微博地址url(id)与mid的相互转换 Java版

package step0;


/**
 * 
    * @ClassName: Mid2IdUtil Java版
    * @Description:  新浪uid转url (id转mid)
    * @author zeze
    * @date 2016年4月10日 上午10:49:40 
    *
 */
public class Id2MidUtil {
    public static void main(String[] args) {
        System.out.println(Uid2Mid("Aw8Wrzaes"));
        System.out.println(Mid2Uid("3676608718380816"));//Mid2Id
    }
    private static String[] str62keys = { "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", "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" };

    public static String IntToEnode62(Integer int10) {
        String s62 = "";
        int r = 0;
        while (int10 != 0) {
            r = int10 % 62;
            s62 = str62keys[r] + s62;
            int10 = (int) Math.floor(int10 / 62.0);
        }
        return s62;
    }
    
     //62进制转成10进制
    public static String Str62toInt(String str62)
    {
        long i64 = 0;
        for (int i = 0; i < str62.length(); i++)
        {
            long Vi = (long)Math.pow(62, (str62.length() - i - 1));
            String t = str62.substring(i,i+1);
           
            i64 += Vi * findindex(t);
        }
       // System.out.println(i64);
        return Long.toString(i64);
    }
    
    public static int findindex(String t)
    {
        int index=0;
        for(int i=0;i<str62keys.length;i++)
        {
            if(str62keys[i].equals(t)){
                index=i;
                break;
            }
        }
        return index;
    }
 
     public static String Uid2Mid(String mid)
        {
            String id = "";
            for (int i = mid.length() - 4; i > -4; i = i - 4) //从最后往前以4字节为一组读取URL字符
            {
                int offset1 = i < 0 ? 0 : i;
                int len = i < 0 ? mid.length() % 4 : 4;
                
                String str = mid.substring(offset1, offset1+len);
               // System.out.println(offset1+" "+len+" "+str);
                
                str = Str62toInt(str);
                
                if (offset1 > 0) //若不是第一组，则不足7位补0
                {
                    while (str.length() < 7)
                    {
                        str = "0" + str;
                    }
                }
                id = str + id;
            }

            return id;
        }
    
    
    public static String Mid2Uid(String str10) {
        String mid = "";
        int count = 1 ;
        for (int i = str10.length() - 7; i > -7; i = i - 7) // 从最后往前以7字节为一组读取字符
        {
            int offset = i < 0 ? 0 : i;
            int len = i < 0 ? str10.length() % 7 : 7;
            String temp = str10.substring(offset, offset + len);
            String url =IntToEnode62(Integer.valueOf(temp));
            if(count!=3){//z xghm uXym 生成的链接从右往左的前2组，4位一组，不足4位的补0
                for(int j=0;j<4-url.length();j++){
                    url = "0"+url;
                }
            }
            mid = url+mid;                       
                      count++;
               }
        return mid;
    }
}