Sha256哈希函数在Objective C中生成的哈希字符串比Java中要长。Objective C中会添加额外的零,如何使哈希结果更加合理化?
Objective C:
-(NSString*) sha256:(NSString *)clear{
const char *s=[clear cStringUsingEncoding:NSASCIIStringEncoding];
NSData *keyData=[NSData dataWithBytes:s length:strlen(s)];
uint8_t digest[CC_SHA256_DIGEST_LENGTH]={0};
CC_SHA256(keyData.bytes, keyData.length, digest);
NSData *out=[NSData dataWithBytes:digest
length:CC_SHA256_DIGEST_LENGTH];
NSString *hash=[out description];
hash = [hash stringByReplacingOccurrencesOfString:@" " withString:@""];
hash = [hash stringByReplacingOccurrencesOfString:@"<" withString:@""];
hash = [hash stringByReplacingOccurrencesOfString:@">" withString:@""];
return hash;
}
Java
public static String generateHashString(String data)
{
try {
MessageDigest md = MessageDigest.getInstance("SHA-256");
byte[] dataInBytes = data.getBytes(StandardCharsets.UTF_8);
md.update(dataInBytes);
byte[] mdbytes = md.digest();
StringBuffer hexString = new StringBuffer();
for (int i=0;i<mdbytes.length;i++) {
hexString.append(Integer.toHexString(0xFF & mdbytes[i]));
}
return hexString.toString();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
return null;
}