpenJDK 64-Bit Server VM (build 25.252-b09, mixed mode)
We make use of the alternatives command in centos which lists if we have any other version of java installed on the machine, and then enabling the default java version on the system wide.
[vamshi@node01 ~]$ alternatives --list | grep java java auto /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.252.b09-2.el7_8.x86_64/jre/bin/java jre_openjdk auto /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.252.b09-2.el7_8.x86_64/jre jre_1.8.0 auto /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.252.b09-2.el7_8.x86_64/jre jre_1.7.0 auto /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.261-2.6.22.2.el7_8.x86_64/jre
[vamshi@node01 ~]$ sudo alternatives --config java There are 2 programs which provide 'java'. Selection Command ----------------------------------------------- * 1 java-1.8.0-openjdk.x86_64 (/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.252.b09-2.el7_8.x86_64/jre/bin/java) + 2 java-1.7.0-openjdk.x86_64 (/usr/lib/jvm/java-1.7.0-openjdk-1.7.0.261-2.6.22.2.el7_8.x86_64/jre/bin/java) Enter to keep the current selection[+], or type selection number: 1
This enabled openjdk1.8 to be the default version of java.
Setting JAVA_HOME path
In order to set the system JAVA_HOME path on the system we need to export this variable, for the obvious reasons of other programs and users using the classpath such as while using maven or a servlet container.
Now there are two levels we can setup the visibility of JAVA_HOME environment variable.
1. Setup JAVA_HOME for single user profile
We need to update the changes to the ~/.bash_profile
export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.252.b09-2.el7_8.x86_64/jre/bin/ PATH=$PATH:$JAVA_HOME export PATH
Now we need enforce the changes with reloading the .bash_profile with a simple logout and then login into the system or we can source the file ~/.bash_profile as follows:
[vamshi@node01 ~]$ source .bash_profile
Verifying the changes:
[vamshi@node01 ~]$ echo $PATH /usr/local/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/home/vamshi/.local/bin:/home/vamshi/bin:/home/vamshi/.local/bin:/home/vamshi/bin:/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.252.b09-2.el7_8.x86_64/jre/bin/
2. Setup JAVA_HOME for the system wide profile and available to all the users.
[vamshi@node01 ~]$ sudo sh -c "echo -e 'export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.252.b09-2.el7_8.x86_64/jre/bin/' > /etc/profile.d/java.sh"
This echo command writes the JAVA_HOME path to the system profile.d and creates a file java.sh which is read system wide level.
Ensure the changes are written to /etc/profile.d/java.sh
[vamshi@node01 ~]$ cat /etc/profile.d/java.sh export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.252.b09-2.el7_8.x86_64/jre/bin/
Now source to apply the changes immediately to the file /etc/profile.d/java.sh as follows
[vamshi@node01 ~]$ sudo sh -c ' source /etc/profile.d/java.sh '
Or login to the root account and run the source command
Ensure to run the env command
[vamshi@node01 ~]$ env | grep JAVA_HOME JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.252.b09-2.el7_8.x86_64/jre/bin/
How do I download and install Java on CentOS?
Install Java On CentOS
- Install OpenJDK 11. Update the package repository to ensure you download the latest software: sudo yum update. …
- Install OpenJRE 11. Java Runtime Environment 11 (Open JRE 11) is a subset of OpenJDK. …
- Install Oracle Java 11. …
- Install JDK 8. …
- Install JRE 8. …
- Install Oracle Java 12.
Is Java installed on CentOS?
OpenJDK, the open-source implementation of the Java Platform, is the default Java development and runtime in CentOS 7. The installation is simple and straightforward.
How do I install Java on Linux?
- Java for Linux Platforms
- Change to the directory in which you want to install. Type: cd directory_path_name. …
- Move the . tar. gz archive binary to the current directory.
- Unpack the tarball and install Java. tar zxvf jre-8u73-linux-i586.tar.gz. The Java files are installed in a directory called jre1. …
- Delete the . tar.
How do I install latest version of Java on CentOS?
To install OpenJDK 8 JRE using yum, run this command: sudo yum install java-1.8. 0-openjdk.
Where is java path on CentOS?
They usually reside in /usr/lib/jvm . You can list them via ll /usr/lib/jvm . The value you need to enter in the field JAVA_HOME in jenkins is /usr/lib/jvm/java-1.8.
How do I know if java is installed on CentOS 7?
- To check the Java version on Linux Ubuntu/Debian/CentOS:
- Open a terminal window.
- Run the following command: java -version.
- The output should display the version of the Java package installed on your system. In the example below, OpenJDK version 11 is installed.
Where is java path set in Linux?
Steps
- Change to your home directory. cd $HOME.
- Open the . bashrc file.
- Add the following line to the file. Replace the JDK directory with the name of your java installation directory. export PATH=/usr/java/<JDK Directory>/bin:$PATH.
- Save the file and exit. Use the source command to force Linux to reload the .
How do I install java 14 on Linux?
Installing OpenJDK 14
- Step 1: Update APT. …
- Step 2: Download and Install JDK Kit. …
- Step 3: Check Installed JDK Framework. …
- Step 4: Update Path to JDK (Optional) …
- Step 6: Set Up Environment Variable. …
- Step 7: Open Environment File. …
- Step 8: Save Your Changes.
How do I know where java is installed on Linux?
This depends a bit from your package system … if the java command works, you can type readlink -f $(which java) to find the location of the java command. On the OpenSUSE system I’m on now it returns /usr/lib64/jvm/java-1.6. 0-openjdk-1.6. 0/jre/bin/java (but this is not a system which uses apt-get ).
How do I install java 11 on Linux?
Installing the 64-Bit JDK 11 on Linux Platforms
- Download the required file: For Linux x64 systems: jdk-11. interim. …
- Change the directory to the location where you want to install the JDK, then move the . tar. …
- Unpack the tarball and install the downloaded JDK: $ tar zxvf jdk-11. …
- Delete the . tar.