Logs do not flush before Java exit

[ZachBien]

🐛 Bug Report

Affected Languages

• TypeScript or Javascript
• Python
• Java
• .NET (C#, F#, ...)
• Go

General Information

• JSII Version: 1.33.0 (build 7951e32), typescript 3.9.10
• Platform: Darwin Kernel Version 18.7.0

What is the problem?

console.log("Log lines") are not guaranteed to be written when executed in the Java export. It appears that the logs are not flushed in JavaScript before the Java program exits. Sleeping/Debugging at the end of the the Java program allows the JavaScript logs to be written.

Jsii TS code:

export class MockSleeper implements ISleeper {
    sleep(timeMillis: number): void {
        console.log(`Mocked implementation! Not performing real sleep of ${timeMillis}`);
    }
}

Java code:

public static void main(String[] args) {
    MockSleeper m = new MockSleeper();
    m.sleep(39);
    System.out.println("debug here");
}

I will only see the output from the TS log (Mocked impl...) if I debug the Java program at the last line.

[RomainMuller]

@all-contributors add @ZachBien for bug

[allcontributors]

@RomainMuller

I've put up a pull request to add @ZachBien! 🎉

[RomainMuller]

Okay I was able to reproduce this on JDK8 (Amazon Corretto 8), but not with Amazon Corretto 17.

It does look like this might be caused by how the JVM handles the subprocess...

[github-actions]

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