Lambdas

Making an implementation of interfaces that only require one method turns out to be a common task for a Java developer.

interface Band {
    void playHitSong();
}

class Starcadian implements Band {
    @Override
    public void playHitSong() {
        IO.println("ultralove");
    }
}

As such there is a mechanism called "lambdas" which lowers the effort required to do so.

interface Band {
    void playHitSong();
}

class Main {
    void main() {
        Band starcadian = () -> IO.println("ultralove");
        starcadian.playHitSong();
    }
}