Question

code in java:
why this is error?
public class Parent {
protected void sayHi() {
System.out.print("Hi");
}


class Child extends Parent {
public void sayHello() {
System.out.print("Hello");
}
}

public static void main(String[]args){
new Child().sayHi();
}
}

Answer 1

what is your error? I'm assuming because you did protected void sayHI() the protected rights might not be significant for a child.

Answer 2

See the code below:
// this is the Parent class
public class Parent
{
protected void sayHi()
{
System.out.print("Hi");
}
// this is an innerclass ok and it inherits from the outerclass Parent
class Child extends Parent
{
public void sayHello()
{
System.out.print("Hello");
}
}
}
the main method will be like this:
public static void main(String[] args)
{
Parent x = new Parent(); // instantiating a Parent object x
Parent.Child y = x.new Child(); // then we instantiating a Child object y using x
y.sayHi(); // calling the sayHi() method
}
I hope this was useful if I'm wrong correct me.
thanks.

Answer 3

thanks ... that's really helpful :)

Answer 4

Hmmm never seen it that way before.

Answer 5

I know extending the Rectangle class you will get it's methods; however I also know that you cannot access protected methods from other classes. Change protected.

I have done Rectangle2D.Float = new Rectangle2D.Float before.

Answer 6

i see

Answer 7

http://docs.oracle.com/javase/tutorial/java/javaOO/accesscontrol.html

hmm apparently it should work though... Maybe it was because mine wasn't a subclass.... HMm not too sure then.

Answer 8

Okay so I plugged in the code into my IDE and I got a static reference issue.

This code works:


import java.util.Scanner;

/**
*
* @author Konrad
*/
public class JavaApplication12
{
protected void sayHi()
{
System.out.print("Hi");
}


static class Child extends JavaApplication12 {
public void sayHello() {
System.out.print("Hello");
}
}

public static void main(String[]args)
{

Child c = new Child();
c.sayHi();
}
}

Answer 9

The issue was that the child class wasn't static... Not 100% sure on how and where statics are used, but I've never seen this issue... never really did nested classes much either though.