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

AtomicInteger runCount = 0L;
long runCount = myStream.stream()
    .filter(...)
    .peek(item -> { 
        foo();
        bar();
        runCount.incrementAndGet();
    });
System.out.println("The lambda ran " + runCount.incrementAndGet() + "times");