Bug: Build Server for Gradle picking up wrong Java somehow?

[quinnj]

Environment:

• VS Code Version:
• Extension Version:
• JDK Type & Version:
• OS Type & Version:

Step to Reproduce:
I'm trying to run my springboot application, but immediately running into a java version issue.

The "invalid source release: 21" seems to suggest that a non-Java-21 version is being used by Build Server for Gradle? If I check the java version in the vs code terminal, it seems fine:

➜  tvlr-app git:(main) java --version
openjdk 21 2023-09-19
OpenJDK Runtime Environment (build 21+35-2513)
OpenJDK 64-Bit Server VM (build 21+35-2513, mixed mode, sharing)

as well as via gradle:

➜  tvlr git:(main) ./gradlew --version

------------------------------------------------------------
Gradle 8.3
------------------------------------------------------------

Build time:   2023-08-17 07:06:47 UTC
Revision:     8afbf24b469158b714b36e84c6f4d4976c86fcd5

Kotlin:       1.9.0
Groovy:       3.0.17
Ant:          Apache Ant(TM) version 1.10.13 compiled on January 4 2023
JVM:          21 (Oracle Corporation 21+35-2513)
OS:           Mac OS X 14.1.1 aarch64

And indeed, if install the Gradle vs code extension and run the same gradle tasks from that extension tab, it works fine:

But it's when I try to run the springboot application "run" from the springboot extension tab that it's giving the original output failure for the "Build Server for Gradle" terminal tab.
Expected Behavior:

Actual Behavior:

Related Issues:

[cypher256]

Try setting the Java 21 path to java.import.gradle.java.home in settings.json.
Also, Gradle 8.5 or higher is required.

[quinnj]

That was it; thanks so much!

[gianluca-sabena]

I have the same problem.

I don't think setting java.import.gradle.java.home is the best solution because this force me to switch a settings when I need to test different Java version. I would prefer having the java version detected from the environment correctly.

I use sdkman https://sdkman.io/ and it is common for me to switch among different JVM.

I use vscode with WSL2 remote and ubuntu.

[cypher256]

@gianluca-sabena

Precedence:

1. java.import.gradle.java.home
2. java.jdt.ls.java.home (No settings required)
3. java.home (Deprecated)
4. JAVA_HOME environment variable
5. PATH environment variable

Gradle Daemon must be restarted for the changes to take effect.

[gigaSproule]

I had the same issue. Setting java.import.gradle.java.home resolved it, but according to the precedence, it shouldn't have been necessary.

For me, java.import.gradle.java.home was not set, java.jdt.ls.java.home is not set, java.home is not set and the JAVA_HOME environment variable is set. So this means that it's not actually using the JAVA_HOME environment variable of the system.

What this means is that when I upgrade my JDK version, I will have to update this setting every time.

[cypher256]

@gigaSproule
If VSCode is not configured, the version must be specified in build.gradle.

def javaVersion = 17
java.sourceCompatibility = javaVersion
compileJava.options.release = javaVersion

Above is the project version and below is the Gradle Daemon version.
java.import.gradle.java.home

Specify Project Java Version
https://github.com/cypher256/java-extension-pack?tab=readme-ov-file#specify-project-java-version

[gigaSproule]

@cypher256 I also have that specified in the build.gradle

sourceCompatibility = JavaVersion.VERSION_21
targetCompatibility = JavaVersion.VERSION_21

I can also see that VSCode is picking it up. As is the original issue, I can run the gradle commands via terminal, I can run the gradle commands via the gradle tab, but it's just the build server that isn't working.

When I set it to 17, it works, but anything higher than that and it doesn't like it.

[mastronardo]

@gigaSproule Hi, I had the same problem and I solved in this way:
android/app/build.gradle:

android {
 ...

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

    compileOptions {
       sourceCompatibility JavaVersion.VERSION_21
        targetCompatibility JavaVersion.VERSION_21
    }

    kotlinOptions {
        jvmTarget = '21'
    }
}

Whether despite these changes you still have errors, I recommend changing the settings in Android Studio.
Let me know how it goes!

[gigaSproule]

@mastronardo this isn't for an Android project, but a standard Java app.

Edit: I tried it anyway, and it stopped the error, but still fails to run the tests with a NoClassDefFoundError. So it doesn't fix the actual issue and even if it did work, it's not something that I would expect to be a real solution.

[dmitry-radzevich]

Actually, I think this bug should be re-opened, as the proposed way (setting explicitly a user-global java.import.gradle.java.home) is only a workaround.

The advertised search order is clearly not followed, as I have similar setup to the one quoted above: only JAVA_HOME is set for me to point to Eclipse Temurin JDK 21 and all other tools, including Gradle plugin, Runtime detection in Java plugin, etc. are working fine and only the Gradle build server complains:"

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':modules:common:compileJava'.
> error: release version 21 not supported

[charlly-code]

Please where can I set this "java.import.gradle.java.home", I'm facing the issue currently