The contains() method of Java AbstractSet is used to check whether an element is present in a set or not. It takes the element as a parameter and returns True if the element is present in the set.
Syntax:
public boolean contains(Object element)
Parameters: The parameter element is of type set. This parameter refers to the element whose occurrence is needed to be checked in the set.
Return Value: The method returns a boolean value. It returns True if the element is present in the set otherwise it returns False.
Below programs illustrate the AbstractSet.contains() method:
Program 1:
// Java code to illustrate// AbstractSet.contains() import java.util.*; public class GFG { public static void main(String args[]) { // Creating an empty set AbstractSet<String> abs = new TreeSet<String>(); // Use add() method to add // elements in the set abs.add("Geeks"); abs.add("for"); abs.add("Geeks"); abs.add("10"); abs.add("20"); // Displaying the set System.out.println("AbstractSet: " + abs); // Check if the set contains "Hello" System.out.println("\nDoes the set" + " contains 'Hello': " + abs.contains("Hello")); // Check if the set contains "20" System.out.println("Does the set" + " contains '20': " + abs.contains("20")); // Check if the set contains "Geeks" System.out.println("Does the set" + " contains 'Geeks': " + abs.contains("Geeks")); }} |
Output:
AbstractSet: [10, 20, Geeks, for] Does the set contains 'Hello': false Does the set contains '20': true Does the set contains 'Geeks': true
Program 2:
// Java code to illustrate// AbstractSet.contains() import java.util.*; public class GFG { public static void main(String args[]) { // Creating an empty set AbstractSet<Integer> abs = new TreeSet<Integer>(); // Use add() method to add // elements in the set abs.add(10); abs.add(20); abs.add(30); abs.add(40); abs.add(50); // Displaying the set System.out.println("AbstractSet:" + abs); // Check if the set contains 10 System.out.println("\nDoes the set " + "contains '10': " + abs.contains(10)); // Check if the set contains 50 System.out.println("\nDoes the set" + " contains '50': " + abs.contains(50)); // Check if the set contains 100 System.out.println("Does the set" + " contains '100': " + abs.contains(100)); }} |
Output:
AbstractSet:[10, 20, 30, 40, 50] Does the set contains '10': true Does the set contains '50': true Does the set contains '100': false
