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
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