The containsAll() method of Java AbstractCollection is used to check whether two Collections contain the same elements or not. It takes one collection as a parameter and returns True if all of the elements of this collection is present in the other collection.
Syntax:
AbstractCollection.containsAll(Collection C)
Parameters: The parameter C is a Collection. This parameter refers to the collection whose elements occurrence is needed to be checked in this collection.
Return Value: The method returns True if this collection contains all the elements of other Collection otherwise it returns False.
Below programs illustrate the AbstractCollection.conatinsAll() method:
Program 1:
// Java code to illustrate boolean containsAll() import java.util.*; class AbstractCollectionDemo { public static void main(String args[]) { // Creating an empty Collection AbstractCollection<String> abs = new LinkedList<String>(); // Use add() method to // add elements in the collection abs.add("Geeks"); abs.add("for"); abs.add("Geeks"); abs.add("10"); abs.add("20"); // Creating another empty Collection AbstractCollection<String> abs2 = new LinkedList<String>(); // Use add() method to // add elements in the collection abs2.add("Geeks"); abs2.add("for"); abs2.add("Geeks"); abs2.add("10"); abs2.add("20"); // Check if the collection // contains same elements System.out.println("\nBoth the collections same: " + abs.containsAll(abs2)); }} |
Both the collections same: true
Program 2:
// Java code to illustrate boolean containsAll() import java.util.*; class AbstractCollectionDemo { public static void main(String args[]) { // Creating an empty Collection AbstractCollection<String> abs = new LinkedList<String>(); // Use add() method to // add elements in the collection abs.add("Geeks"); abs.add("for"); abs.add("Geeks"); // Creating another empty Collection AbstractCollection<String> abs2 = new LinkedList<String>(); // Use add() method to // add elements in the collection abs2.add("10"); abs2.add("20"); // Check if the collection // contains same elements System.out.println("\nBoth the collections same: " + abs.containsAll(abs2)); }} |
Both the collections same: false
Attention reader! Don’t stop learning now. Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready. To complete your preparation from learning a language to DS Algo and many more, please refer Complete Interview Preparation Course.
