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What JDK should I compile with to support most desktop users? [closed]

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I write a few small, free, desktop command-line applications in Java. I package those as JAR files in releases on GitHub. About a year ago in light of Oracle licensing changes, I switched from the Oracle JDK to Open JDK. Developing on Windows, this is what I currently have installed:
C:\Users\admin>java -version
openjdk version "17.0.1" 2021-10-19
OpenJDK Runtime Environment (build 17.0.1+12-39)
OpenJDK 64-Bit Server VM (build 17.0.1+12-39, mixed mode, sharing)
Now, about a week ago I was visiting a friend (also a software developer) and a reason came up where we wanted to run my application on his Windows box. He didn't have Java installed. So, watching over his shoulder, he went to the java.com "Download Java for Windows" page (currently listing Java Version 8 Update 341), downloaded, and installed it.
Then when he went to run my application, it failed to run, giving back an error along the lines of (paraphrasing from memory), "This version of the JRE does not support a later version of Java". This surprised both of us; he didn't know there was a later version of Java, and I didn't know compiling with the current OpenJDK would make a non-supported binary.
What's the best practice to fix this release problem?

Your user most likely ran into the issue that Java classes compiled with a newer class file version number do not run on older JVMs. If that is the only issue it can be addressed by recompiling ...
But there is a deeper issue. Older Java class libraries don't support all of the APIs provided by newer versions of Java. Also there have been some important architectural changes starting in Java 9 (e.g. addition of modules, removal of applets and closing off access to JDK internal classes) that "break" applications that run on older Java versions
What this means is that if you develop and test your code on Java 17 (say) there is a significant chance that it won't work on (say) Java 8 ... even if you compiled it for Java 8. And vice versa, because some APIs have been removed, or made inaccessible or ... work differently.
So my advice would be:
Decide on a specific range of Java versions you will support for your application; e.g. Java 8 LTS1 through Java 17 LTS.
Develop targeting the oldest Java version and its APIs.
Build and test on the Java oldest version.
Also test on (at least) all of the other LTS Java versions ... within the range you are supporting.
This will mean that you are limited to using the APIs and Java language features of your oldest supported version. This could hold you back, so you have to choose between that and supporting users with old (out of date) versions of Java.
The issue of users trying to install / use old versions of Java can be addressed in three ways:
Provide clear installation instructions to the user that say what kind / version(s) of Java they need to install, and where to get them from. (And how to set or configure JAVA_HOME if your application relies on that.)
Of course, some users won't read the instructions properly, but that is their lookout ...
Use jlink to turn your application into a custom JVM, and distribute your code that way.
Use jpackage to create platform specific binaries.
If you take the jlink or jpackage routes, the onus will be on you to push out new distributables whenever there are Java security patches that are relevant to your application. Your users won't be able to "just install the latest Java patches" anymore.
Note that jlink is available for Java 9 onwards, and jpackage from Java 16 onwards.
What JDK should I compile with to support most desktop users?
I don't think there is a good answer to that. We can't tell you what proportion of "desktop" users have each version of Java installed. (Or what they are permitted to install; e.g. by corporate policy.) But you can't support old Java versions indefinitely.
I did find this though:
Java 8 still dominates, but Java 17 wave is coming – survey - dated March 2022.
1 - Java 7 and earlier are all well beyond "end of life". You are not helping anyone by trying to support them.

Well, you have a few options...
First of all you can TARGET the version 8 runtime, but you can compile code from later revisions of the language. This may or may not work in all cases, as Java 9 and up do some things rather differently! Still, fairly vanilla Java that isn't doing weird ClassLoader stuff is LIKELY to work, and you can certainly avoid problematic constructs.
Secondly, you can simply stick to Java 8! It is ANCIENT but it is a virtually immortal LTS, due to the reason above that things in Java 9 are different. However, you will miss out on new things.
You COULD go whole hog and move on from Java 17 to GraalVM, which can be had in versions compatible with Java11, Java17, etc. It has the ability to compile code down to a completely stand-alone binary, using native-image, and again unless you do some fairly esoteric stuff, your code will work. The end result will be similar to using something like C++. You can even build shareable libraries.
I guess your other option is to just make sure people are not using Java8. Ideally they're using Java11, but I guess now java17 is the newest LTS, though few people seem to install it.

