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Message:
Sorry for the long message !! revert back if I have got your question wrong
Posted by Sridhar Visvanath on November 17, 2000 at 1:11 AM
import mylib.*; class Client
{
public static void main(String[]args)
{
InDirectAccess ia = new InDirectAccess();
/* try uncommenting the following line and you will get a compile-time error
that you can't access the class because DirectAccess is not a public class and
a package class and hence available only within its package.
The public int in DirectAccess carries any meaning
only if the class to which it belongs , in this case DirectAccess , has a public access,
which is not true as DirectAccess is available only within it's package mylib
The access specifiers for classes supersedes that of its variables.
When you cannot enter a country (say USA) how will you be able to
enter a city (say Buffalo) in that country.
similarly
When you cannot enter a class (DirectAccess) how will you be able to
access it variable (Integer var ) in that class.
You can say that Buffalo is inaccessible inside USA even though the other parts of the
USA are accessible by saying that Buffalo is private .
similarly had your class DirectAccess been available to the Client , then
you can prevent them from accessing the Integer var by making that var private
You can however access a ref obj to the DirectAcces from the InDirectAccess because
the IndirectAccess is public and the obj var is not private / protected / default
but public.
*/
//DirectAccess da = new DirectAccess();
}
}
> //DirectAccess.java
> package mylib;
> class DirectAccess {
> public Integer var = new Integer(10);
> } > ------------------------------------------------------ > //IndirectAccess.java
> package mylib; > public class IndirectAccess {
> public DirectAccess obj= new DirectAccess();
> } > ------------------------------------------------------ > //client.java
> import mylib.*; > class client {
> public static void main(String arg[]) {
> IndirectAccess ia = new IndirectAccess();
> System.out.println(ia.obj.var);
> }
> } > ------------------------------------------------------ > compile client.java, got complaint: > client.java:6: The type mylib.DirectAccess to which the member var belongs is
> not accessible from class client.
> System.out.println(ia.obj.var);
> ^
> 1 error >
> MY QUESTION IS: > in class DirectAccess: wheather var is public or default doesn't make any difference, why wouldn't compiler
> complain about this, because if there is no way for any class outside mylib package to access "var", then
> its modifier "public" only cause confusion. > Thanks,
> John
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