Installing java runtime on linux

Install the Java Runtime Environment

The Java Runtime Environment (JRE) is required to run Java programs. Nowadays there are many JRE packages available from a variety of projects and companies, but the two most popular on Ubuntu are OpenJDK and Oracle HotSpot. Using one package over the other should not create any functional difference in most applications; however, some prefer OpenJDK over Oracle HotSpot as the former does not contain closed-source components, has a much clearer licensing and support policy, and is maintained as part of the Ubuntu archive, with easier installation and upgrades.

In this guide, we’ll be going through the installation of both JRE packages. Of course, you generally only need to pick the one that best suits your needs and preferences.

What you’ll learn

What you’ll need

That’s all you need. If you have that, let’s proceed to the next step!

2. Installing OpenJDK JRE

With new versions of Java released every 6 months, there are multiple versions available for use. Nowadays, Java 11 is the current Long Term Support (LTS) version, but Java 8 is still widely used. Moreover, the non LTS versions of Java are bringing a steady stream of innovation into the language, and also see some adoption.

Ubuntu offers the default-jre package, which is regularly updated to ship the latest version of the current OpenJDK JRE in Long Term Support (LTS). The default-jre is an excellent choice for most situations, thanks to the outstanding track of backwards compatibility of the Java Virtual Machine.

(Alternatively, you may opt to use a specific Java version, using for example the openjdk-11-jre package; as updates are released for that version of the Java Virtual Machine, that packages will be updated, allowing you to stick to the latest and greatest update of one specific version of the Java language.)

To install the OpenJDK JRE, we run:

sudo apt install default-jre 

We can check if OpenJDK JRE was properly installed by running:

It should output the following:

openjdk version "11.0.11" 2021-04-20 OpenJDK Runtime Environment (build 11.0.11+9-Ubuntu-0ubuntu2) OpenJDK 64-Bit Server VM (build 11.0.11+9-Ubuntu-0ubuntu2, mixed mode) 

(Although the output may change in the future as new Java versions are promoted to LTS status, or the current LTS version receives updates.)

In the next step we’ll install Oracle HotSpot JRE.

3. Installing Oracle HotSpot JRE

Downloading the Oracle HotSpot JRE binaries

Download JRE binaries in .tar.gz (tarball) by heading over to their website. An Oracle account is needed to download the Oracle HotSpot JRE.

Oracle does not currently offer JRE packages for Java 11 or above from their website so, for this tutorial, we will use the Oracle HotSpot JRE version to be 8u291 (Java 8, update 291).

Installing

Create a directory to install JRE in with:

Move the JRE binaries into the directory:

sudo mv jre-8u291-linux-x64.tar.gz /usr/local/java 

Go into the install directory:

sudo tar zxvf jre-8u291-linux-x64.tar.gz 

Post-installation steps

To save space, delete the tarball by running:

sudo rm jre-8u291-linux-x64.tar.gz 

Let the system know where JRE is installed:

sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jre1.8.0_291/bin/java" 1 

After that’s done, check the installation by running:

It should output the following:

java version "1.8.0_291" Java(TM) SE Runtime Environment (build 1.8.0_291-b10) Java HotSpot(TM) 64-Bit Server VM (build 25.291-b10, mixed mode) 

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7 JRE Installation for Linux Platforms

This page describes JRE for Linux system requirements and gives installation instructions for several JRE-Linux combinations.

This page contains these topics:

See «JDK 8 and JRE 8 Installation Start Here» for general information about installing JDK 8 and JRE 8.

For information on enhancements to JDK 8 that relate to the installer, see «Installer Enhancements in JDK 8».

System Requirements

See http://www.oracle.com/technetwork/java/javase/certconfig-2095354.html for information about supported platforms, operating systems, and browsers.

On a 64-bit system, you can download either the 64-bit or the 32-bit version of the Java platform. However, if you are using a 32-bit browser and you want to use the plugin, then you need to install the 32-bit version of the Java platform. To determine which version of Firefox you are running, launch the application, and select the menu item Help -> About Mozilla Firefox. At the bottom of the window is a version string line that contains either «Linux i686» (32-bit) or «Linux x86_64» (64-bit). To setup the Java plugin, see «Manual Installation and Registration of Java Plugin for Linux».

JRE 8 Installation Instructions

This topic contains these topics:

Installation Instruction Notation and Files

For instructions containing the notation version , substitute the appropriate JRE update version number. For example, if you are installing update JRE 8 update release 2, the following string representing the name of the bundle:

jre-8uversion-linux-i586.tar.gz

Note that, as in the preceding example, the version number is sometimes preceded with the letter u , for example, 8u2 , and sometimes it is preceded with an underbar, for example, jre1.8.0_02 .

The following table lists the options and instructions for downloading the JRE 8 release for a Linux platform.

