public boolean isIP(String addr)
    {
      if(addr.length() < 7 || addr.length() > 15 || "".equals(addr))
      {
        return false;
      }
      /**
       * 判断IP格式和范围
       */
      String rexp = "([1-9]|[1-9]\\d|1\\d{2}|2[0-4]\\d|25[0-5])(\\.(\\d|[1-9]\\d|1\\d{2}|2[0-4]\\d|25[0-5])){3}";
      Pattern pat = Pattern.compile(rexp);
      Matcher mat = pat.matcher(addr);
      boolean ipAddress = mat.find();
      //============对之前的ip判断的bug在进行判断
      if (ipAddress==true){
        String ips[] = addr.split("\\.");
        if(ips.length==4){
            try{
              for(String ip : ips){
                if(Integer.parseInt(ip)<0||Integer.parseInt(ip)>255){
                  return false;
                }
              }
            }catch (Exception e){
              return false;
            }
          return true;
        }else{
          return false;
        }
      }
      return ipAddress;
    }
}