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| #import <Foundation/Foundation.h>
#import <objc/runtime.h>
@interface TestClass : NSObject
{
int x;
int y;
int z;
}
@property int x;
@property int y;
@property int z;
@end
@implementation TestClass
@synthesize x, y, z;
@end
static NSArray *ClassMethodNames(Class c)
{
NSMutableArray *array = [NSMutableArray array];
unsigned int methodCount = 0;
Method *methodList = class_copyMethodList(c, &methodCount);
unsigned int i;
for(i = 0; i < methodCount; i++)
[array addObject: NSStringFromSelector(method_getName(methodList[i]))];
free(methodList);
return array;
}
static void PrintDescription(NSString *name, id obj)
{
NSString *str = [NSString stringWithFormat:
@"%@: %@\n\tNSObject class %s\n\tlibobjc class %s\n\timplements methods <%@>",
name,
obj,
class_getName([obj class]),
class_getName(object_getClass(obj)),
[ClassMethodNames(object_getClass(obj)) componentsJoinedByString:@", "]];
printf("%s\n", [str UTF8String]);
}
int main(int argc, char **argv)
{
[NSAutoreleasePool new];
TestClass *x = [[TestClass alloc] init];
TestClass *y = [[TestClass alloc] init];
TestClass *xy = [[TestClass alloc] init];
TestClass *control = [[TestClass alloc] init];
[x addObserver:x forKeyPath:@"x" options:0 context:NULL];
[xy addObserver:xy forKeyPath:@"x" options:0 context:NULL];
[y addObserver:y forKeyPath:@"y" options:0 context:NULL];
[xy addObserver:xy forKeyPath:@"y" options:0 context:NULL];
PrintDescription(@"control", control);
PrintDescription(@"x", x);
PrintDescription(@"y", y);
PrintDescription(@"xy", xy);
printf("Using NSObject methods, normal setX: is %p, overridden setX: is %p\n",
[control methodForSelector:@selector(setX:)],
[x methodForSelector:@selector(setX:)]);
printf("Using libobjc functions, normal setX: is %p, overridden setX: is %p\n",
method_getImplementation(class_getInstanceMethod(object_getClass(control),
@selector(setX:))),
method_getImplementation(class_getInstanceMethod(object_getClass(x),
@selector(setX:))));
return 0;
}
|