Android Development with Kotlin

The copy method

By default, the Kotlin compiler will also generate an appropriate copy method that will allow us to easily create a copy of an object:

    data class Product(var name: String, var price: Double) 
     
    val productA = Product("Spoon", 30.2) 
    print(productA) // prints: Product(name=Spoon, price=30.2) 
         
    val productB = productA.copy() 
    print(productB) // prints: Product(name=Spoon, price=30.2) 

Java does not have named argument syntax, so when calling the copy method in Java, we need to pass all arguments (the order of the arguments corresponds to the order of properties defined in the primary constructor). In Kotlin, this approach decreases the need for copy constructors or copy factories:

• The copy constructor takes a single argument whose ...