ขอคำแนะนำในการอ่าน error ของ xcode 5 หน่อยจะเขียน tebleView ที่เชื่อมต่อกับ web Server อ่ะครับ

2014-09-15 20:06:22.697 tableViewJSON[1145:60b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'data parameter is nil'
*** First throw call stack:
(
	0   CoreFoundation                      0x017ed1e4 __exceptionPreprocess + 180
	1   libobjc.A.dylib                     0x0156c8e5 objc_exception_throw + 44
	2   CoreFoundation                      0x017ecfbb +[NSException raise:format:] + 139
	3   Foundation                          0x012b2bd2 +[NSJSONSerialization JSONObjectWithData:options:error:] + 67
	4   tableViewJSON                       0x000027ca -[ViewController viewDidLoad] + 506
	5   UIKit                               0x0034b33d -[UIViewController loadViewIfRequired] + 696
	6   UIKit                               0x0034b5d9 -[UIViewController view] + 35
	7   UIKit                               0x0026b267 -[UIWindow addRootViewControllerViewIfPossible] + 66
	8   UIKit                               0x0026b5ef -[UIWindow _setHidden:forced:] + 312
	9   UIKit                               0x0026b86b -[UIWindow _orderFrontWithoutMakingKey] + 49
	10  UIKit                               0x002763c8 -[UIWindow makeKeyAndVisible] + 65
	11  UIKit                               0x00226bc0 -[UIApplication _callInitializationDelegatesForURL:payload:suspended:] + 2097
	12  UIKit                               0x0022b667 -[UIApplication _runWithURL:payload:launchOrientation:statusBarStyle:statusBarHidden:] + 824
	13  UIKit                               0x0023ff92 -[UIApplication handleEvent:withNewEvent:] + 3517
	14  UIKit                               0x00240555 -[UIApplication sendEvent:] + 85
	15  UIKit                               0x0022d250 _UIApplicationHandleEvent + 683
	16  GraphicsServices                    0x037e2f02 _PurpleEventCallback + 776
	17  GraphicsServices                    0x037e2a0d PurpleEventCallback + 46
	18  CoreFoundation                      0x01768ca5 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 53
	19  CoreFoundation                      0x017689db __CFRunLoopDoSource1 + 523
	20  CoreFoundation                      0x0179368c __CFRunLoopRun + 2156
	21  CoreFoundation                      0x017929d3 CFRunLoopRunSpecific + 467
	22  CoreFoundation                      0x017927eb CFRunLoopRunInMode + 123
	23  UIKit                               0x0022ad9c -[UIApplication _run] + 840
	24  UIKit                               0x0022cf9b UIApplicationMain + 1225
	25  tableViewJSON                       0x00003092 main + 130
	26  libdyld.dylib                       0x01e3470d start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException