RunCatching for safe execution in Kotlin - Mini Project: Build & Apply

RunCatching for safe execution

📖 Scenario: Imagine you are writing a small Kotlin program that divides numbers. Sometimes, the divisor might be zero, which causes an error. You want to handle this safely without crashing the program.

🎯 Goal: You will build a Kotlin program that uses runCatching to safely execute a division operation and handle any errors gracefully.

📋 What You'll Learn

Create a function that divides two integers

Use runCatching to safely execute the division

Store the result or the error message

Print the final output showing success or failure

💡 Why This Matters

🌍 Real World

Handling errors safely is important in apps that deal with user input or external data, like calculators or data processors.

💼 Career

Many Kotlin jobs require writing robust code that does not crash on bad input. Using <code>runCatching</code> is a common way to handle exceptions cleanly.

1

Create a division function

Write a function called divide that takes two Int parameters named numerator and denominator. The function should return the result of dividing numerator by denominator as an Int.

Kotlin

// Write the function divide with parameters numerator and denominator
// Your code here

Need a hint?

Use the / operator to divide the two integers inside the function.

2

Use runCatching to safely execute division

Create a variable called result that uses runCatching to call the divide function with 10 as numerator and 0 as denominator.

Kotlin

fun divide(numerator: Int, denominator: Int): Int {
    return numerator / denominator
}

// Use runCatching to call divide(10, 0) and store in result
// Your code here

Need a hint?

Use runCatching { divide(10, 0) } to catch any exceptions from dividing by zero.

3

Extract success or failure message

Create a variable called message that uses result.fold to return the success value as a string or the failure exception message.

Kotlin

fun divide(numerator: Int, denominator: Int): Int {
    return numerator / denominator
}

val result = runCatching { divide(10, 0) }

// Use result.fold to create message with success or failure text
// Your code here

Need a hint?

Use fold on result to handle both success and failure cases.

4

Print the final message

Write a println statement to display the message variable.

Kotlin

fun divide(numerator: Int, denominator: Int): Int {
    return numerator / denominator
}

val result = runCatching { divide(10, 0) }

val message = result.fold(
    onSuccess = { value -> "Success: $value" },
    onFailure = { error -> "Failure: ${error.message}" }
)

// Print the message
// Your code here

Need a hint?

Use println(message) to show the result or error message.