Compile with Java 11 to Java 8 language level

Help/Discuss
5

Or to show some concrete alternatives:

This will result in Java 8 compatible bytecode and will restrict the API to Java 8 too

java {
    toolchain {
        languageVersion.set(JavaLanguageVersion.of(11))
    }
}

tasks.compileJava {
    options.release.set(8)
}

This will set source and target compatibility to Java 8 but will still allow to use Java 11 API

java {
    toolchain {
        languageVersion.set(JavaLanguageVersion.of(11))
    }
}

tasks.compileJava {
    sourceCompatibility = "${JavaVersion.VERSION_1_8}"
}

This will use the Java 8 toolchain for exactly that task:

java {
    toolchain {
        languageVersion.set(JavaLanguageVersion.of(11))
    }
}

tasks.compileJava {
    javaCompiler.set(javaToolchains.compilerFor {
        languageVersion.set(JavaLanguageVersion.of(8))
    })
}

There are many different ways, depending on the actual needs. :slight_smile: