Linux Apps Tutorials - Herong's Tutorial Examples - v1.03, by Herong Yang
Upgrade OpenJDK on CentOS
This section provides a tutorial example on how to upgrade OpenJDK on CentOS 8 systems using package manager 'dnf/yum' and symbolic link manager 'update-alternatives' symbolic links for 'java/javac' command.
If you want run Java applications that requires newer versions than Java 1.8 on CentOS 8 systems, you can upgrade OpenJDK to a newer version by following this tutorial.
1. Search for available OpenJDK packages. The output shows that the latest version is OpenJDK 17.
herong$ dnf search openjdk java-1.8.0-openjdk.x86_64 : OpenJDK 8 Runtime Environment java-1.8.0-openjdk-devel.x86_64 : OpenJDK 8 Development Environment java-1.8.0-openjdk-... java-11-openjdk.x86_64 : OpenJDK 11 Runtime Environment java-11-openjdk-devel.x86_64 : OpenJDK 11 Development Environment java-11-openjdk-... java-17-openjdk.x86_64 : OpenJDK 17 Runtime Environment java-17-openjdk-devel.x86_64 : OpenJDK 17 Development Environment java-17-openjdk-... ...
2. Install the OpenJDK 17 JRE (java-17-openjdk) package.
herong$ sudo dnf install java-17-openjdk ... Installed: java-17-openjdk-1:17.0.1.0.12-2.el8_5.x86_64 java-17-openjdk-headless-1:17.0.1.0.12-2.el8_5.x86_64
3. Install the OpenJDK 17 JDK (java-17-openjdk-devel) package.
herong$ sudo dnf install java-17-openjdk-devel ... Installed: java-17-openjdk-devel-1:17.0.1.0.12-2.el8_5.x86_64
4. Verify the installation. The output shows that new OpenJDK 17 version is installed correctly. But it didn't update the "java" command with the newer version.
herong$ /usr/lib/jvm/java-17-openjdk-17.0.1.0.12-2.el8_5.x86_64/bin/java -version openjdk version "17.0.1" 2021-10-19 LTS OpenJDK Runtime Environment 21.9 (build 17.0.1+12-LTS) OpenJDK 64-Bit Server VM 21.9 (build 17.0.1+12-LTS, mixed mode, sharing) herong$ java -version openjdk version "1.8.0_312" OpenJDK Runtime Environment (build 1.8.0_312-b07) OpenJDK 64-Bit Server VM (build 25.312-b07, mixed mode)
5. Update the "java" command using the "update-alternatives" tool. It allows you to select the newer version.
herong$ sudo update-alternatives --config java
There is 2 programs that provide 'java'.
-----------------------------------------------
*+ 1 java-1.8.0-openjdk.x86_64 (
/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.312.b07-2.el8_5.x86_64/jre/bin/java)
2 java-17-openjdk.x86_64 (
/usr/lib/jvm/java-17-openjdk-17.0.1.0.12-2.el8_5.x86_64/bin/java)
Enter to keep the current selection[+], or type selection number: 2
herong$ java -version
openjdk version "17.0.1" 2021-10-19 LTS
OpenJDK Runtime Environment 21.9 (build 17.0.1+12-LTS)
OpenJDK 64-Bit Server VM 21.9 (build 17.0.1+12-LTS, mixed mode, sharing)
6. Update the "javac" command using the "update-alternatives" tool.
herong$ sudo update-alternatives --config javac
There is 2 programs that provide 'javac'.
-----------------------------------------------
*+ 1 java-1.8.0-openjdk.x86_64 (
/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.312.b07-2.el8_5.x86_64/bin/javac)
2 java-17-openjdk.x86_64 (
/usr/lib/jvm/java-17-openjdk-17.0.1.0.12-2.el8_5.x86_64/bin/javac)
Enter to keep the current selection[+], or type selection number: 2
herong$ javac -version
javac 17.0.1
Okay, I have the OpenJDK 17 installed with the Development Environment package which provides the Java compiler and other Java tools.
Table of Contents
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Running MySQL Database Server on Linux Systems
Running Python Scripts on Linux Systems
Conda - Environment and Package Manager
Install and Manage OpenJDK on CentOS
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