%u6211%u7684%u4e91生成字符串

public String unescape(String src) {
     StringBuffer tmp = new StringBuffer();
     tmp.ensureCapacity(src.length());
     int lastPos = 0, pos = 0;
     char ch;
     while (lastPos < src.length()) {
        pos = src.indexOf("%", lastPos);
        if (pos == lastPos) {
           if (src.charAt(pos + 1) == 'u') {
              ch = (char) Integer.parseInt(src.substring(pos + 2, pos + 6), 16);
              tmp.append(ch);
              lastPos = pos + 6;
           }
           else {
              ch = (char) Integer.parseInt(src.substring(pos + 1, pos + 3), 16);
              tmp.append(ch);
              lastPos = pos + 3;
           }
        }
        else {
           if (pos == -1) {
              tmp.append(src.substring(lastPos));
              lastPos = src.length();
           }
           else {
              tmp.append(src.substring(lastPos, pos));
              lastPos = pos;
           }
        }
     }
     return tmp.toString();
  }
其实这个函数的作用就是把以unicode字符显示的字符串还原成它本来的字符。