UTC时间格式有很多，需要辨清自己是属于哪种格式，否则会出错
/* RFC 1123 with 2-digit Year */"EEE, dd MMM yy HH:mm:ss z",/* RFC 1123 with 4-digit Year */"EEE, dd MMM yyyy HH:mm:ss z", /* RFC 1123 with no Timezone */"EEE, dd MMM yy HH:mm:ss", /* Variant of RFC 1123 */"EEE, MMM dd yy HH:mm:ss", /* RFC 1123 with no Seconds */"EEE, dd MMM yy HH:mm z", /* Variant of RFC 1123 */"EEE dd MMM yyyy HH:mm:ss", /* RFC 1123 with no Day */"dd MMM yy HH:mm:ss z", /* RFC 1123 with no Day or Seconds */"dd MMM yy HH:mm z", /* ISO 8601 slightly modified */"yyyy-MM-dd'T'HH:mm:ssZ", /* ISO 8601 slightly modified */"yyyy-MM-dd'T'HH:mm:ss'Z'", /* ISO 8601 slightly modified */"yyyy-MM-dd'T'HH:mm:sszzzz", /* ISO 8601 slightly modified */"yyyy-MM-dd'T'HH:mm:ss z", /* ISO 8601 */"yyyy-MM-dd'T'HH:mm:ssz", /* ISO 8601 slightly modified */"yyyy-MM-dd'T'HH:mm:ss.SSSz", /* ISO 8601 slightly modified */"yyyy-MM-dd'T'HHmmss.SSSz", /* ISO 8601 slightly modified */"yyyy-MM-dd'T'HH:mm:ss", /* ISO 8601 w/o seconds */"yyyy-MM-dd'T'HH:mmZ", /* ISO 8601 w/o seconds */"yyyy-MM-dd'T'HH:mm'Z'", /* RFC 1123 without Day Name */"dd MMM yyyy HH:mm:ss z", /* RFC 1123 without Day Name and Seconds */"dd MMM yyyy HH:mm z", /* Simple Date Format */"yyyy-MM-dd", /* Simple Date Format */"MMM dd, yyyy"};
UTC时间是世界时间，北京时间应在UTC时间+上8小时
public static void main(String[] args) throws Exception{Date date = null;// ISO 8601 slightly modified */"yyyy-MM-dd'T'HH:mm:ss'Z'",SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");// -05-21T08:44:00Z 对应的时间格式 yyyy-MM-dd'T'HH:mm:ss'Z'date = sdf.parse("-05-21T08:44:00Z");System.out.println("UTC时间："+date);Calendar calendar = Calendar.getInstance();calendar.setTime(date);calendar.set(Calendar.HOUR,calendar.get(Calendar.HOUR)+8);SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");Date date1 = calendar.getTime();String date2 = simpleDateFormat.format(calendar.getTime());System.out.println("北京时间："+date2);}
