[RFC][plugin]: fix fixme

[Andrew Su]

----- Original Message -----
> > Are we not worried about the identifiers going into negatives?
> 
> At first I didn't think this would be possible without running
> out of memory first, but looking at it again, you're right - in
> very rare cases it is possible to not run out of memory and still
> have that function return a negative number (but none of these
> cases are possible right now, since we don't really dereference
> anything). Still, it's good to guard against all possibilities.
> 
> I've attached the improved patch.
> 
> Regards,
> Denis.

-- snip --

+    private static boolean checkNeg() {
+        if (nextUniqueIdentifier < 1) {
+            wrapped = true;
+            nextUniqueIdentifier = 1;
+        }
+        return wrapped;
+    }
+    private int getNextID() {
+        // TODO: we may want to count the number of iterations in this
+        // loop. If we're wasting too much time there, throw some error
+        // to indicate that we need to switch to longs.
+        while (checkNeg() && objects.containsKey(nextUniqueIdentifier))
+            nextUniqueIdentifier++;
+        return nextUniqueIdentifier++;
+    }


In getNextID, I think you're going to be incrementing it by 1 extra. 

pretend max int = 6
id in use: 1 2 3 4 5 6

nextUniqueIdentifier = 1
once it reaches 6 in use it wraps.
3 gets dereferenced before we reach it.
1 2 4 5 6
you get to 2...
checkNeg() = true, containsKey = true
id++; // id is now 3
checkNeg = true, containsKey = false
return id++;  // we have now made id = 4 but 4 is in use

-- Andrew