package com.demo;
import java.security.MessageDigest;
public class MD5Util {
private static final String ALGORITHM = "MD5";
private static final char[] HEX_DIGITS = { '0', '1', '2', '3', '4', '5',
'6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
/**
* encode string
*
* @param algorithm
* @param str
* @return String
*/
public static String encode(String algorithm, String str) {
if (str == null) {
return null;
}
try {
MessageDigest messageDigest = MessageDigest.getInstance(algorithm);
messageDigest.update(str.getBytes());
return getFormattedText(messageDigest.digest());
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/**
* encode By MD5
*
* @param str
* @return String
*/
public static String getStringMD5String(String str) {
if (str == null) {
return null;
}
try {
MessageDigest messageDigest = MessageDigest.getInstance(ALGORITHM);
messageDigest.update(str.getBytes());
return getFormattedText(messageDigest.digest());
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/**
* Takes the raw bytes from the digest and formats them correct.
*
* @param bytes
* the raw bytes from the digest.
* @return the formatted bytes.
*/
private static String getFormattedText(byte[] bytes) {
int len = bytes.length;
StringBuilder buf = new StringBuilder(len * 2);
for (int j = 0; j < len; j++) {
buf.append(HEX_DIGITS[(bytes[j] >> 4) & 0x0f]);
buf.append(HEX_DIGITS[bytes[j] & 0x0f]);
}
return buf.toString();
}
public static void main(String[] args) {
System.out.println(MD5Util.getStringMD5String("123"));
}
}
