How to Call Parent Static Method Using Child Class In Kotlin?

In Kotlin, you can call a parent's static method using a child class by simply using the parent class name followed by the method name, separated by a dot. This allows you to access and execute the static method defined in the parent class within the child class without needing to create an instance of the parent class. This can be useful for reusing code and promoting code modularity in your application.

What is the syntax for calling a parent static method from a child class in Kotlin?

To call a parent static method from a child class in Kotlin, you can use the following syntax:

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ParentClassName.staticMethodName()

For example, if you have a parent class named Parent with a static method named staticMethod, and a child class named Child, you can call the staticMethod from the child class like this:

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Parent.staticMethod()

How can I access a static method from a child class in Kotlin?

To access a static method from a parent class in Kotlin, you can simply use the class name followed by the method name. Here's an example:

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open class Parent {
    companion object {
        fun staticMethod() {
            println("Static method from parent class")
        }
    }
}

class Child : Parent() {
    fun callStaticMethod() {
        Parent.staticMethod()
    }
}

fun main() {
    val child = Child()
    child.callStaticMethod()
}

In this example, the Parent class has a static method staticMethod() defined in its companion object. The Child class calls this static method by using Parent.staticMethod(). When you run the main() function, it will output "Static method from parent class" to the console.

What is the difference between static methods and companion objects in Kotlin?

In Kotlin, static methods are declared using the companion object keyword within a class.

Here are the differences between static methods and companion objects in Kotlin:

1. Accessibility: Static methods can be called directly on the class itself without needing an instance of the class, similar to static methods in other languages like Java. Companion objects are also accessed directly on the class, but they can contain properties and functions that are not directly accessible from outside the class, providing more control over their visibility.
2. Inheritance: Static methods cannot be overridden by subclasses, as they are not part of the inheritance hierarchy. Companion objects, on the other hand, can be extended by creating a new class that extends the original class and adds new members to the companion object.
3. Name Collisions: Since static methods are not associated with an instance of the class, name collisions can occur when multiple classes have static methods with the same name. Companion objects, on the other hand, are associated with the class they are defined in, so there is no risk of name collisions.
4. Extension Functions: Companion objects can also be used to define extension functions on a class, allowing you to add new functionality to existing classes without modifying their source code. Static methods cannot be used to define extension functions.

Overall, companion objects provide more flexibility and control over the visibility and inheritance of static methods in Kotlin.

How to use the super keyword to call a parent static method in Kotlin?

In Kotlin, you can use the super keyword to call a parent static method by simply referencing the parent class name followed by the :: operator and then the method name. Here's an example demonstrating how to call a parent static method using the super keyword:

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open class ParentClass {
    companion object {
        fun staticMethod() {
            println("Parent static method")
        }
    }
}

class ChildClass : ParentClass() {
    companion object {
        fun callParentStaticMethod() {
            super@ParentClass.staticMethod()
        }
    }
}

fun main() {
    ChildClass.callParentStaticMethod()
}

In this example, we have a parent class ParentClass with a static method staticMethod. The ChildClass extends ParentClass and defines a static method callParentStaticMethod which uses the super keyword to call the parent class's static method. When running the main function, it will output:

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Parent static method