Java 8: preferred way to count iterations of a lambda?

Question

I face the same problem often. I need to count the runs of a lambda for use outside the lambda.

E.g.:

myStream.stream().filter(...).forEa         


        

Answer 1

As an alternative to sync hassling AtomicInteger one could use an integer array instead. As long as the reference to the array does not get another array assigned (and that's the point) it can be used as a final variable while the values of the fields can change arbitrarily.

    int[] iarr = {0}; // final not neccessary here if no other array is assigned
    stringList.forEach(item -> {
            iarr[0]++;
            // iarr = {1}; Error if iarr gets other array assigned
    });