Java 8 | BigInteger longValueExact() Method with Examples (original) (raw)

java.math.BigInteger.longValueExact() was introduced in Java 8. It is an inbuilt function which converts the value of BigInteger to a long and checks for lost information. If the value of BigInteger is greater than 9,223,372,036,854,775,807 or less than -9,223,372,036,854,775,808; the method will throw ArithmeticException as BigInteger doesn’t fit in long range.Syntax:

public long longValueExact()

Return Value: This method returns the long value of this BigInteger.Exception: The method throws ArithmeticException if the value of BigInteger is greater than 9,223,372,036,854,775,807 or less than -9,223,372,036,854,775,808; as this range doesn’t fit in long range.Example:

Input: 98169894145 Output: 98169894145 Explanation: 98169894145 is given as input which is BigInteger and long value of 98169894145 is 98169894145

Input: -65416518651 Output: -65416518651 Explanation: -65416518651 is given as input which is BigInteger and long value of -65416518651 is -65416518651

Input: 10000000000000000000 Output: ArithmeticException Explanation: When 10000000000000000000 is tried to convert to long, since 10000000000000000000 > 9,223,372,036,854,775,807 (greater than a long's range), therefore it throws an arithmetic exception.

Below programs illustrates longValueExact() method of BigInteger class:Program 1: To demonstrate longValueExact() method for positive number <9,223,372,036,854,775,807

Java `

// Java program to demonstrate longValueExact() // method of BigInteger Class

import java.math.*;

public class GFG {

public static void main(String[] args)
{
    // Creating a BigInteger object
    BigInteger big;
    big = new BigInteger("98169894145");

    // print value of BigInteger
    System.out.println("BigInteger value : "
                       + big);

    // convert big to the long value
    long b1 = big.longValueExact();

    // print long value
    System.out.println("long converted value : "
                       + b1);
}

}

`

Output:

BigInteger value : 98169894145 long converted value : 98169894145

Program 2: To demonstrate longValueExact() method for negative number >-9,223,372,036,854,775,808

Java `

// Java program to demonstrate longValueExact() // method of BigInteger Class

import java.math.*;

public class GFG {

public static void main(String[] args)
{

    // Creating a BigInteger object
    BigInteger big = new BigInteger("-65416518651");

    // print value of BigInteger
    System.out.println("BigInteger value : "
                       + big);

    // convert big to the long value
    long b1 = big.longValueExact();

    // print long value
    System.out.println("long converted value : "
                       + b1);
}

}

`

Output:

BigInteger value : -65416518651 long converted value : -65416518651

Program 3: To demonstrate longValueExact() method for negative number <-9,223,372,036,854,775,808. It will throw Arithmetic Exception

Java `

// Java program to demonstrate longValueExact() // method of BigInteger Class

import java.math.*;

public class GFG {

public static void main(String[] args)
{

    // Creating a BigInteger object
    BigInteger big = new BigInteger("-10000000000000000000");

    // print value of BigInteger
    System.out.println("BigInteger value : "
                       + big);

    try {
        // convert big to the long value
        long b1 = big.longValueExact();

        // print long value
        System.out.println("long converted value : "
                           + b1);
    }
    catch (Exception e) {
        System.out.println("Exception: " + e);
    }
}

}

`

Output:

BigInteger value : -10000000000000000000 Exception: java.lang.ArithmeticException: BigInteger out of long range

Program 4: To demonstrate longValueExact() method for positive number >9,223,372,036,854,775,807. It will throw Arithmetic Exception

Java `

// Java program to demonstrate longValueExact() // method of BigInteger Class

import java.math.*;

public class GFG {

public static void main(String[] args)
{

    // Creating a BigInteger object
    BigInteger big = new BigInteger("10000000000000000000");

    // print value of BigInteger
    System.out.println("BigInteger value : "
                       + big);

    try {
        // convert big to the long value
        long b1 = big.longValueExact();

        // print long value
        System.out.println("long converted value : "
                           + b1);
    }
    catch (Exception e) {
        System.out.println("Exception: " + e);
    }
}

}

`