MD5加密之加密字符串

public static String encode(String str) {
String encodeString = "";

try {
MessageDigest md = MessageDigest.getInstance("md5");
// 用MD5加密后的字节数组
byte[] digest = md.digest(str.getBytes());
for (byte b : digest) {
// 将前面的ffffff去掉
int temp = b & 0x000000ff;
// 得到16进制
String s = Integer.toHexString(temp);
// 使每一位上都有两个数
if (s.length() == 1) {
s = "0" + s;
}

encodeString += s;
}
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return encodeString;
}