Question

I have array of NSDistantObject class objects.

NSLog(@"%@", [[saveClassObject objectAtIndex:0] connectionForProxy]);
        NSLog(@"%@", NSStringFromClass([[saveClassObject objectAtIndex:0] class]));
        if ([[saveClassObject objectAtIndex:0] isKindOfClass:[NSDistantObject class]]) {
            NSLog(@"Yes");
        }
        else {
            NSLog(@"NO");
        }  

Output for obove code is

2011-10-20 20:49:58.841 DistributedServer[4239:a0f] (** NSConnection 0x10013ec80 receivePort <CFSocket 0x1001133d0 [0x7fff70289ee0]>{valid = Yes, type = 1, socket = 3, socket set count = 140733193388036,
    callback types = 0x2, callout = __NSFireSocketAccept (0x7fff8254e74a), source = 0x10010abb0,
    run loops = <CFArray 0x10015f930 [0x7fff70289ee0]>{type = mutable-small, count = 4, values = (
    0 : <0x100112870>
    1 : <0x100112870>
    2 : <0x1001126a0>
    3 : <0x1001126a0>
)},
    context = <CFSocket context 0x1002000b0>} sendPort <02010610 1002c323 c0a801ae 00000000 00000000> refCount 3 **)
2011-10-20 20:49:58.842 DistributedServer[4239:a0f] NSDistantObject
2011-10-20 20:49:58.844 DistributedServer[4239:a0f] NO

NSStringFromClass returns saveClassObject array contains NSDistantObject class object. isKindofClass returns No for the same. why?

Answer 1

NSProxy‘s -isKindOfClass: calls forwardInvocation:. It’s intended to test the class of the object the proxy stands in for, not the proxy itself.

• To check if the object you have is a proxy, you might want to use isProxy instead.
• To check the proxy’s class, you could check if it’s class equals [NSDistantObject class] or call isSubclassOfClass:.