CODESAMPLE

Master-Slave - Kotlin

Master-Slave Kotlin

The Master-Slave pattern involves one object (the Master) controlling and coordinating the actions of one or more other objects (the Slaves). The Master delegates tasks to the Slaves and may aggregate their results. This implementation uses Kotlin’s data classes for simplicity and a functional approach for task delegation. The Master holds a list of Slave objects and distributes work via a higher-order function executeTasks. This leverages Kotlin’s concise function syntax and immutability where appropriate, fitting the language’s modern, expressive style. The Slave interface defines a single execute method, promoting loose coupling.

// Slave interface
interface Slave {
    fun execute(task: String): String
}

// Concrete Slave implementation
data class WorkerSlave(private val id: Int) : Slave {
    override fun execute(task: String): String {
        return "Worker $id executing: $task"
    }
}

// Master class
class Master(private val slaves: List<Slave>) {
    fun executeTasks(tasks: List<String>): List<String> {
        return slaves.map { slave ->
            tasks.map { task -> slave.execute(task) }
        }.flatten()
    }
}

// Example Usage
fun main() {
    val slave1 = WorkerSlave(1)
    val slave2 = WorkerSlave(2)
    val master = Master(listOf(slave1, slave2))

    val tasks = listOf("Task A", "Task B", "Task C")
    val results = master.executeTasks(tasks)

    results.forEach(println)
}