besidev/jdkmon

A little tool written in JavaFX that monitors your installed JDK's and inform you about updates

JDKMon

JDKMon Home

JDKMon is a little tool written in JavaFX that tries to detect all JDK's installed on your machine and will inform you about new updates and vulnerabilities of each OpenJDK distribution found. In addition JDKMon is also able to monitor JavaFX SDK versions that are installed on your machine.

(On MacOS you need at least version 11.0 to run JDKMon)

At the moment the following distributions will be identified:

• AdoptOpenJDK
• AdoptOpenJDK J9
• Bi Sheng
• Corretto
• Debian (pkgs not downloadable)
• Dragonwell
• Gluon GraalVM
• GraalVM CE8, CE11, CE16, CE17, CE19, CE20
• GraalVM Community
• GraalVM
• JetBrains
• Kona
• Liberica
• Liberica Native
• Mandrel
• Microsoft
• OJDK Build
• Open Logic
• Oracle (not all pkgs downloadable)
• Oracle OpenJDK
• RedHat (pkgs not downloadable)
• SAP Machine
• Semeru
• Semeru Certified
• Temurin
• Trava
• Zulu
• Zulu Prime

In case the distribution found was not identified it will be mentioned in the main window as "Unknown build of OpenJDK". If you stumble upon this case, please file an issue and mention the distribution incl. version that you are using.

JDKMon can be build for:

• Windows x64
• MacOS x64
• MacOS aarch64
• Linux x64
• Linux aarch64

You can always check if you have the latest version install by taking a look at the About window. This can be opened by selecting About from the menu. If there is a new version available you will find a link in the About window that will open the page with the latest release in your default browser.

You could also always get the latest version here.

Depending on the operating system it will try to find the JDK's in the following folders:

MacOS: /System/Volumes/Data/Library/Java/JavaVirtualMachines/

Windows: C:\Program Files\Java\

Linux: /usr/lib/jvm(FXTrayIcon only supports a few linux distros)

You can change the folders JDKMon is scanning for installed JDK's by selecting the "Add JDK search path" menu entry. The selected path will be added to the list of folders stored in the jdkmon.properties file in your user home folder. JDKMon will scan all given folders for installed JDK's.

If you would like to reset the folders that should be scanned to the default, simply select "Default JDK search path" in the menu.

You can also change the folders JDKMon is scanning for JavaFX SDK's by selecting the "Add JavaFX search path" menu entry. The selected path will be added to the list of folders stored in the jdkmon.properties file in your user home folder. You just need to add the folder than contains all your javafx-sdk-mm.ii.uu folders.

If you would like to reset the folders that should be scanned for JavaFX SDK's to the default, simply select "Default JavaFX search path". It will be reset to the your home folder.

You can search and download for a JDK from different distributions in the dialog that opens when you select "Download a JDK" from the menu.

The application will stay in the system tray with an icon. If you click the icon a menu will appear where you can select

JDK Main: The main window

Rescan: Will rescan for installed JDK's and check for updates

Add search path: Will open the directory chooser to add a path to the search paths

Default search path: Will reset the search path to the platform dependent default

Remember download folder: When remember download folder is active you don't have to select a download folder everytime

Download a JDK: Opens a dialog where you can search/download a JDK from different distributions

Exit: Exit the application `

ATTENTION:
When running the application via java -jar on Linux you might have to add -Djdk.gtk.version=2 to make it work correctly e.g. java -Djdk.gtk.version=3 -jar JDKMon-linux-22.0.0.jar

On Mac and Windows the dark mode will be detected automatically and the user interface will adjust it's design to either dark or light mode. On Linux you can change the variable "dark_mode" in the jdkmon.properties file (in your user folder) to "TRUE" to see the application in dark mode. The application will only check for dark/light mode during startup and won't change when it is running.

The main window will show you all JDK's found by JDKMon and if there is an update available it will show you the archive types of the available updates. In the image below you can see that there is an update for Zulu(FX) available and that you can download it as a tar.gz file. To download an update just click on the archive type tag and choose a folder where the download should be stored.

