Can someone explain this behaviour?Is it a bug or I am missing something obvious?
1)Create 2 packages, say pack1 and pack2 in same directory.
2)In pack1 create a class X
package pack1;
import pack2.*;
public class X
{
void eat()
{
System.out.println("X eat");
}
public static void main(String args[])
{
X x = new Y();
x.eat(); //accessing eat() method on Instance of Y.
//But since eat() is not public or protected its visibility must be limited to class X
System.out.println("Done");
}
}
3)Now in pack2 create a class Y
package pack2;
import pack1.*;
public class Y extends X
{
}
The method eat shouldn't be available to class Y as it has 'default' access specifier which limits its visibility to the package it is declared (Package X). So, this method shouldn't be available in class Y. But When I compile and Execute this code, it works fine. Isn't its a violation of 'default' access specifier?
Also If I change X x = new Y() to Y x = new Y(), then compilation fails!!
[EDIT]
1) The method eat shouldn't be available to class Y as it has 'default' access specifier which limits its visibility to the package it is declared (Package X). So, this method shouldn't be available in class Y.
Answer: You are not accessing the eat method of Y, you are accessing the eat method of X. Moreover, you are invoking it from main method of X which means it is visible (the call is within package pack1).
Move the code:
public static void main(String args[])
{
X x = new Y();
x.eat();
System.out.println("Done");
}
from class X (in pack1) to class Y (in pack2) to see that eat() is no longer accessible. You will receive the compiler error message
The method eat() from the type X is not visible
2) Also If I change X x = new Y() to Y x = new Y(), then compilation fails!!
Answer: Because, like before, the method you are accessing is not in class Y but class X. As the eat() method has the default access modifier, it is not available via inheritance. So, as the variable is now of type Y (not X), you can no longer access this method.