It looks like you are using Java 17. Developers of apps targeting Java version after 8 are expected to supply the runtime for running the application. This means there is no more 'downloading and installing Java' separately on the user side. This is also why the download page you refer to only offers Java 8.
In practice, this means that you should use jlink to create a runtime image (i.e. the thing that you would previously download and install) that can run your application.
jpackage can also be used to create application images and installers (it calls jlink under the hood). Both of those are tools that come with the JDK.
For your purposes I recommend using jpackage with something like this:
jpackage `
--win-console `
--main-jar app.jar `
--main-class Main `
--name myapp `
--type app-image `
--input input
In this command, input is a folder that has the main app.jar in it (Note: the input folder should not be the current directory, since that will lead to infinite recursion).
--win-console is also needed for console applications on Windows, since otherwise no console is created when running the app.
This command will create a myapp folder that you can zip/tar up and distribute.
This myapp folder has a myapp.exe launcher that can be used to run the application.
Also, note that this will create a runtime image with a default set of modules. If your jar is modular (i.e. it has a module-info file), I suggest using --module instead of --main-jar/--main-class, since that will use the module descriptor to determine the set of modules in the runtime image. (See jpackage --help)
Note that on Windows you will also need to install the wix toolkit. It can be installed easily through e.g. scoop:
scoop install wixtoolset

JDK and JRE version confusion

I've been working with Java for a bit now and the JDK/JRE version has given me quite a bit of trouble lately. I am developing using the Intellij IDEA IDE and it of course uses the latest version of the JDK, 14. However when I attempt to execute software compiled with JDK 14 outside the IDE, I get an error that the JRE isn't new enough to run this software. So I updated Java on my computer and another machine and attempt to run again without any success. After some digging, I tweaked my machine to use the JRE included in the JDK 14 which is compatible.
However it is kind of odd that I had to do that, one would think that the latest version of java should of been enough to run applications made with the latest version of the JDK (14). Right now Java is version 8 build 251 and says there is no newer update available. If JDK 14 is out for a while now, why would they not update the version of Java they ship?
The problem is partially solved, as only the machine I am using for development is capable of executing the created applications. Other people I've sent them to have been unable to run them, despite having the latest version of java. Also it is a pain to get the latest JDK, especially when having limited experience on how to get rid of old versions, change path point to the latest version, get the right package (open/oracle JDK) and do that for windows and several distrubutions of linux. What is going on? Did I get Java from the wrong place and everyone else as well? Why are oracle doing this and why are there no java updates since clearly there exists a newer version?

Starting with Java-11, separate JRE does not exist anymore. In other words, if you are using Java-11 or above, you should care about JDK only.
You should uninstall JRE-8 from your machine and make sure your JDK-14 bin folder in the PATH variable. Some application even requires JAVA_HOME to work and therefore you should make sure that your system has an environment variable called JAVA_HOME and its value set to the root folder of JDK-14 (i.e. one level above your JDK bin).
Q: What should my clients do to run my application compiled on JDK-14?
Ans: Your clients must install JDK-14. Also, check this thread for some alternatives.

You're confusing how IntelliJ or JDK are used on the OS. IntelliJ, now, often comes with its JDK binaries (but even this can be configured, IntelliJ can be configured to use any JDK/JRE build you'll provide to it); however, if you run your Java application out of IntelliJ, most likely you're using Java installed locally on your OS, which might be referenced via your JAVA_HOME environment variable.
I'd suggest to:
Check java -version in your shell (and hence you'll see what JVM instance your OS spins up when you run a Java application);
Check where java (on Windows, or which - on Linux) in your shell, to see all the Java binaries available on your OS.

Try to uninstall Java SE Development Kit and Java JRE(if you have both in your machine) and reinstall both again, JDK and JRE both, I am sharing my google drive link where you can find the latest version of both JDK and JRE and when you are done installing, add there bin folder path in the Environment Variables of your machine.

