How Does `super()` Enable Proper Constructor Invocation and Parent Method Access in Java Inheritance?

Exploring 'super()': Its Role in Java Inheritance

Java's 'super()' keyword plays a crucial role in object-oriented programming, particularly when dealing with inheritance. Let's dive into understanding its usage and capabilities.

Calling the Parent Constructor

'super()' is primarily used to invoke the parent class's constructor when creating a new subclass object. It ensures that the parent's initialization code runs before the subclass's own constructor executes.

When 'super()' is called without any arguments, it defaults to calling the parent constructor with no arguments. This is necessary to ensure proper object initialization and setup inherited state.

Example:

class Parent {
    private String name;

    public Parent() {
        name = "Default parent name";
    }
}

class Child extends Parent {
    public Child() {
        super(); // Calls the Parent constructor with no arguments
    }
}

Passing Arguments to the Parent Constructor

'super()' can also be used to pass arguments to the parent constructor. This is useful when the parent constructor has multiple overloaded methods. By specifying specific arguments, you can call the desired parent constructor.

Example:

class Parent {
    private String name;

    public Parent(String name) {
        this.name = name;
    }
}

class Child extends Parent {
    public Child(String name) {
        super(name); // Calls the Parent constructor with a name argument
    }
}

Calling Parent Methods

In addition to invoking the parent constructor, 'super' can also be used to access parent class methods and variables. This allows subclasses to extend or override inherited behavior.

To call a parent method, use the syntax 'super.methodName()'.

Example:

class Parent {
    public void printName() {
        System.out.println("Parent's name: " + name);
    }
}

class Child extends Parent {
    public void printChildName() {
        super.printName(); // Calls the printName() method from the Parent class
    }
}

For detailed tutorials and further explanation, please refer to the provided resource link.

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