Could not target platform: 'Java SE 11' using tool chain: 'JDK 8 (1.8)'

Question

Trying to deploy my app to heroku, but it keeps failing with the error: Could not target platform: 'Java SE 11' using tool chain: 'JDK 8 (1.8)'

I have my JAVA_HOME,JAVA_PATH,and so on.. set up, i have an image of all of them here, i think they are correct. If i check java -version, and javac -version, they both show java 11.

I also tried putting to the root folder a system.properties.txt file and also instead of .txt a .gradle file with java.runtime.version=11 inside it.

Also i have this in my build.gradle:

sourceCompatibility = JavaVersion.VERSION_11
targetCompatibility = JavaVersion.VERSION_11

But it keeps installing jdk8 at the start of the deploy(git push heroku master) like this:

Gradle app detected
remote: -----> Spring Boot detected
remote: -----> Installing JDK 1.8... done
remote: -----> Building Gradle app...
remote: -----> executing ./gradlew build -x test
remote:        Downloading https://services.gradle.org/distributions/gradle-5.4.1-all.zip

here are the Images of the deploy failing and the environmental variables that are set up.

I have been with this problem for a week now, i think i tried all, but i would be really greatful if someone could help me with this. Thank you!

Answer 1

I had the same problem getting a "Java SE 11 using tool chain JDK 8" error. After Googling the problem, I was hinted toward the JAVA_HOME settings.

I use sdkman to manage my Java and Kotlin versions current version settings so after checking the current Java version configured in sdkman, I realized it was pointing to the GraalVM version 19 which targets Java 8.

So I simply reinstated the current JAVA_HOME to 11 with "sdkman use java 11.0.1-zulu" and everything was working fine.

Softjake