OptionalDouble help us to create an object which may or may not contain a Double value. The isPresent() method help us to get the answer that double value is present in OptionalDouble object or not. If a double value is present, returns true, otherwise false.
Syntax:
public boolean isPresent()
Parameters: This method accepts nothing.
Return value: This method returns true if a value is present, otherwise false
Below programs illustrate isPresent() method:
Program 1:
// Java program to demonstrate // OptionalDouble.isPresent() method import java.util.OptionalDouble;
public class GFG {
public static void main(String[] args)
{
// create a OptionalDouble
OptionalDouble opDouble
= OptionalDouble.of( 3148.1345 );
// get value using isPresent()
System.out.println( "OptionalDouble"
+ " has a value= "
+ opDouble.isPresent());
}
} |
Output:
OptionalDouble has a value= true
Program 2:
// Java program to demonstrate // OptionalDouble.isPresent() method import java.util.OptionalDouble;
public class GFG {
public static void main(String[] args)
{
// create a OptionalDouble
OptionalDouble opDouble
= OptionalDouble.empty();
// try to get that value is present or not
boolean response = opDouble.isPresent();
if (response)
System.out.println( "Value present" );
else
System.out.println( "Value absent" );
}
} |
Output:
Value absent
References: https://docs.oracle.com/javase/10/docs/api/java/util/OptionalDouble.html#isPresent()