Your project is using Java 17 but the base image is for Java 11

[nyxz]

Environment:

• Jib version: 3.2.1
• Build tool: Gradle 7.3.1
• OS: Linux Fedora 33

Description of the issue:
When I run ./gradlew -Pprod bootJar jib I get the following error:
Your project is using Java 17 but the base image is for Java 11, perhaps you should configure a Java 17-compatible base image using the 'jib.from.image' parameter, or set targetCompatibility = 11 or below in your build configuration

Expected behavior:
The image should build with Java 17.

Steps to reproduce:

1. Create a Spring project with Java 17 and Gradle
2. Configure just the jib.to.image (without custom jib.from.image).
3. Run ./gradlew bootJar jib

jib-gradle-plugin Configuration:

jib {
    to {
        image = '<accountId>.dkr.<region>.amazonaws.com/<name>'
        credHelper = 'ecr-login'
    }
}

Log output:

...
> Task :compileJava
Note: Hibernate JPA 2 Static-Metamodel Generator 5.6.4.Final

> Task :jib FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':jib'.
> Your project is using Java 17 but the base image is for Java 11, perhaps you should configure a Java 17-compatible base image using the 'jib.from.image' parameter, or set targetCompatibility = 11 or below in your build configuration

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.

* Get more help at https://help.gradle.org

Deprecated Gradle features were used in this build, making it incompatible with Gradle 8.0.

You can use '--warning-mode all' to show the individual deprecation warnings and determine if they come from your own scripts or plugins.

See https://docs.gradle.org/7.3.1/userguide/command_line_interface.html#sec:command_line_warnings

Additional Information:
I'm using the default JHipster setup and trying to push to AWS ECR. Based on the #3483 I assume I shouldn't make any more configurations. I guess I can workaround by providing custom jib.from.image.

[chanseokoh]

According to this article, it sounds like JHipster currently uses Java 11 and you need to do some work to upgrade to Java 17.

For Jib, at least I see that they explicitly configure a Java 11 base image in gradle/docker.gradle. Try updating the config.

    from {
        image = "eclipse-temurin:11-jre-focal"
    }

[nyxz]

Yep, in order to use Java 17 and not 11 I just changed the target Java version to 17 and it started the app. I totally missed the docker.gradle config. Thank you and apologies for wasting your time. This solves my issue.

[declanTreanor]

@nyxz I'm stuck on a similar problem. Can you please spell out, as though I were six, what needs to be changed?