Java Math subtractExact(int a , int b) method

The java.lang.Math.subtractExact() is a built-in math function in java that returns the difference of the arguments. It throws an exception if the result overflows an int. As subtractExact(int a, int b) is static, so object creation is not required.

Syntax:

public static int subtractExact(int a, int b)

Parameters:

• a: the first value
• b: the second value to be subtracted from the first

Return Type: This method returns the difference between the arguments.

Exception: It throws ArithmeticException – if the result overflows an int

Example: To show the working of java.lang.Math.subtractExact() method. 

java

// Java program to demonstrate working
// of java.lang.Math.subtractExact() method

import java.lang.Math;

class Gfg1 {

    // driver code
    public static void main(String args[])
    {
        int a = 300;
        int b = 200;

        System.out.println(Math.subtractExact(a, b));
    }
}

Output

100

Example:

java

// Java program to demonstrate working
// of java.lang.Math.subtractExact() method

import java.lang.Math;

class Gfg2 {

    // driver code
    public static void main(String args[])
    {
        int x = Integer.MIN_VALUE;
        int y = 10;

        System.out.println(Math.subtractExact(x, y));
    }
}

Output:

Runtime Error:
Exception in thread "main" java.lang.ArithmeticException: integer overflow
    at java.lang.Math.subtractExact(Math.java:829)
    at Gfg2.main(File.java:13)

Example:

Java

class A {

    // Main driver code
    public static void main(String[] args)
    {
        int a = 5; // integer value 5
        int b = 3; // integer value 3

        int result = Math.subtractExact(a, b);

        // Print statement
        System.out.println("The difference of " + a
                           + " and " + b + " is " + result);
    }
}

Output

The difference of 5 and 3 is 2