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#import "NSURL+CheckURL.h"
#import <objc/message.h>

@implementation NSURL (CheckURL)

+ (void)load
{
    // get methos name
    Method urlMethod = class_getClassMethod([NSURL class], @selector(URLWithString:));
    Method newUrlMethod = class_getClassMethod([NSURL class], @selector(new_URLWithString:));
    // swap methods
    method_exchangeImplementations(urlMethod, newUrlMethod);
}

+ (instancetype)new_URLWithString:(NSString *)URLString
{
    NSURL *url = [NSURL dd_URLWithString:URLString];
    if (!url) {
        NSLog(@"url is nil");
    }
    return url;
}

@end