containsAll for nCopies of object in List

booobi :

I would like to check if an Arraylist contains n copies of the same element. Here's the problem:

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

public class testMain {
    public static void main(String[] args) {
        myClass myObject = new myClass("haha1");

        ArrayList a = new ArrayList();
        a.add(myObject);
        a.add(new myClass("haha2"));
        a.add(new myClass("haha3"));

        List b;
        b = Collections.nCopies(5, myObject);
        System.out.println(a.containsAll(b)); //prints true
    }

    static private class myClass {
        String a;

        myClass(String a) {
            this.a = a;
        }
    }
}

Problem 1: List b has a greater size than list a - should be false
Problem 2: List b has more than one myObject objects (as opposed to Lista - should be false

This doesn't work due to the way containsAll works, since I want to see if the object myObject is contained (in this case) 3 times in List a.

I know I can write my own method that would do exactly what I want, but I was wondering if there is an out of the box solution for this case or what would be the most "elegant" way of handling it.

EDIT: Removed clarification for my use of myClass as it was conflicting with given example.

Eran :

Use Collections.frequency(a,myObject) == 5 (or Collections.frequency(a,myObject) >= 5 if you don't mind if your Collection has more than 5 instances pf myObject).

int java.util.Collections.frequency(Collection c, Object o)

Returns the number of elements in the specified collection equal to the specified object. More formally, returns the number of elements e in the collection such that (o == null ? e == null : o.equals(e)).