MD5加密算法的java實現

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/*


MD5 算法
*/
public class MD5 {
// 全局數組
 private final static String[] strDigits = { "0", "1", "2", "3", "4", "5",

     "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };


public MD5() {
 }
// 返回形式為數字跟字符串
 private static String byteToArrayString(byte bByte) {

 int iRet = bByte;
 // System.out.println("iRet="+iRet);
 if (iRet < 0) {
     iRet += 256;
 }
 int iD1 = iRet / 16;
 int iD2 = iRet % 16;
 return strDigits[iD1] + strDigits[iD2];

}
// 返回形式只為數字
 private static String byteToNum(byte bByte) {

 int iRet = bByte;
 System.out.println("iRet1=" + iRet);
 if (iRet < 0) {
     iRet += 256;
 }
 return String.valueOf(iRet);

}
// 轉換字節數組為16進制字串
 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();

}
public static String GetMD5Code(String strObj) {

 String resultString = null;
 try {
     resultString = new String(strObj);
     MessageDigest md = MessageDigest.getInstance("MD5");
     // md.digest() 該函數返回值為存放哈希值結果的byte數組
     resultString = byteToString(md.digest(strObj.getBytes()));
 } catch (NoSuchAlgorithmException ex) {
     ex.printStackTrace();
 }
 return resultString;

}
public static void main(String[] args) {

 MD5 getMD5 = new MD5();
 System.out.println(getMD5.GetMD5Code("000000"));

}
}</pre>