How to resolve compileJava errors during heroku deployment?

Question

I worked as follows to deploy Intellij Spring Boot using gradle on heroku. I proceeded from the directory containing the source files.

> git init
> git add .
> git commit -m "first commit"
> heroku create
> git push heroku master

However, the following error occurred during the push process.

What went wrong: Execution failed for task ':compileJava'. invalid source release: 11

After the problem occurred, a file called system.properties was also created in the source file and the following input was also entered.

java.runtime.version=11

But it is still unresolved. How do I solve this problem?

user_10053052 · Answer

First you have to ensure your local development and your deployed instance are using the same version.

You specified a version with system.properties with content java.runtime.version=11 but haven't provided an image of the updated log. The log still says you are installing JDK 1.8.

Furthermore you should specify a Java version that is currently being supported. You can find the versions here: https://devcenter.heroku.com/articles/java-support#supported-java-versions

Java 7 - 1.7.0_302  
Java 8 - 1.8.0_292  
Java 11 - 11.0.11  
Java 13 - 13.0.7  
Java 15 - 15.0.3  
Java 16 - 16.0.1

user_17289798 · Answer

I've just face this problem following a course. Solve it by change the sourceCompatibility='17'(on my file) to '1.8' on my built.gradle file change sourceCompatibility='1.8' on build.gradle file and change the Gradle JMV on setting and JKD on project structure to 1.8. enter image description here

duno if the last change anything, but worked for me.

How to resolve compileJava errors during heroku deployment?

2 Answers