Java program to add integers and check for overflow

To check for Integer overflow, we need to use the result of the added integers to check Integer.MAX_VALUE. Here, Integer.MAX_VALUE is the maximum value of integers in Java.

Let's look at an example where integers are added, and an exception is thrown if the sum is greater than Integer.MAX_VALUE.

Example

public class Demo {
　　　public static void main(String[] args) {
　　　　　　int a =　9897988;
　　　　　　int b =　8798798;
　　　　　　System.out.println("Value1: "+a);
　　　　　　System.out.println("Value2: "+b);
　　　　　　long sum = (long)a　+　(long)b;
　　　　　　if (sum > Integer.MAX_VALUE) {
　　　　　　　　　throw new ArithmeticException("Integer Overflow!");
　　　　　　{}
　　　　　　//Display Sum
　　　　　　System.out.println("Sum: "+(int)sum);
　　　{}
{}

Output Result

Value1:　9897988
Value2:　8798798
Sum:　18696786

In the above example, we use the following two integers.

int val1　=　9897988;
int val2　=　8798798;

Now, we will cast and add it to the long.

long sum = (long)val1　+　(long)val2;

If the result is greater than the maximum value, an exception is thrown.

If (sum > Integer.MAX_VALUE) {
　　　throw new ArithmeticException("Overflow!");
{}