简略MD5加密

简单MD5加密

public static String Md5(String plainText, int length) {
??try {
???MessageDigest md = MessageDigest.getInstance("MD5");
???md.update(plainText.getBytes());
???byte b[] = md.digest();

???int i;

???StringBuffer buf = new StringBuffer("");
???for (int offset = 0; offset < b.length; offset++) {
????i = b[offset];
????if (i < 0)
?????i += 256;
????if (i < 16)
?????buf.append("0");
????buf.append(Integer.toHexString(i));
???}

???if (length == 16) {
????return buf.toString().substring(8, 24);// 16位的加密
???} else {
????return buf.toString();// 32位的加密
???}
??} catch (NoSuchAlgorithmException e) {
???e.printStackTrace();
??}
??return null;
?}