T
Tony Morris
duff said:
Not much can be said, but welcome to Sun documentation
--
Tony Morris
http://tmorris.net/
Java Questions and Answers
http://jqa.tmorris.net/
Not much can be said, but welcome to Sun documentation
--
Tony Morris
http://tmorris.net/
Java Questions and Answers
http://jqa.tmorris.net/
D
duff
def: Local Classes - a class which is local to a block of code -
typically within a method - and is not a member of the enclosing
class.
ok, I read somewhere that local classes (like local variables) can't
have access modifiers? Is this correct? If yes then what's with this
example:
http://java.sun.com/docs/books/tutorial/java/javaOO/innerclasses.html
(scroll to the end)
typically within a method - and is not a member of the enclosing
class.
ok, I read somewhere that local classes (like local variables) can't
have access modifiers? Is this correct? If yes then what's with this
example:
http://java.sun.com/docs/books/tutorial/java/javaOO/innerclasses.html
(scroll to the end)
R
Roedy Green
have you tried compiling it or something similar? The tutorial might
have been written before the language spec was nailed down.
D
duff
Compile time error with that example.
It must be quite recent as generics was used on that page.
R
Roedy Green
Not much can be said, but welcome to Sun documentation
You can file a "bug" report in the Sun bug parade (images of marching
ladybugs carrying parasols) to get the documentation fixed too.
See http://mindprod.com/jgloss/bugs.html
S
Stefan Schulz
duff said:
Did you replace the ... parts with appropriate "null" returns? If i do
that, it compiles fine for me.
Also note that the StackIterator class is not a local class, but an
inner class of Stack. If it where a local class the code would look
like this:
public class Stack {
private ArrayList<Object> items;
//code for Stack's methods and constructors
//not shown
public Iterator<Object> iterator() {
class StackIterator implements Iterator {
int currentItem = items.size() - 1;
public boolean hasNext() {
return false; // implement!
}
public ArrayList<Object> next() {
throw new NoSuchElementException // implement!
}
public void remove() {
throw new UnsupportedOperationException();
}
}
return new StackIterator();
}
}
M
Mike Schilling
duff said:
That's not a local class; it's an inner class. Local classes are defined
within method bodies and are visible only to the method that contains them,
so an access modifier makes no sense. An inner class (like this one) could
be visible to the world, if it's public and its containing class is public,
so limiting its access does make sense.
D
duff
Yup, just like your example below did.
hmm... but StackIterator is in a method, doesn't that make it a local
class - ie. not a member of the enclosing class?
Yup, all because of the missing "private" access modifier.
S
Stefan Schulz
duff said:
It seems you are confused about the types of classes. Let me try to
illustrate things a bit further. Paste the following into a file called
Example.java:
public class Example {
/* a public toplevel class */
private class Nested {
/* this is a nested class. It may have any access modifier */
}
public void foo() {
class Local {
/* this is a local class, and may not have any access
* modifiers
*/
}
new Object(){
/* this is an anonymous class, which can not have any access
* modifier (and not even a name)
*/
}
}
}
class AnotherToplevel {
/* this is another toplevel class.
* The only legal modifier is public, but only if the class is
* declared in a file matching its name.
*/
}
D
Daniel Dyer
He's not confused, the example is broken, it has a local class with a
private modifier and doesn't compile unless you remove it. You might not
be looking at the same bit he's talking about, it's the very last section
of code, just above "Other Facts about Nested Classes".
Dan.
S
Stefan Schulz
Daniel said:
The last paragraph is correct. The example before it, however... my
guess is they meant to put the "StackIterator" class outside the
method. Definitly worth fixing, though.