Can We Access Child class members in super class in java ?

[kademane guru]

Dear Javaranch,
In java can we access child class members in super class?
if yes give me some examples.


Regards
Kademane Gururaja

[Bhagat Singh Rawat]

kademane guru wrote:Dear Javaranch,
In java can we access child class members in super class?
if yes give me some examples.

No we can't access any members of child class in parent class;

[Jesper de Jong]

You can, but it is not what you want. When your program is designed well, superclasses should not know anything about the internals of their subclasses.

Here is an ugly example, in which I cast this to the subclass type (I recommend that you never do this in a real application, this is just to show that it's possible!):

class Super {
	public void method() {
		System.out.println(((Sub) this).name);
	}
}

class Sub extends Super {
	public String name;

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

Sometimes, however, you might want to create an abstract superclass that leaves some parts to be implemented by subclasses. This version is much better than the example above, because the superclass doesn't need to cast this to a specific subclass type and doesn't need to access the internals of the subclass:

abstract class Super {
	public void method() {
		System.out.println(getName());
	}

	protected abstract String getName();
}

class Sub extends Super {
	private String name;

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

	@Override
	protected String getName() {
		return name;
	}
}