Computer scienceProgramming languagesKotlinObject-oriented programmingObject-oriented programming features

Delegate

Theory

A delegate from within

Report a typo

Figure out the relation between classes and interfaces and then complete the implementation of the ErrorHandler class, which relies on the implementation of the ILogHolder interface. Currently, it lacks a proper delegate and the function logErrorMessage(), which would use the Logger implementation as a delegate to print something when it's called from main().

Sample Input 1:

Sample Output 1: 

> Logger initialized.
> Access denied
> Out of memory
> I'm not an error
Write a program in Kotlin
/* Do not change the code below */

// ILogHolder is an interface that defines methods for printing and collecting logs,
// and a property for holding the current log
interface ILogHolder {
fun printLog()
fun collectLog(log: String)
var curLog: String
}

// Logger is a class that implements the ILogHolder interface
class Logger : ILogHolder {
// Print the current log
override fun printLog() {
println(curLog)
}

// Collect a log message and add it to the current log
override fun collectLog(log: String) {
curLog += "\n> $log"
}

// Initialize the current log
override var curLog: String = "> Logger initialized."
}
/* Do not change the code above */

// Introduce the delegate here, following the argument declaration
class ErrorHandler(base: ILogHolder) // Your code here
{
var errorMessage: String = "" // Current error message

// Get an error message and log it
fun getErrorMessage(msg: String) {
errorMessage = msg
logErrorMessage()
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