Java 11 does not set Java Environment Variable

usually when installing an updated JRE, the environment variables will be set so that running any java command in CMD will use the new version.
I've just installed JDK 11 which doesn't have a JRE equivalent - well it's in the JDK - but java commands are still being sent to JRE 8.
This is no problem for me, I can always change the environment vars myself and point to "C:\Program Files/java/jdk-11/bin/java.exe", but anyone who wants to use my program, which requires Java 11, will not have their variables set and it's a bit much to ask them to do so.
Why are they not being set on a standard Java 11 install? Am I being stupid?

Oracle is still pushing 8 as the "end user" Java install. That's why it's the only one you can find on java.com. Newer versions of Java are designed either for back-end use on servers, or to be bundled with the application itself. The latter option is what you want.

Upgrade Java version for Web Application

I have a web Application and i need to upgrade java jre version from 6 to 7 .I am using Eclipse as IDE.I tried to update the Jre from eclipse .I have even updated the JAVA_HOME environment variable but i am getting following error
C:\Program Files\Java\jdk1.7.0_55\jre..\lib\tools.jar
Please ensure you are using JDK 1.4 or above and
not a JRE (the com.sun.tools.javac.Main class is required).
In most cases you can change the location of your Java
installation by setting the JAVA_HOME environment variable.
Thanks

Download java hereand install it as a common application.
Then in Eclipse use Window->Prefrences->Java->Installed JREs

#Roman Bondar I guesss OP wanted to know more than just the setting.
Basically, JREs are meant to be downwards compatible, so that you are able to execute java classes compiled with version 6 with a runtime from java 7.
But as always, there may be special cases when things have to be changed, e.g. container or libraries. I remember a case back when I migrated to java 6 that it required a special version of JBoss.
Check out this Oracle blog as a starting point.

Multiple Java versions running concurrently under Windows

We have a couple of applications running on Java 5 and would like now to bring in an application based on Java 6. Can both java versions live together under Windows?
Is there any control panel to set the appropriate Java version for different applications, or any other way to set up, what version of Java will be used to run that particular application?

Of course you can use multiple versions of Java under Windows. And different applications can use different Java versions. How is your application started? Usually you will have a batch file where there is something like
java ...
This will search the Java executable using the PATH variable. So if Java 5 is first on the PATH, you will have problems running a Java 6 application. You should then modify the batch file to use a certain Java version e.g. by defining a environment variable JAVA6HOME with the value C:\java\java6 (if Java 6 is installed in this directory) and change the batch file calling
%JAVA6HOME%\bin\java ...

I was appalled at the clumsiness of the CLASSPATH, JAVA_HOME, and PATH ideas, in Windows, to keep track of Java files. I got here, because of multiple JREs, and how to content with it. Without regurgitating information, from a guy much more clever than me, I would rather point to to his article on this issue, which for me, resolves it perfectly.
Article by: Ted Neward: Multiple Java Homes: Giving Java Apps Their Own JRE
With the exponential growth of Java as a server-side development language has come an equivablent
exponential growth in Java development tools, environments, frameworks, and extensions.
Unfortunately, not all of these tools play nicely together under the same Java VM installation. Some
require a Servlet 2.1-compliant environment, some require 2.2. Some only run under JDK 1.2 or above,
some under JDK 1.1 (and no higher). Some require the "com.sun.swing" packages from pre-Swing 1.0
days, others require the "javax.swing" package names.
Worse yet, this problem can be found even within the corporate enterprise, as systems developed using
Java from just six months ago may suddenly "not work" due to the installation of some Java Extension
required by a new (seemingly unrelated) application release. This can complicate deployment of Java
applications across the corporation, and lead customers to wonder precisely why, five years after the
start of the infamous "Installing-this-app-breaks-my-system" woes began with Microsoft's DLL schemes,
we still haven't progressed much beyond that. (In fact, the new .NET initiative actually seeks to solve the
infamous "DLL-Hell" problem just described.)
This paper describes how to configure a Java installation such that a given application receives its own,
private, JRE, allowing multiple Java environments to coexist without driving customers (or system
administrators) insane...

