Kotlin Builder Pattern Demo

FoodOrder.kt

package org.mvnsearch.builder

class FoodOrder private constructor(builder: FoodOrder.Builder) {

    val bread: String?
    val meat: String?

    init {
        this.bread = builder.bread
        this.meat = builder.meat
    }

    class Builder {

        var bread: String? = null
            private set
        var meat: String? = null
            private set

        fun bread(bread: String) = apply { this.bread = bread }

        fun meat(meat: String) = apply { this.meat = meat }

        fun build() = FoodOrder(this)

    }
}

fun main(args: Array<String>) {
    val foodOrder = FoodOrder.Builder().bread("Italian").meat("Steak").build();
}