Java Long longValue() Method

The Long.longValue() method in Java is used to convert a Long object to a long primitive.

Table of Contents

1. Introduction
2. longValue() Method Syntax
3. Examples
   • Converting a Long to long
   • Performing Arithmetic Operations
   • Handling null Values
4. Real-World Use Case
5. Conclusion

Introduction

The Long.longValue() method is an instance method in the Long class in Java. It converts a Long object to a long primitive. This method is useful when you need to work with long primitives instead of Long objects, for example, in performance-critical applications or when interacting with APIs that require primitive types.

longValue()() Method Syntax

The syntax for the Long.longValue() method is as follows:

public long longValue()

The method returns:

• The long value represented by this Long object.

Examples

Converting a Long to long

The longValue() method can be used to convert a Long object to a long primitive.

Example

public class LongToLongExample {
    public static void main(String[] args) {
        Long longObject = 123456789L;
        long longValue = longObject.longValue();

        System.out.println("Long value of 123456789L: " + longValue);
    }
}

Output:

Long value of 123456789L: 123456789

In this example, the Long object 123456789L is converted to the long primitive 123456789.

Performing Arithmetic Operations

You can use the longValue() method to extract the long primitive from a Long object and perform arithmetic operations.

Example

public class ArithmeticOperationsExample {
    public static void main(String[] args) {
        Long longObject1 = 500L;
        Long longObject2 = 200L;

        long sum = longObject1.longValue() + longObject2.longValue();
        long difference = longObject1.longValue() - longObject2.longValue();
        long product = longObject1.longValue() * longObject2.longValue();
        long quotient = longObject1.longValue() / longObject2.longValue();

        System.out.println("Sum: " + sum);
        System.out.println("Difference: " + difference);
        System.out.println("Product: " + product);
        System.out.println("Quotient: " + quotient);
    }
}

Output:

Sum: 700
Difference: 300
Product: 100000
Quotient: 2

In this example, the Long objects 500L and 200L are converted to long primitives, and arithmetic operations are performed on them.

Handling null Values

When dealing with Long objects, it's important to handle null values to avoid NullPointerException.

Example

public class NullHandlingExample {
    public static void main(String[] args) {
        Long longObject = null;

        if (longObject != null) {
            long longValue = longObject.longValue();
            System.out.println("Long value: " + longValue);
        } else {
            System.out.println("The Long object is null.");
        }
    }
}

Output:

The Long object is null.

In this example, the code checks if the Long object is null before attempting to convert it to a long primitive.

Real-World Use Case

Converting User Input

In a real-world application, you might need to convert user input, which is often in the form of Long objects, to long primitives for calculations or storage.

Example

import java.util.Scanner;

public class UserInputExample {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("Enter a long number: ");

        Long longObject = scanner.nextLong();
        long longValue = longObject.longValue();

        long result = longValue * 2;
        System.out.println("The result of doubling the input is: " + result);

        scanner.close();
    }
}

Output (example input 123456789):

Enter a long number:
The result of doubling the input is: 246913578

In this example, the user input is read as a Long object and then converted to a long primitive for a calculation.

Conclusion

The Long.longValue() method in Java is a straightforward way to convert Long objects to long primitives. By understanding how to use this method, you can efficiently handle tasks that involve converting Long objects to long primitives in your Java applications. Whether you are performing arithmetic operations, handling user input, or avoiding null values, the longValue() method provides a reliable solution for these tasks.