The equals() method of java.util.HashSet class is used verify the equality of an Object with a HashSet and compare them. The list returns true only if both HashSet contains same elements, irrespective of order.
Syntax:
public boolean equals(Object o)
Parameters: This method takes the object o as a parameter to be compared for equality with this set.
Returns Value: This method returns true if the specified object is equal to this set.
Below are the examples to illustrate the equals() method.
Example 1:
// Java program to demonstrate equals() // method of HashSet import java.util.*;
public class GFG {
public static void main(String[] argv)
{
// Creating object of HashSet<String>
HashSet<String>
arrset1 = new HashSet<String>();
// Populating arrset1
arrset1.add( "A" );
arrset1.add( "B" );
arrset1.add( "C" );
arrset1.add( "D" );
arrset1.add( "E" );
// print arrset1
System.out.println( "First HashSet: "
+ arrset1);
// Creating another object of HashSet<String>
HashSet<String>
arrset2 = new HashSet<String>();
// Populating arrset2
arrset2.add( "A" );
arrset2.add( "B" );
arrset2.add( "C" );
arrset2.add( "D" );
arrset2.add( "E" );
// print arrset2
System.out.println( "Second HashSet: "
+ arrset2);
// comparing first HashSet to another
// using equals() method
boolean value
= arrset1.equals(arrset2);
// print the value
System.out.println( "Are both set equal: "
+ value);
}
} |
Output:
First HashSet: [A, B, C, D, E] Second HashSet: [A, B, C, D, E] Are both set equal: true
Example 2:
// Java program to demonstrate equals() // method of HashSet import java.util.*;
public class GFG1 {
public static void main(String[] argv)
{
// Creating object of HashSet
HashSet<Integer>
arrset1 = new HashSet<Integer>();
// Populating arrset1
arrset1.add( 10 );
arrset1.add( 20 );
arrset1.add( 30 );
arrset1.add( 40 );
arrset1.add( 50 );
// print arrset1
System.out.println( "First HashSet: "
+ arrset1);
// Creating another object of HashSet
HashSet<Integer>
arrset2 = new HashSet<Integer>();
// Populating arrset2
arrset2.add( 10 );
arrset2.add( 20 );
arrset2.add( 30 );
// print arrset2
System.out.println( "Second HashSet: "
+ arrset2);
// comparing first HashSet to another
// using equals() method
boolean value = arrset1.equals(arrset2);
// print the value
System.out.println( "Are both set equal: "
+ value);
}
} |
Output:
First HashSet: [50, 20, 40, 10, 30] Second HashSet: [20, 10, 30] Are both set equal: false