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);
}
}
} |
Output:
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);
}
}
} |
Output:
LinkedHashSet: [10, 20, 30] Is the element '25' present: false