Nonlocal return from lambda?

Question

I am very new to programming so be gentle please! :D

public void test(Optional<String> testString){
    testString.ifPresent(s -> {
        //do stuff...
        System.out.println("Exit method");
        return;
    });
    //Log if it was not present
    Logger.log("...");
}

Here you have a code snippet. If the optional is present I do some stuff and want to exit the method by just calling return. I now wonder why my logger logs something although the testString is present. Can someone maybe point out what I'm missing please ? Thank you !

Answer 1

The problem is that when you do:

 testString.ifPresent(s -> {
        //do stuff...
        System.out.println("Exit method");
        return;
    });

You return from a lambda function, and not from the test(), as you expect.

Try using isPresent:

    if (testString.isPresent()) {
        System.out.println("Exit method");
        return;
    }
    //Log if it was not present
    System.out.println("Not present");