Download File and Instructions	Architecture	Who Can Install
jre-8u version -linux-x64.tar.gz «Installation of the 64-bit JRE on Linux Platforms»	64-bit	anyone
j re-8u version -linux-i586.tar.gz «Installation of the 32-bit JRE on Linux Platforms»	32-bit	anyone
jre-8u version -linux-x64.rpm «Installation of the 64-bit JRE on RPM-based Linux Platforms»	64-bit RPM-based Linux	root
jre-8u version -linux-i586.rpm «Installation of the 32-bit JRE on RPM-based Linux Platforms»	32-bit RPM-based Linux	root

JDK 7u6 and later releases include JavaFX SDK (version 2.2 or later). The JavaFX SDK and Runtime are installed and integrated into the standard JDK directory structure.

Installation of the 64-bit JRE on Linux Platforms

This procedure installs the Java Runtime Environment (JRE) for 64-bit Linux, using an archive binary file ( .tar.gz ).

These instructions use the following file:

jre-8uversion-linux-x64.tar.gz

1. Download the file. Before the file can be downloaded, you must accept the license agreement. The archive binary can be installed by anyone (not only root users), in any location that you can write to. However, only the root user can install the JDK into the system location.
2. Change directory to the location where you would like the JDK to be installed, then move the .tar.gz archive binary to the current directory.
3. Unpack the tarball and install the JRE.

% tar zxvf jre-8uversion-linux-x64.tar.gz

Installation of the 64-bit JRE on RPM-based Linux Platforms

This procedure installs the Java Runtime Environment (JRE) for 64-bit RPM-based Linux platforms, such as Red Hat and SuSE, using an RPM binary file ( .rpm ) in the system location. You must be root to perform this installation.

These instructions use the following file:

jre-8uversion-linux-x64.rpm

1. Download the file. Before the file can be downloaded, you must accept the license agreement.
2. Become root by running su and entering the super-user password.
3. Uninstall any earlier installations of the JDK packages.

# rpm -ivh jre-8uversion-linux-x64.rpm

# rpm -Uvh jre-8uversion-linux-x64.rpm

Installation of the 32-bit JRE on Linux Platforms

This procedure installs the Java Runtime Environment (JRE) for 32-bit Linux, using an archive binary file ( .tar.gz ).

These instructions use the following file:

jre-8uversion-linux-i586.tar.gz

1. Download the file. Before the file can be downloaded, you must accept the license agreement. The archive binary can be installed by anyone (not only root users), in any location that you can write to. However, only the root user can install the JRE into the system location.
2. Change directory to the location where you would like the JRE to be installed, then move the .tar.gz archive binary to the current directory.
3. Unpack the tarball and install the JRE.

% tar zxvf jre-8uversion-linux-i586.tar.gz

Installation of the 32-bit JRE on RPM-based Linux Platforms

This procedure installs the Java Runtime Environment (JRE) for 32-bit RPM-based Linux platforms, such as Red Hat and SuSE, using an RPM binary file ( .rpm ) in the system location. You must be root to perform this installation.

These instructions use the following file:

jre-8uversion-linux-i586.rpm

1. Download the file. Before the file can be downloaded, you must accept the license agreement.
2. Become root by running su and entering the super-user password.
3. Uninstall any earlier installations of the JRE packages.

# rpm -ivh jre-8uversion-linux-i586.rpm

# rpm -Uvh jre-8uversion-linux-i586.rpm

Installation of Public Key on RPM-based Linux Platforms

Since JDK version 8, the JRE RPMs are signed with OL keys. Installation of these RPMs on Linux distributions other than OL gives a warning message indicating that security validation of the package fails. This indicates that the public key used to sign this RPM needs to be installed in the system. A sample warning message and the public key installation steps are as follows:

Sample Warning Message

jdk-8u281-ea-bin-b03-linux-amd64-20_oct_2020.rpm: Header V3 RSA/SHA256 Signature, key ID ec551f03: NOKEY

Installation Steps

1. Download the key file from https://yum.oracle.com/RPM-GPG-KEY-oracle-ol7 using the following command: wget https://yum.oracle.com/RPM-GPG-KEY-oracle-ol7
2. Install the key using the following command: sudo rpm —import RPM-GPG-KEY-oracle-ol7

General Installation Notes

This topic describes general installation topics.

Root Access

Installing the software automatically creates a directory called jre1.8.0_ version . Note that if you choose to install the Java SE Runtime Environment into system-wide location such as /usr/jre , you must first become root to gain the necessary permissions. If you do not have root access, simply install the Java SE Runtime Environment into your home directory, or a subdirectory that you have permission to write to.

Overwriting Files

If you install the software in a directory that contains a subdirectory named jre 1.8.0_ version , the new software overwrites files of the same name in that jre 1.8.0_ version directory. Rename the old directory if it contains files you want to keep.

System Preferences

By default, the installation script configures the system such that the backing store for system preferences is created inside the JRE’s installation directory. If the JRE is installed on a network-mounted drive, it and the system preferences can be exported for sharing with Java runtime environments on other machines.

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