整合java短链接生成方法.._JAVA_编程开发_程序员俱乐部

CMyEncrypt.java类
public class CMyEncrypt {
//十六进制下数字到字符的映射数组
private final static String[] hexDigits = {"0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"};
/**把inputString加密*/
    public static String md5(String inputStr){
        return encodeByMD5(inputStr);
    }
    /**
     * 验证输入的密码是否正确
     * @param password 真正的密码（加密后的真密码）
     * @param inputString 输入的字符串
     * @return 验证结果，boolean类型
     */
     public static boolean authenticatePassword(String password,String inputString){
         if(password.equals(encodeByMD5(inputString))){
             return true;
         }else{
             return false;
         }
     }
     /**对字符串进行MD5编码*/
     private static String encodeByMD5(String originString){
         if (originString!=null) {
             try {
                 //创建具有指定算法名称的信息摘要
                 MessageDigest md5 = MessageDigest.getInstance("MD5");
                 //使用指定的字节数组对摘要进行最后更新，然后完成摘要计算
                 byte[] results = md5.digest(originString.getBytes());
                 //将得到的字节数组变成字符串返回 
                 String result = byteArrayToHexString(results);
                 return result;
             } catch (Exception e) {
                 e.printStackTrace();
             }
         }
         return null;
     }
     /**
      * 轮换字节数组为十六进制字符串
      * @param b 字节数组
      * @return 十六进制字符串
      */
      private 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();
      }
      //将一个字节转化成十六进制形式的字符串
      private static String byteToHexString(byte b){
          int n = b;
          if(n<0)
          n=256+n;
          int d1 = n/16;
          int d2 = n%16;
          return hexDigits[d1] + hexDigits[d2];
      }
      public static void main(String[] args) {
CMyEncrypt.md5("http://tech.sina.com.cn/i/2011-03-23/11285321288.shtml");
}
}

Test.java测试类
public class Test {
public static void main(String[] args) {
  // 长连接： http://tech.sina.com.cn/i/2011-03-23/11285321288.shtml
       // 新浪解析后的短链接为： http://t.cn/h1jGSC

       String sLongUrl = " http://tech.sina.com.cn/i/2011-03-23/11285321288.shtml" ; // 3BD768E58042156E54626860E241E999
       String[] aResult = shortUrl (sLongUrl);
       // 打印出结果

       for ( int i = 0; i < aResult. length ; i++) {
           System. out .println( "[" + i + "]:::" + aResult[i]);
       }
    }
    public static String[] shortUrl(String url) {
       // 可以自定义生成 MD5 加密字符传前的混合 KEY
       String key = "yuanj" ;
       // 要使用生成 URL 的字符
       String[] chars = new String[] { "a" , "b" , "c" , "d" , "e" , "f" , "g" , "h" ,
              "i" , "j" , "k" , "l" , "m" , "n" , "o" , "p" , "q" , "r" , "s" , "t" ,
              "u" , "v" , "w" , "x" , "y" , "z" , "0" , "1" , "2" , "3" , "4" , "5" ,
              "6" , "7" , "8" , "9" , "A" , "B" , "C" , "D" , "E" , "F" , "G" , "H" ,
              "I" , "J" , "K" , "L" , "M" , "N" , "O" , "P" , "Q" , "R" , "S" , "T" ,
              "U" , "V" , "W" , "X" , "Y" , "Z"
       };
       // 对传入网址进行 MD5 加密
       String sMD5EncryptResult = ( new CMyEncrypt()).md5(key + url);
       String hex = sMD5EncryptResult;
       String[] resUrl = new String[4];
       for ( int i = 0; i < 4; i++) {
           // 把加密字符按照 8 位一组 16 进制与 0x3FFFFFFF 进行位与运算
           String sTempSubString = hex.substring(i * 8, i * 8 +;
           // 这里需要使用 long 型来转换，因为 Inteper .parseInt() 只能处理 31 位 , 首位为符号位 , 如果不用 long ，则会越界
           long lHexLong = 0x3FFFFFFF & Long.parseLong (sTempSubString, 16);
           String outChars = "" ;
           for ( int j = 0; j < 6; j++) {
              // 把得到的值与 0x0000003D 进行位与运算，取得字符数组 chars 索引
              long index = 0x0000003D & lHexLong;
              // 把取得的字符相加
              outChars += chars[( int ) index];
              // 每次循环按位右移 5 位
              lHexLong = lHexLong >> 5;
           }
           // 把字符串存入对应索引的输出数组
           resUrl[i] = outChars;
       }
       return resUrl;
    }
}