ArithmeticException in Java

In this article, we will learn what is ArithmeticException in Java, common causes, practical examples, solutions, and tips to avoid ArithmeticException.

What is ArithmeticException? 

ArithmeticException is a runtime exception in Java that gets thrown when an exceptional arithmetic condition has occurred. In most cases, it is due to an operation that doesn't adhere to mathematical rules and conventions. 

Primary Culprit: Division by Zero The most frequent scenario where this exception arises is when the code attempts to divide an integer by zero.

ArithmeticException Class Diagram

Note that from the above class diagram, ArithmeticException extends RuntimeException class.

Java ArithmeticException Example

In the below example, ArithmeticException occurs when an integer is divided by zero.
package com.javaguides.corejava;

public class ArithmeticExceptionExample {

    public static void main(String[] args) {
        try {
            int result = 30 / 0; // Trying to divide by zero
        } catch (ArithmeticException e) {
            System.err.println("ArithmeticException caught!");
ArithmeticException caught!
java.lang.ArithmeticException: / by zero
 at com.javaguides.corejava.ArithmeticExceptionExample.main(ArithmeticExceptionExample

Common Causes

Division by Zero: As seen in the example above, attempting to divide an integer by zero triggers this exception. 

Certain Mathematical Operations: Some specific mathematical computations, when they don't make sense or aren't defined, can lead to this exception. 

Unchecked or Unsafe Math Operations: Performing arithmetic without validating inputs. 

Solutions and Best Practices 

1. Always Validate Inputs

 If you're performing division or any arithmetic that depends on user inputs, always check and sanitize the inputs.
if(divisor != 0) {
    int result = number / divisor;
} else {
    System.out.println("Cannot divide by zero.");

2. Use try-catch Wisely 

While it's essential to prevent errors from happening in the first place, it's equally important to handle them gracefully when they do.

try {
    int result = number / divisor;
} catch (ArithmeticException e) {
    System.out.println("Arithmetic error: " + e.getMessage());

3. Consider Other Data Types 

For division operations, using data types like float, double, or BigDecimal can provide non-infinite results when dividing by zero, though they have their own sets of considerations.
double result = 10.0 / 0.0;
System.out.println(result); // Outputs: Infinity

Tips to Avoid ArithmeticException 

Educate Yourself: If you're working with complex mathematical operations, ensure you understand the mathematics behind them. Many mathematical operations have undefined results in certain conditions.

Logging: Implement proper logging mechanisms. If an ArithmeticException does occur, logs can help trace back to the precise operation causing it. 

Unit Testing: Implement unit tests, especially for the portions of your code responsible for calculations. This can help catch and address potential arithmetic issues before they reach production.