Java comparison of two String Arrays

Question

I have a Question about comparing two String Arrays in an efficient way. I want to know which String of stArr1 contains any String of stArr2. If yes I want to print the String in which I found it and the index of the String in the stArr1.

What I got so far is an easy way of comparing two strings:

public class Main {

    public static void main(String[] args) {

        String[] stArr1 = {"I am testing", "hi", "bye bye"};
        String[] stArr2 = {"hello", "bye", "test"};

        int matches = 0;

        for (int i = 0; i < stArr1.length; i++) {
            for (int j = 0; j < stArr2.length; j++) {
                if (stArr1[i].contains(stArr2[j])) {
                    System.out.println(stArr1[i] + "found at index " i);
                }
            }
        }
    }
}

So the output should be: I am testing found at index 0, bye bye found at index 2.

Does anybody know a more efficient way? I tried a little bit with streams and am pretty sure there is a better solution than that.

I am sorry, I was in a rush and I didn't take my time to truly review this question, forget about what I have said, you code is right and efficient, whilst being easy to read and understand. — Stacklysm
– Stacklysm, Commented Jan 7, 2020 at 0:28
does "an efficient way" mean fastest execution time? least use of memory? fewest lines of code? — Kaan
– Kaan, Commented Jan 7, 2020 at 0:31
@user85421 The OP implied by example that they wanted to find multiple matches so all strings should be checked. — WJS
– WJS, Commented Jan 7, 2020 at 1:26
There is a solution that would be potentially more efficient, but it has nothing to do with the Stream API. You have to decide what your question is about, a Stream API solution or a more efficient approach. — Holger
– Holger, Commented Jan 7, 2020 at 8:42

Ravindra Ranwala · Accepted Answer · 2020-01-07 02:50:05Z

3

You can use IntStream combined with the anyMatch operator to get this thing done. Streams API is versatile such that any practical computation can be performed using streams. But, just because you can, doesn't mean you should. I still prefer the iterative approach and it is much more readable than the streams solution at least to me. So, my recommendation to you is to keep the iterative solution.

IntStream.range(0, stArr1.length)
    .filter(i -> Arrays.stream(stArr2).anyMatch(s -> stArr1[i].contains(s)))
    .forEach(i -> System.out.println(stArr1[i] + " found at index " + i));

edited Jan 7, 2020 at 2:50

answered Jan 7, 2020 at 2:38

Ravindra Ranwala

21.2k7 gold badges50 silver badges65 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Java comparison of two String Arrays

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related