AbstractCollection removeAll() method in Java with Example

// Java code to illustrate removeAll()
import java.util.*;

public class AbstractCollectionDemo {
    public static void main(String args[])
    {

        // Creating an empty AbstractCollection
        AbstractCollection<String> collection
            = new ArrayList<String>();

        // Use add() method to add
        // elements in the AbstractCollection
        collection.add("Geeks");
        collection.add("for");
        collection.add("Geeks");
        collection.add("10");
        collection.add("20");

        // Output the AbstractCollection
        System.out.println("AbstractCollection: "
                           + collection);

        // Creating an empty AbstractCollection
        AbstractCollection<String> colcollection
            = new ArrayList<String>();

        // Use add() method to add
        // elements in the AbstractCollection
        colcollection.add("Geeks");
        colcollection.add("for");
        colcollection.add("Geeks");

        // Remove the head using remove()
        boolean changed
            = collection.removeAll(colcollection);

        // Print the result
        if (changed)
            System.out.println("Collection removed");
        else
            System.out.println("Collection not removed");

        // Print the final AbstractCollection
        System.out.println("Final AbstractCollection: "
                           + collection);
    }
}

// Java code to illustrate removeAll()
import java.util.*;

public class AbstractCollectionDemo {
    public static void main(String args[])
    {

        // Creating an empty AbstractCollection
        AbstractCollection<Integer> collection
            = new ArrayList<Integer>();

        // Use add() method to
        // add elements in the AbstractCollection
        collection.add(1);
        collection.add(2);
        collection.add(3);
        collection.add(10);
        collection.add(20);

        // Output the AbstractCollection
        System.out.println("AbstractCollection: "
                           + collection);

        // Creating an empty AbstractCollection
        AbstractCollection<Integer> colcollection
            = new ArrayList<Integer>();

        // Use add() method to add elements
        // in the AbstractCollection
        colcollection.add(30);
        colcollection.add(40);
        colcollection.add(50);

        // Remove the head using remove()
        boolean changed
            = collection.removeAll(colcollection);

        // Print the result
        if (changed)
            System.out.println("Collection removed");
        else
            System.out.println("Collection not removed");

        // Print the final AbstractCollection
        System.out.println("Final AbstractCollection: "
                           + collection);
    }
}