java之MD5加密

Posted 2020-10-06 starry

java中用MessageDigest类，可以用来加密MD5。

首先创建一个MessageDigest对象

MessageDigest digest = MessageDigest.getInstance("MD5");

 

调用digest.digest(psd.getBytes());会返回一个16位的字符串，然后使用规定的模板转换为32位即可。

for (byte b : bs) {
                String hexString = Integer.toHexString(b & 0xff);
                if (hexString.length() < 2) {
                    hexString = "0" + hexString;
                }
                stringBuffer.append(hexString);
            }

 

 

完整的代码：

 1 import java.security.MessageDigest;
 2 import java.security.NoSuchAlgorithmException;
 3 
 4 public class Md5Util {
 5 
 6     /**
 7      * @param args
 8      */
 9     public static void main(String[] args) {
10         String psd = "123";
11         encoder(psd);
12     }
13 
14     private static void encoder(String psd) {
15         try {
16             MessageDigest digest = MessageDigest.getInstance("MD5");
17             byte[] bs = digest.digest(psd.getBytes());
18             System.out.println(bs.length);
19             StringBuffer stringBuffer = new StringBuffer();
20             for (byte b : bs) {
21                 String hexString = Integer.toHexString(b & 0xff);
22                 if (hexString.length() < 2) {
23                     hexString = "0" + hexString;
24                 }
25                 stringBuffer.append(hexString);
26             }
27             System.out.println(stringBuffer.toString());
28         } catch (NoSuchAlgorithmException e) {
29             e.printStackTrace();
30         }
31 
32     }
33 
34 }

MD5加密