我们dateFromComponents:用于解析从服务器返回的日期字符串。
在极少数情况下，此调用会崩溃，但我们无法重现该错误。有没有人见过这种堆栈跟踪？
Thread 0:
0 libicucore.A.dylib 0x3b13514e _uprv_asciitolower + 18
1 libicucore.A.dylib 0x3b18757b _uloc_openKeywordList + 291
2 libicucore.A.dylib 0x3b135d7f _uloc_getName + 15
3 libicucore.A.dylib 0x3b135ba7 __ZN3icu6Locale4initEPKca + 175
4 libicucore.A.dylib 0x3b14f359 __ZN3icu6Locale14createFromNameEPKc + 57
5 libicucore.A.dylib 0x3b1b13db __ZN3icu8Calendar11setWeekDataERKNS_6LocaleEPKcR10UErrorCode + 131
6 libicucore.A.dylib 0x3b1b164f __ZN3icu8CalendarC2ERKNS_8TimeZoneERKNS_6LocaleER10UErrorCode + 123
7 libicucore.A.dylib 0x3b1d5857 __ZN3icu17GregorianCalendarC2ERKNS_8TimeZoneER10UErrorCode + 27
8 libicucore.A.dylib 0x3b1d5d7b __ZN3icu17GregorianCalendar18setGregorianChangeEdR10UErrorCode + 163
9 CoreFoundation 0x33728967 __CFCalendarSetupCal + 95
10 CoreFoundation 0x336a5db1 __CFCalendarComposeAbsoluteTimeV + 41
11 CoreFoundation 0x336b70d3 -[__NSCFCalendar dateFromComponents:] + 1139
12 <OurApp> 0x0015d7c5 -[NSString(<ACategory>) parsedDateFromyyyyMMddFormat] + 493
13 <OurApp> 0x000e28ab -[<AnNSOperation> finishedWithData:serverDate:] (<AnNSOperation>.m:154)
14 <OurApp> 0x0009ba87 __49-[<AnotherNSOperation> connectionDidFinishLoading:]_block_invoke (<AnotherNSOperation>.m:283)
15 libdispatch.dylib 0x3b9d0793 _dispatch_call_block_and_release + 11
16 libdispatch.dylib 0x3b9d05db _dispatch_client_callout + 23
17 libdispatch.dylib 0x3b9d3e45 __dispatch_main_queue_callback_4CF + 229
18 CoreFoundation 0x336f01b1 __CFRunLoopRun + 1289
19 CoreFoundation 0x3366323d _CFRunLoopRunSpecific + 357
20 CoreFoundation 0x336630c9 _CFRunLoopRunInMode + 105
21 GraphicsServices 0x3721e33b _GSEventRunModal + 75
22 UIKit 0x3557f2b9 _UIApplicationMain + 1121
23 <OurApp> 0x0006c151 main (main.m:32)
我们还观察到这样的堆栈跟踪：
Thread 20 Crashed:
0 libsystem_kernel.dylib 0x3c4fb350 ___pthread_kill + 8
1 libsystem_c.dylib 0x3c4ae36b _abort + 95
2 libc++abi.dylib 0x3ba56ddf abort_message + 75
3 libc++abi.dylib 0x3ba541cf ___cxa_pure_virtual + 19
4 libicucore.A.dylib 0x3bc02637 __ZN3icu8CalendarC2ERKNS_8TimeZoneERKNS_6LocaleER10UErrorCode + 99
5 libicucore.A.dylib 0x3bc26857 __ZN3icu17GregorianCalendarC2ERKNS_8TimeZoneER10UErrorCode + 27
6 libicucore.A.dylib 0x3bc26d7b __ZN3icu17GregorianCalendar18setGregorianChangeEdR10UErrorCode + 163
7 CoreFoundation 0x34189967 __CFCalendarSetupCal + 95
8 CoreFoundation 0x34106db1 __CFCalendarComposeAbsoluteTimeV + 41
9 CoreFoundation 0x341180d3 -[__NSCFCalendar dateFromComponents:] + 1139
以下是方法：
- (NSDate *)parsedDateFromyyyyMMddFormat
{
NSDateComponents* dateComp = [[NSDateComponents alloc] init];
NSArray *stringParts = [self componentsSeparatedByString:@"-"];
/*
check stringParts validity
...
get years, month & co from "stringParts"
...
set year, month & co on "dateComp"
*/
>>>> THIS LINE CRASHED
NSDate *date = [[[self class] currentCalendar] dateFromComponents: dateComp];
<<<<
return date;
}
+ (NSCalendar *)currentCalendar
{
static NSCalendar *calendar;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
calendar = [NSCalendar currentCalendar];
[calendar setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
[calendar setLocale:[[NSLocale alloc] initWithLocaleIdentifier:@"de_DE"]];
});
return calendar;
}