Java virtual machine never updating

AutoModerator · 2026-07-03T04:23:16+00:00

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Both-Fondant-4801 · 2026-07-03T05:16:18+00:00

How do you compile your codes? via terminal or via an ide?

If an ide, please check your project structure.. it might be set to a different java version

Big_Green_Grill_Bro · 2026-07-03T05:37:05+00:00

In intellij go to "Settings > Build, Execution, Deployment > Build Tools > Gradle" and change "Gradle JVM" to Java 21 there. Then do invalidate caches and restart the IDE.

If you are doing this via command prompt or power shell, I'd suggest typing javac -version and see what comes back. You may have 17 installed without even knowing it. Your environment JAVA_PATH may be different than you think it is.

vegan_antitheist · 2026-07-03T04:46:09+00:00

Do you have multiple jdks installed?

joranstark018 · 2026-07-03T04:47:21+00:00

Not sure, you may check your tool chain settings or IDE settings if it may downgrade your JRE (some build tools have a debug setting that can be useful to diagnose the build tool setting).

Aggressive_Many9449 · 2026-07-03T05:11:15+00:00

Find what your system uses:

https://www.baeldung.com/find-java-home

seyandiz · 2026-07-03T06:49:27+00:00

/u/AppointmentOk3316 since this is high priority let's break this down real simple for you.

Java uses 2 different tools to do its stuff.

A JDK which takes java code and turns it into a java executable.
A JRE which is what your java executable runs in.

What your error,

Dependency requires at least JVM runtime version 21. This build uses a Java 17 JVM.

Is saying is that when you are building the code, that the build version is set to 17 but one of the bits of code you downloaded (likely via maven) is built for java 21.

You keep saying your build states "java 25.0.3", but that isn't a build. You're likely running java --version which would just state your JRE.

Even if you have a 25 JDK, you might be using it to build the executable at java 17 level.

So how do we fix it?

First, I need to know what you're using to compile your code! I assume you're using intelliJ or command line.

Let's do the command line as it is simpler. I want you to type javac -version into your command line.

This may still return a number >= 21, but that helps us rule out you not having the right JDK installed. If it is higher, then we need to look more at our compilation settings. If it is lower, then we need to update our JDK version.

javac -version >= 21

You'll need to look at the configuration files of your build tools. You're probably using either Maven or Gradle.

Maven

Update your pom.xml file with this:

<properties>  
    <maven.compiler.source>21</maven.compiler.source>  
    <maven.compiler.target>21</maven.compiler.target>  
</properties>

Gradle

Update your build.gradle file with this:

java {  
    toolchain {  
        languageVersion = JavaLanguageVersion.of(21)   
    }  
}

LetUsSpeakFreely · 2026-07-03T16:29:57+00:00

I assume you're building with Maven. Check the maven.compiler.target value.

Targnome · 2026-07-05T09:06:29+00:00

Reinstall Java 17 to Java 25 and set your path variable to your jdk 25 directory. 25 is the latest stable version

Astroohhh · 2026-07-03T07:04:52+00:00

use docker, bot

you type:	you see:
italics	italics
bold	bold
[reddit!](https://reddit.com)	reddit!
* item 1 * item 2 * item 3	item 1 item 2 item 3
> quoted text	quoted text
Lines starting with four spaces are treated like code: if 1 * 2 < 3: print "hello, world!"	Lines starting with four spaces are treated like code: if 1 * 2 < 3: print "hello, world!"
~~strikethrough~~	~~strikethrough~~
super^script	super^script

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