java MD5加密（大、小写32位）

1.小写32位

String result = "";
String str = "123456";

MessageDigest md5 = MessageDigest.getInstance("MD5");
md5.update((str).getBytes("UTF-8"));
byte b[] = md5.digest();

int i;
StringBuffer buf = new StringBuffer("");

for(int offset=0; offsetresult = buf.toString().toUpperCase();