gradle java9 Could not target platform: 'Java SE 9' using tool chain: 'JDK 8 (1.8)'

Question

I want to use java9 on my gradle project inside eclipse oxygen. When I run:

Run as> Gradle Test on  GreeterTest.java

with the followin

Answer 1

in Eclipse make sure you have proper settings on Gradle build configuration.

Answer 2

I faced the same error with different JDK version, so i used the following code which works fine.

compileJava {
    options.fork = true
    options.forkOptions.javaHome = file('/Library/Java/JavaVirtualMachines/jdk-11.0.5.jdk/Contents/Home')
    targetCompatibility = 11
    sourceCompatibility = 11
}

Answer 3

Additionally to the other ways you tried:

Gradle has a default JVM set in your %userprofile%/.gradle/gradle.properties. This is in the folder "C:\Users\j.gradle\gradle.properties" for me:

org.gradle.java.home=C:/Program Files/AdoptOpenJDK/jdk-11.0.7.10-hotspot

That's where you should also put your newer JVM to make sure gradle can compile newer projects.

Answer 4

I changed the java_home and upgraded Gradle. Now it is working.