If an update is available and there are release details available, a little blue dot with a question mark will appear at the end of the packages list. When clicking on the dot the default browser will open with the release details over at foojay.io

JDKMon will not only help you to keep your installed OpenJDK distributions up to date but will also check the NVD (National Vulnerability Database) for known vulnerabilities (CVE - Common Vulnerability and Exposure) related to their version number. If you have for example installed an OpenJDK distribution with the version 11.0.13, JDKMon will check the NVD for known vulnerabilities of OpenJDK with the version number 11.0.13. In case JDKMon will find vulnerabilities, it will indicate this with a red square with an exclamation mark behind the version number. Meaning to say if you have for example Zulu 11.0.13 and Liberica 11.0.13 installed ony your machine, JDKMon will show you the vulnerabilties, it found for OpenJDK 11.0.13 for both distributions. So there is no guarantee that your installed distribution is really affected by the CVE's found in the NVD but you at least get the info that there are vulnerabilities for 11.0.13.

If you hover over a distribution, a tooltip will pop up that shows you the path where the distribution is installed, the number of modules the distribution comes with if it is modular and the size of the folder it is installed in.

When you click on the yellow circle a window will open which shows the CVE's found. You can click on each CVE to open it in a browser with more detailled information.

In the menu you will find an entry named "JEP's, JSR's, Projects". This will open a dialog with 3 drop down boxes as you can see in the following image.

When selecting one item of those boxes, it will open the related JEP, JSR or project in your default browser so that you can read more about it.

User Interface

How it looks on MacOS and Linux (light/dark mode):

How it looks on Windows (light/dark mode):

Additional properties

In your user home folder (e.g. /Users/YOUR_USERNAME or /home/YOUR_USERNAME) you will find a file named jdkmon.properties. This file contains the following settings:

searchpath=THE PATHS THAT WILL SCANNED FOR JDK'S (default depends on operating system)
remember_download_folder=TRUE/FALSE (default is FALSE)
download_folder=THE FOLDER WHERE DOWNLOADS WILL BE STORED (default is empty)
dark_mode=TRUE/FALSE (default is FALSE)
javafx_searchpath=PATH THAT WILL BE SCANNED FOR JAVAFX SDK'S (default is the user home folder)
features=loom,panama,metropolis,valhalla,lanai,kona_fiber (list of features to look for) EXPERIMENTAL!
autoextract=TRUE/FALSE Will directly extract downloaded JDK's (default is FALSE) EXPERIMENTAL!
show_unknown_builds=TRUE/FALSE Will show unknown builds of OpenJDK (default is FALSE) EXPERIMENTAL!

Switch JDK script

Since release 17.0.67 of JDKMon, it will create a script in your user home folder called

• switch-jdk.sh (Linux and Mac)
• switch-jdk.bat (Windows)

With this script you can switch to a specific JDK that was found by JDKMon. You can call the script with the -h parameter to get more help as follows:

>: ./switch-jdk.sh -h
. ./switch-jdk.sh JDK_NAME

JDK_NAME can be one of the following:
zulu_17_0_7_0
zulu_20_0_1_0
zulu_8_0_372_0
gluon_graalvm_22_1_0_1
zulu_21_0_0_0
graalvm_ce17_22_3_1_0
zulu_11_0_19_0

>: . ./switch-jdk.sh zulu_11_0_19_0
Switched to zulu 11.0.19
openjdk version "11.0.19" 2023-04-18 LTS
OpenJDK Runtime Environment Zulu11.64+19-CA (build 11.0.19+7-LTS)
OpenJDK 64-Bit Server VM Zulu11.64+19-CA (build 11.0.19+7-LTS, mixed mode)

>: java -version
openjdk version "11.0.19" 2023-04-18 LTS
OpenJDK Runtime Environment Zulu11.64+19-CA (build 11.0.19+7-LTS)
OpenJDK 64-Bit Server VM Zulu11.64+19-CA (build 11.0.19+7-LTS, mixed mode)

This script enables you to switch to a JDK of your choice for the current shell session.

Installation

Linux

Install the deb pkg via sudo dpkg -i jdkmon_22.0.0-1_amd64.deb

Windows

Make sure that you unblocked the msi package and set the rights correctly before you execute the msi installer

MacOS

Install the pkg and make sure it is not unblocked because it comes from an unknown source.

Installation problems

Linux

Make sure that you have the following programs installed before you execute build_appLinux.sh:

• binutils sudo apt install binutils
• fakeroot sudo apt install fakeroot
• rpm sudo apt install rpm

Problems opening CVE links

Linux

Make sure you have the xdg-open tool installed (it is part of the xdg-utils package).

• xdg-utils sudo apt install xdg-utils

No CVEs found

In case the cve files (in your home folder) are empty, delete the empty file and restart JDKMon. After the restart the file should be filled with data again.

• cvedb.json
• graalvm_cvedb.json