Exceptions are events that occur during the execution of a program that disrupt the normal flow of instructions. Kotlin provides a powerful mechanism to deal with exceptions. In this article, we'll take a look at how to handle exceptions in Kotlin.
An exception is an event that occurs during the execution of a program that disrupts the normal flow of instructions. When an exception occurs, the program terminates abruptly.
There are two types of exceptions: checked and unchecked. Checked exceptions are those that occur at compile time, such as when a file is not found. Unchecked exceptions are those that occur at runtime, such as when a divide-by-zero error occurs.
Kotlin provides a powerful mechanism to deal with exceptions. The try/catch block is used to handle exceptions. The try block contains the code that may throw an exception. The catch block contains the code that handles the exception.
try {
// code that may throw an exception
} catch (e: Exception) {
// code that handles the exception
}
If an exception occurs in the try block, the catch block is executed. If no exception occurs, the catch block is skipped.
It is also possible to have multiple catch blocks to handle different types of exceptions.
try {
// code that may throw an exception
} catch (e: FileNotFoundException) {
// code that handles the FileNotFoundException
} catch (e: IOException) {
// code that handles the IOException
}
The finally block is optional. It is executed whether or not an exception occurs.
try {
// code that may throw an exception
} catch (e: Exception) {
// code that handles the exception
} finally {
// code that is always executed
}
Exceptions can be thrown explicitly using the throw keyword.
throw FileNotFoundException()
It is possible to create custom exceptions by extending the Exception class.
class MyException: Exception() {
}