In Java, LinkedHashSet class contains methods known as contains() which is used to return true if this set contains the specified element otherwise false.
Syntax:
public boolean contains(Object o)
Parameters: Element o as a parameter whose presence in this set is to be tested.
Return Type: A boolean value, true if this set contains the specified element.
Example 1:
Java
// Java program to Illustrate contains() Method // of LinkedHashSet class // For String value // Importing required classes import java.util.*; // Main class public class GFG { // Main driver method public static void main(String[] argv) throws Exception { // Try block to check for exceptions try { // Creating an empty LinkedHashSet // Declaring object of string type LinkedHashSet<String> linkset = new LinkedHashSet<String>(); // Populating above HashSet linkset.add( "A" ); linkset.add( "B" ); linkset.add( "C" ); // Printing all elements of above LinkedHashSet System.out.println( "LinkedHashSet: " + linkset); // Checking the existence of element // using contains() method boolean exist = linkset.contains( "C" ); // Printing boolean value if present or not System.out.println( "Is the element" + " 'C' present: " + exist); } // Catch block to check for exceptions catch (NullPointerException e) { // Display message if exception occurs System.out.println( "Exception thrown : " + e); } } } |
LinkedHashSet: [A, B, C] Is the element 'C' present: true
Example 2:
Java
// Java program to Illustrate contains() Method // of LinkedHashSet class // For Integer value // Importing required classes import java.util.*; // Main class public class GFG { // Main driver method public static void main(String[] argv) throws Exception { // Try block to check for exceptions try { // Creating an empty LinkedHashSet // Declaring object of integer type LinkedHashSet<Integer> linkset = new LinkedHashSet<Integer>(); // Populating above HashSet linkset.add( 10 ); linkset.add( 20 ); linkset.add( 30 ); // Printing all elements of above LinkedHashSet System.out.println( "LinkedHashSet: " + linkset); // Checking the existence of element // using contains() method boolean exist = linkset.contains( 25 ); // Printing boolean value if present or not System.out.println( "Is the element" + " '25' present: " + exist); } // Catch block to check for exceptions catch (NullPointerException e) { // Display message if exception occurs System.out.println( "Exception thrown : " + e); } } } |
LinkedHashSet: [10, 20, 30] Is the element '25' present: false