字符串的MD5的32位加密和16位加密

1. import java.security.MessageDigest;
2. import java.util.Locale;
3. public class MD5Util {
4. public static String encode(String content) {
5. try {
6. MessageDigest digest = MessageDigest.getInstance("MD5");
7. digest.update(content.getBytes());
8. return getEncode16(digest);
9. //return getEncode32(digest);
10. } catch (Exception e) {
11. }
12. return null;
13. }
14. /**
15. * 32位加密
16. * @param digest
17. * @return
18. */
19. private static String getEncode32(MessageDigest digest) {
20. StringBuilder builder = new StringBuilder();
21. for (byte b : digest.digest()) {
22. builder.append(Integer.toHexString((b >> 4) & 0xf));
23. builder.append(Integer.toHexString(b & 0xf));
24. }
25. //return builder.toString().toLowerCase(); // 小写
26. //return builder.toString().toUpperCase(); // 大写
27. // java.lang.String.toUpperCase(Locale locale) 方法将在此字符串中的所有字符为大写的规则给定的Locale.
28. //return builder.toString().toUpperCase(Locale.getDefault()); // 大写
29. return builder.toString();
30. }
31. /**
32. * 16位加密
33. * @param digest
34. * @return
35. */
36. private static String getEncode16(MessageDigest digest) {
37. StringBuilder builder = new StringBuilder();
38. for (byte b : digest.digest()) {
39. builder.append(Integer.toHexString((b >> 4) & 0xf));
40. builder.append(Integer.toHexString(b & 0xf));
41. }
42. // 16位加密，从第9位到25位
43. //return builder.substring(8, 24).toString().toUpperCase();
44. return builder.substring(8, 24).toString();
45. }
46. }
47. 参考：http://jiewushanshan.lofter.com/post/cf538_1d903d
48. http://blog.****.net/lincyang/article/details/5709189