Open In App

AbstractCollection addAll() Method in Java with Examples

Improve
Improve
Like Article
Like
Save
Share
Report

The addAll(Collection C) method of Java AbstractCollection is used to append all of the elements from a mentioned collection to this collection. The elements are added randomly without following any specific order. 

Syntax:

boolean addAll(Collection C)

Parameters: The parameter C is a collection of any type that is to be added to the collection. 

Return Value: The method returns true if it successfully appends the elements of the collection C to the existing collection otherwise it returns False. 

Below programs illustrate the AbstractCollection.addAll() method: 

Program 1: 

Java




// Java code to illustrate addAll()
// method of AbstractCollection
 
import java.util.*;
import java.util.AbstractCollection;
 
public class AbstractCollectionDemo {
    public static void main(String args[])
    {
 
        // Creating an empty collection
        AbstractCollection<String>
            abs1 = new TreeSet<String>();
 
        // Use add() method to add
        // elements into the Collection
        abs1.add("Welcome");
        abs1.add("To");
        abs1.add("Geeks");
        abs1.add("4");
        abs1.add("Geeks");
        abs1.add("TreeSet");
 
        // Displaying the Collection
        System.out.println("AbstractCollection 1: "
                           + abs1);
 
        // Creating another Collection
        AbstractCollection<String>
            abs2 = new TreeSet<String>();
 
        // Displaying the Collection
        System.out.println("AbstractCollection 2: "
                           + abs2);
 
        // Using addAll() method to Append
        abs2.addAll(abs1);
 
        // Displaying the Collection
        System.out.println("AbstractCollection 2: "
                           + abs2);
    }
}


Output:

AbstractCollection 1: [4, Geeks, To, TreeSet, Welcome]
AbstractCollection 2: []
AbstractCollection 2: [4, Geeks, To, TreeSet, Welcome]

Program 2: 

Java




// Java code to illustrate addAll()
// method of AbstractCollection
 
import java.util.*;
import java.util.AbstractCollection;
 
public class AbstractCollectionDemo {
    public static void main(String args[])
    {
 
        // Creating an empty collection
        AbstractCollection<Integer>
            abs1 = new TreeSet<Integer>();
 
        // Use add() method to add
        // elements into the Collection
        abs1.add(10);
        abs1.add(20);
        abs1.add(30);
        abs1.add(40);
        abs1.add(50);
 
        // Displaying the Collection
        System.out.println("AbstractCollection 1: "
                           + abs1);
 
        // Creating another Collection
        AbstractCollection<Integer>
            abs2 = new TreeSet<Integer>();
 
        // Displaying the Collection
        System.out.println("AbstractCollection 2: "
                           + abs2);
 
        // Using addAll() method to Append
        abs2.addAll(abs1);
 
        // Displaying the Collection
        System.out.println("AbstractCollection 2: "
                           + abs2);
    }
}


Output:

AbstractCollection 1: [10, 20, 30, 40, 50]
AbstractCollection 2: []
AbstractCollection 2: [10, 20, 30, 40, 50]


Last Updated : 26 May, 2023
Like Article
Save Article
Previous
Next
Share your thoughts in the comments
Similar Reads