OptionalDouble help us to create an object which may or may not contain a Double value. The equals(Object obj) method help us to compare this OptionalDouble object with the passed object as a parameter and it returns true if objects are equal.
The other object is considered equal to this OptionalDouble if:
- it is also an OptionalDouble and;
- both instances have no value present or;
- the present values are “equal to” each other via ==.
Syntax:
public boolean equals(Object obj)
Parameters: This method accepts an obj which is an object to be tested for equality.
Return value: This method returns true if the other object is “equal to” this object otherwise false.
Below programs illustrate equals(Object obj) method:
Program 1:
// Java program to demonstrate // OptionalDouble.equals(Object obj) method import java.util.OptionalDouble; public class GFG { public static void main(String[] args) { // Create first OptionalDouble object OptionalDouble opDouble1 = OptionalDouble.of( 452.13246 ); System.out.println( "OptionalDouble 1: " + opDouble1.toString()); // Create second OptionalDouble object OptionalDouble opDouble2 = OptionalDouble.of( 452.13246 ); System.out.println( "OptionalDouble 2: " + opDouble2.toString()); // Check if these two objects are equal // using equals(Object obj) System.out.println( "Are both objects equal: " + opDouble1.equals(opDouble2)); } } |
OptionalDouble 1: OptionalDouble[452.13246] OptionalDouble 2: OptionalDouble[452.13246] Are both objects equal: true
Program 2:
// Java program to demonstrate // OptionalDouble.equals(Object obj) method import java.util.OptionalDouble; public class GFG { public static void main(String[] args) { // Create first OptionalDouble object OptionalDouble opDouble1 = OptionalDouble.of( 3179464.92 ); System.out.println( "OptionalDouble 1: " + opDouble1.toString()); // Create second OptionalDouble object OptionalDouble opDouble2 = OptionalDouble.of( 4521.3246 ); System.out.println( "OptionalDouble 2: " + opDouble2.toString()); // Check if these two objects are equal // using equals(Object obj) System.out.println( "Are both objects equal: " + opDouble1.equals(opDouble2)); } } |
OptionalDouble 1: OptionalDouble[3179464.92] OptionalDouble 2: OptionalDouble[4521.3246] Are both objects equal: false
References: https://docs.oracle.com/javase/10/docs/api/java/util/OptionalDouble.html#equals?(Object obj)