How can you implement multiple constructors in a single class in Kotlin?

In Kotlin, a class can have one primary constructor and one or more secondary constructors.

1. Primary constructor: Defined in the class header. It can have parameters.

   class MyClass(private val someProperty: String) { // Primary constructor with a parameter
       // Class body
   }
   

2. Secondary constructors: Declared with the keyword constructor. If the class has a primary constructor, each secondary constructor must delegate to it directly or indirectly using the this() keyword.

   class AnotherClass(private val primaryValue: Int) { // Primary constructor
   
       constructor(anotherValue: String) : this(anotherValue.length) { // Secondary constructor delegating to primary
           // Secondary constructor logic
           println("Created with string: $anotherValue")
       }
   
       constructor(value1: Int, value2: Int) : this(value1 + value2) { // Another secondary constructor
           // Logic
           println("Created with two ints: $value1, $value2")
       }
   }
   

If there is no primary constructor, secondary constructors are not required to delegate to other constructors of the same class (but they can).

class ClassWithoutPrimary {

    constructor(value: Int) {
        println("Created with int: $value")
    }

    constructor(value: String) {
        println("Created with string: $value")
    }
}