Why does 'return' in this case exit the loop?

Under discussion

This is an example from Java in Two Semesters 6.8.3

static boolean containes(int[] arrayIn, int valueIn)
{
for (int currentElement : arrayIn)
{
if (currentElement == valueIn)
{
return true; // exit loop early if value found
}
}
return false; // value not present
}

It says that the RETURN TRUE will exit the loop early, meaning it won't return false as in the later line. I really can't seem to get my head around how it exists the loop rather than return BOTH true and FALSE, i.e., as i'ts not a 'for... else' loop, wouldn't the code just go through the next command below? Thanks for your help!

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Gellert Varga

Level 23 , Szekesfehervar, Hungary

23 February 2021, 23:40

With this loop: for (int currentElement : arrayIn) generally you can go through all the elements of the "arrayIn" array. But here you use the "return" command inside the loop, and this works like the "break" command: if your comparison-test finds a match, then it will break the loop immediately and sends back (returns) the result.

Gellert Varga

Level 23 , Szekesfehervar, Hungary

23 February 2021, 13:44

I think the code you wrote works well. Run the program. On line 7, change the number sent to the method. Try it with 1 and try it with other numbers. Always watch the output!

public class MyClass {

    public static void main(String args[]) {

        int[] array = new int[] {2,3,4,5,6,7,8,9} ;

        System.out.println(containes(array, 8));

    }

    static boolean containes(int[] arrayIn, int valueIn) {

        for (int currentElement : arrayIn) {
            if (currentElement == valueIn) {
                return true;
            }
        }

        return false;
    }
}