java对远程url地址进行访问并获取返回的数据

 /**
     * url-天气
     */
    public static void main(String[] args){
        String url = "https://free-api.heweather.com/s6/weather/now";
        String key = "xxx";
        String parms = "location=深圳&key="+key;
        String str = SendGET(url,parms);
        System.err.print(str);
    }
    public static String SendGET(String url,String param){
        String result="";//访问返回结果
        BufferedReader read=null;//读取访问结果
        try {
            //创建url
            URL realurl=new URL(url+"?"+param);
            //打开连接
            URLConnection connection=realurl.openConnection();
            // 设置通用的请求属性
            connection.setRequestProperty("accept", "*/*");
            connection.setRequestProperty("connection", "Keep-Alive");
            connection.setRequestProperty("user-agent",
                    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
            //建立连接
            connection.connect();
            // 获取所有响应头字段
            Map> map = connection.getHeaderFields();
            // 遍历所有的响应头字段，获取到cookies等
            for (String key : map.keySet()) {
                System.out.println(key + "--->" + map.get(key));
            }
            // 定义 BufferedReader输入流来读取URL的响应
            read = new BufferedReader(new InputStreamReader(
                    connection.getInputStream(),"UTF-8"));
            String line;//循环读取
            while ((line = read.readLine()) != null) {
                result += line;
            }
        } catch (IOException e) {
            e.printStackTrace();
        }finally{
            if(read!=null){//关闭流
                try {
                    read.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return result;
    }