The Java.util.HashSet.contains() method is used to check whether a specific element is present in the HashSet or not. So basically it is used to check if a Set contains any particular element.
Syntax:
Hash_Set.contains(Object element)
Parameters: The parameter element is of the type of HashSet. This is the element that needs to be tested if it is present in the set or not.
Return Value: The method returns true if the element is present in the set else return False.
Below program illustrate the Java.util.HashSet.contains() method:
// Java code to illustrate HashSet.contains() method import java.io.*; import java.util.HashSet; public class HashSetDemo { public static void main(String args[]) { // Creating an empty HashSet HashSet<String> set = new HashSet<String>(); // Using add() method to add elements into the Set set.add( "Welcome" ); set.add( "To" ); set.add( "Geeks" ); set.add( "4" ); set.add( "Geeks" ); // Displaying the HashSet System.out.println( "HashSet: " + set); // Check for "Geeks" in the set System.out.println( "Does the Set contains 'Geeks'? " + set.contains( "Geeks" )); // Check for "4" in the set System.out.println( "Does the Set contains '4'? " + set.contains( "4" )); // Check if the Set contains "No" System.out.println( "Does the Set contains 'No'? " + set.contains( "No" )); } } |
HashSet: [4, Geeks, Welcome, To] Does the Set contains 'Geeks'? true Does the Set contains '4'? true Does the Set contains 'No'? false
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