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Getting the number of elements in the specified collection equal to the specified object.



package collection.demos;



import java.util.ArrayList;

import java.util.Collections;



public class GettingFrequencyOfElementInCollection{



    public static void main(String[] args) {

        ArrayList<String> list = new ArrayList<String>();

        list.add("A");

        list.add("B");

        list.add("C");

        list.add("A");

        list.add("D");

        list.add("A");

        list.add("B");

        System.out.println("Frequency of B in list : "+Collections.frequency(list, "B"));

    }

}

/*

OUTPUT : 

Frequency of B in list : 2

 */

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