why a class can't access protected method from another class in the same package,the method is interited from the ohtner class from differnt package?

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junzhang1983@gmail.com - 26 Jan 2008 06:33 GMT

package XX;
class A
{
protected void kk ();
}

package YY;
import XX.A;

class B extends A
{

}

package YY;
class C
{
public void zz()
{
kk(); //why can call B.kk()????
}
}

but if we modify as below:
package YY;
import XX.A;

class B extends A
{
protected void kk ()
{
super.kk();
}
}

why above modify can success?
3ks

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Hal Rosser - 26 Jan 2008 07:47 GMT

> package XX;
> class A
[quoted text clipped - 18 lines]
> }
> }

_________
Because protected keyword gives access to subclasses and other members of
the same package.
And class C is not a subclass and not in package XX.

> but if we modify as below:
> package YY;
[quoted text clipped - 10 lines]
> why above modify can success?
> 3ks

Because B is a subclass of A

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Lew - 26 Jan 2008 17:18 GMT

<junzhang1983@gmail.com> wrote ...

>> package XX;
>> class A
[quoted text clipped - 18 lines]
>> }
>> }

This will not compile. Why does the comment refer to B.kk()? Class B is not
involved in the C invocation at all. C does not have a method kk().

Signature

Lew

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Roedy Green - 28 Jan 2008 02:09 GMT

>why above modify can success?

two things. Please use standard caps conventions when you write code,
especially lower case package names. See
http://mindprod.com/jgloss/codingconventions.html

It makes your code look extremely weird to an eye accustomed to
conformant code.

Next read up on what the various scopes are supposed to do.

See http://mindprod.com/jgloss/scope.html
http://mindprod.com/jgloss/protected.html

Signature

Roedy Green, Canadian Mind Products
The Java Glossary, http://mindprod.com

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why a class can't access protected method from another class in the same package,the method is interited from the ohtner class from differnt package?

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