HttpUrlConnection get方式通信

　　　　　　　StringBuffer str=new StringBuffer(URLStr+"?");
            Map<String,Object> requestParamsMap = new HashMap<String, Object>();  
            requestParamsMap.put("type",0);
            Iterator it=requestParamsMap.entrySet().iterator();
            while(it.hasNext()){
                Map.Entry<String,Object> element=(Entry<String, Object>) it.next();
                str.append(element.getKey());
                str.append("=");
                str.append(element.getValue());
                str.append("&");
            }
            if(str.length()>0)
                str.deleteCharAt(str.length()-1);//删除末尾多余的一个&
　　　　　　 try {
                 URL url=new java.net.URL(str.toString());
                 URLConnection connection=url.openConnection();
                 HttpURLConnection con=(HttpURLConnection)connection;
                 con.setDoOutput(false);
                 //get请求能使用缓存
                 con.setUseCaches(true);
                 con.setRequestMethod("GET");
                 con.connect();
                 BufferedReader reader=new BufferedReader(new InputStreamReader(con.getInputStream()));
                 String line=null;
                 String result="";
                 while((line=reader.readLine())!=null){
                     result+=line;
                 }
                 System.out.println(result);
             } catch (Exception e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
         }