It is absolutely possible to install side-by-side several JRE/JDK versions. Moreover, you don't have to do anything special for that to happen, as Sun is creating a different folder for each (under Program Files).
There is no control panel to check which JRE works for each application. Basically, the JRE that will work would be the first in your PATH environment variable. You can change that, or the JAVA_HOME variable, or create specific cmd/bat files to launch the applications you desire, each with a different JRE in path.

We can install multiple versions of Java Development kits on the same machine using SDKMan.
Some points about SDKMan are as following:
SDKMan is free to use and it is developed by the open source community.
SDKMan is written in bash and it only requires curl and zip/unzip programs to be present on your system.
SDKMan can install around 29 Software Development Kits for the JVM such as Java, Groovy, Scala, Kotlin and Ceylon. Ant, Gradle, Grails, Maven, SBT, Spark, Spring Boot, Vert.x.
We do not need to worry about setting the _HOME and PATH environment variables because SDKMan handles it automatically.
SDKMan can run on any UNIX based platforms such as Mac OSX, Linux, Cygwin, Solaris and FreeBSD and we can install it using following commands:
$ curl -s "https://get.sdkman.io" | bash
$ source "$HOME/.sdkman/bin/sdkman-init.sh"
Because SDKMan is written in bash and only requires curl and zip/unzip to be present on your system. You can install SDKMan on windows as well either by first installing Cygwin or Git Bash for Windows environment and then running above commands.
Command sdk list java will give us a list of java versions which we can install using SDKMan.
Installing Java 8
$ sdk install java 8.0.201-oracle
Installing Java 9
$ sdk install java 9.0.4-open
Installing Java 11
$ sdk install java 11.0.2-open
Uninstalling a Java version
In case you want to uninstall any JDK version e.g., 11.0.2-open you can do that as follows:
$ sdk uninstall java 11.0.2-open
Switching current Java version
If you want to activate one version of JDK for all terminals and applications, you can use the command
sdk default java <your-java_version>
Above commands will also update the PATH and JAVA_HOME variables automatically. You can read more on my article How to Install Multiple Versions of Java on the Same Machine.

It should be possible changing setting the JAVA_HOME environment variable differently for specific applications.
When starting from the command line or from a batch script you can use set JAVA_HOME=C:\...\j2dskXXX to change the JAVA_HOME environment.
It is possible that you also need to change the PATH environment variable to use the correct java binary. To do this you can use set PATH=%JAVA_HOME%\bin;%PATH%.

I use a simple script when starting JMeter with my own java version
setlocal
set JAVA_HOME="c:\java8"
set PATH=%JAVA_HOME%\bin;%PATH%;
java -version
To have a java "portable"
you can use this method here:
https://www.whitebyte.info/programming/java/how-to-install-a-portable-jdk-in-windows-without-admin-rights

Or use links. While it is rather unpleasant to update the PATH in a running environment, it's easy to recreate a link to a new version of JRE/JDK. So:
install different versions of JDK you want to use
create a link to that folder either by junction or by built-in mklink command
set the PATH to the link
If other version of java is to be used, delete the link, create a new one, PATH/JAVA_HOME/hardcoded scripts remain untouched

Invoking Java with "java -version:1.5", etc. should run with the correct version of Java. (Obviously replace 1.5 with the version you want.)
If Java is properly installed on Windows there are paths to the vm for each version stored in the registry which it uses so you don't need to mess about with environment versions on Windows.

If you use Java Web Start (you can start applications from any URL, even the local file system) it will take care of finding the right version for your application.

Using Java Web Start, you can install multiple JRE, then call what you need.
On win, you can make a .bat file:
1- online version:
<your_JRE_version\bin\javaws.exe> -localfile -J-Djnlp.application.href=<the url of .jnlp file.jnlp> -localfile -J "<path_temp_jnlp_file_.jnlp>"
2- launch from cache:
<your_JRE_version\bin\javaws.exe> -localfile -J "<path_of_your_local_jnlp_file.jnlp>"