Kotlin instanceof

Kotlin instanceof is a type checking operator that checks whether an object is of a specific type. It is similar to the Java instanceof operator.

The syntax for using Kotlin instanceof operator is as follows:

objectName is Type

Here, objectName is the object that we want to check the type of, and Type is the type we want to check for.

For example:

val obj: Any = "Hello Kotlin"
if (obj is String) {
    println("'$obj' is a String")
}

In this code snippet, the variable obj is of type Any, which is a supertype of all Kotlin classes. We are checking if obj is of type String using the instanceof operator. If obj is of type String, we print out a message saying so.

We can also use the instanceof operator in when expressions:

fun printType(obj: Any) {
    when (obj) {
        is Int -> println("$obj is an Int")
        is String -> println("$obj is a String")
        is Boolean -> println("$obj is a Boolean")
        else -> println("$obj is of an unknown type")
    }
}

In this example, we are using the instanceof operator to check what type of object we are dealing with and print out a message accordingly.

In conclusion, the Kotlin instanceof operator is a useful feature that allows us to check whether an object is of a specific type. It is similar to the Java instanceof operator and can be used in if statements and when expressions.