关于java代码用来实现MD5加密

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**

* MD5加密
* @author wenyuan
*/
public class MD5Encryption {
private final static String[] strDigits = { "0", "1", "2", "3", "4", "5","6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };
private static String byteToArrayString(byte bByte) {
int iRet = bByte;
if (iRet < 0) {
iRet += 256;
}
int iD1 = iRet / 16;
int iD2 = iRet % 16;
return strDigits[iD1] + strDigits[iD2];
}
private static String byteToString(byte[] bByte) {
StringBuffer sBuffer = new StringBuffer();
for (int i = 0; i < bByte.length; i++) {
sBuffer.append(byteToArrayString(bByte[i]));
}
return sBuffer.toString().toUpperCase();
}
public static String toMD5(String strObj) {
String resultString = null;
try {
resultString = new String(strObj);
MessageDigest md = MessageDigest.getInstance("MD5");
resultString = byteToString(md.digest(strObj.getBytes()));
} catch (NoSuchAlgorithmException ex) {
ex.printStackTrace();
}
return resultString;
}
public static void main(String[] args) {
System.out.println(toMD5("40f5888b67c748df7efba008e7c2f9d2"));
}
}