JAVA中MD5加密（MD5工具类）

package utilw;
 
import java.security.MessageDigest;
 
public class MD5 {
  /** MD5 */
  private static final String hexDigIts[] = { "0", "1", "2", "3", "4", "5",
      "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };
 
  /** MD5加密 */
  public static String MD5Encode(String origin, String charsetname) {
    String resultString = null;
    try {
      resultString = new String(origin);
      MessageDigest md = MessageDigest.getInstance("MD5");
      if (null == charsetname || "".equals(charsetname)) {
        resultString = byteArrayToHexString(md.digest(resultString
            .getBytes()));
      } else {
        resultString = byteArrayToHexString(md.digest(resultString
            .getBytes(charsetname)));
      }
    } catch (Exception e) {
    }
    return resultString;
  }
 
  public static String byteArrayToHexString(byte b[]) {
    StringBuffer resultSb = new StringBuffer();
    for (int i = 0; i < b.length; i++) {
      resultSb.append(byteToHexString(b[i]));
    }
    return resultSb.toString();
  }
 
  public static String byteToHexString(byte b) {
    int n = b;
    if (n < 0) {
      n += 256;
    }
    int d1 = n / 16;
    int d2 = n % 16;
    return hexDigIts[d1] + hexDigIts[d2];
  }
 
  public static void main(String[] args) {
    System.out.println(MD5Encode("12345", "utf8"));
  }
}