Why error handling matters in Kotlin - See It in Action

Why error handling matters

📖 Scenario: Imagine you are making a simple calculator app that divides two numbers. Sometimes, users might enter zero as the divisor, which causes an error. We want to handle this error nicely so the app doesn't crash and shows a friendly message instead.

🎯 Goal: Build a Kotlin program that divides two numbers and uses error handling to catch division by zero errors, then shows a clear message.

📋 What You'll Learn

Create two variables for numbers to divide

Add a variable to hold the result

Use a try-catch block to handle division by zero

Print the result or an error message

💡 Why This Matters

🌍 Real World

Handling errors prevents apps from crashing and helps users understand what went wrong.

💼 Career

Error handling is a key skill for developers to write reliable and user-friendly software.

1

Create two number variables

Create two variables called numerator and denominator with values 10 and 0 respectively.

Kotlin

# Your code here

Need a hint?

Use val to create variables and assign the exact numbers.

2

Create a variable for the result

Create a variable called result of type Double? and set it to null.

Kotlin

val numerator = 10
val denominator = 0
# Your code here

Need a hint?

Use var because the result will change later. Use Double? to allow null.

3

Use try-catch to handle division

Write a try block that divides numerator by denominator and assigns it to result. Add a catch block to catch ArithmeticException and print "Cannot divide by zero!".

Kotlin

val numerator = 10
val denominator = 0
var result: Double? = null
# Your code here

Need a hint?

Use try and catch to handle errors. Perform division with doubles to avoid integer division issues, catching the exception if denominator is zero.

4

Print the result if no error

After the try-catch block, write an if statement that checks if result is not null. If so, print "Result: " followed by the result value.

Kotlin

val numerator = 10
val denominator = 0
var result: Double? = null
try {
    result = numerator.toDouble() / denominator.toDouble()
} catch (e: ArithmeticException) {
    println("Cannot divide by zero!")
}
# Your code here

Need a hint?

Check if result is not null before printing it.