Multiple catch blocks in Kotlin - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of multiple catch blocks in Kotlin?

Multiple catch blocks allow you to handle different types of exceptions separately, so you can respond appropriately to each error type.

beginner

How do you write multiple catch blocks in Kotlin?

You write multiple catch blocks by placing several catch clauses after a try block, each catching a different exception type.

intermediate

What happens if an exception does not match any catch block?

If no catch block matches the exception type, the exception will propagate up the call stack and may crash the program if not handled elsewhere.

intermediate

Can you catch multiple exception types in a single catch block in Kotlin?

No, Kotlin does not support catching multiple exception types in a single catch block using the union operator (|). You need to use separate catch blocks for each exception type.

beginner

Example: What will this Kotlin code print?

try {
  val num = "abc".toInt()
} catch (e: NumberFormatException) {
  println("Number format error")
} catch (e: Exception) {
  println("General error")
}

It will print "Number format error" because the exception thrown is NumberFormatException, which matches the first catch block.

What is the correct way to handle different exceptions in Kotlin?

A Use multiple catch blocks after a try block

B Use one catch block with multiple exception types separated by commas

C Use if statements inside a single catch block

D Use a finally block only

Kotlin uses multiple catch blocks to handle different exceptions separately.

If an exception is not caught by any catch block, what happens?

A The program continues normally

B The exception is ignored

C The exception propagates up and may crash the program

D The finally block catches it automatically

Uncaught exceptions propagate up the call stack and can crash the program if not handled.

Which catch block will handle a NullPointerException if you have these catch blocks? 1) catch (e: IOException) 2) catch (e: Exception)

A Both

B catch (e: IOException)

C Neither

D catch (e: Exception)

NullPointerException is a subclass of Exception, so the second catch block will handle it.

Can you reorder catch blocks arbitrarily in Kotlin?

A No, more specific exceptions should come before general ones

B Yes, order does not matter

C No, general exceptions should come before specific ones

D Yes, but only if you use finally

More specific exceptions must come before general ones to avoid unreachable code.

What keyword starts a block where exceptions are caught in Kotlin?

A catch

B try

C throw

D finally

The try keyword starts the block where exceptions might be thrown and caught.

Explain how multiple catch blocks work in Kotlin and why their order matters.

Think about catching specific exceptions before general ones.

Describe what happens when an exception is thrown inside a try block and how Kotlin decides which catch block to run.

Focus on how Kotlin matches exception types to catch blocks.