Question

I have this code snippet

import java.util.ArrayList;
import java.util.List;

public class AssertTest {
    public static void main(String[] args) {
        List<String> list = new ArrayList<String>();
        assert(list.add("test")); //<-- adds an element

        System.out.println(list.size());
    }
}

Output:

0 

Why is the output list empty? How does assert behave here?
Thank you in advance!

Answer 1

You should enable assertion with -ea flag… such as;

java -ea -cp . AssertTest

Also using assertion is worst place for side effects..