java消息摘要算法加密

package michael.utils;
 
import java.security.MessageDigest;
 
/**
 * blog www.micmiu.com
 *
 * @author Michael
 *
 */
public class EncoderHandler {
 
 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 encodeByMD5(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);
 // 把密文转换成十六进制的字符串形式
 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("111111 MD5  :"
 + EncoderHandler.encodeByMD5("111111"));
 System.out.println("111111 MD5  :"
 + EncoderHandler.encode("MD5", "111111"));
 System.out.println("111111 SHA1 :"
 + EncoderHandler.encode("SHA1", "111111"));
 }
 
}

运行结果如下：

111111 MD5  :96e79218965eb72c92a549dd5a330112
111111 MD5  :96e79218965eb72c92a549dd5a330112
111111 SHA1 :3d4f2bf07dc1be38b20cd6e46949a1071f9d0e3d

转载自： micmiu – 软件开发+生活点滴
http://www.micmiu.com/lang/java/java-md5-sha1/