Java向api接口发送请求，获取json数据并解析

迈不过友情╰ 2023-06-30 05:28 35阅读 0赞

*  采用的是和风天气的降水接口，因为api需要付费，所以就不把自己的key放出来了。
 *  json解析工具用的是阿里巴巴的fastjson。用了很多次的System.out.println(),只是为了测试。
 *  代码如下：

package json;
    
    import com.alibaba.fastjson.JSONArray;
    import com.alibaba.fastjson.JSONObject;
    
    import java.io.BufferedReader;
    import java.io.InputStream;
    import java.io.InputStreamReader;
    import java.io.PrintWriter;
    import java.net.HttpURLConnection;
    import java.net.URL;
    
    public class Demo2
    {
        
        public static void main(String[] args) throws Exception
        {
        
            //参数字符串，如果拼接在请求链接之后，需要对中文进行 URLEncode   字符集 UTF-8
            String param = "location=108.62 ,21.95&key=写你自己的key";
            StringBuilder sb = new StringBuilder();
            InputStream is = null;
            BufferedReader br = null;
            PrintWriter out = null;
            try {
        
                //接口地址
                String url = "https://api.heweather.net/s6/weather/grid-minute";
                URL    uri = new URL(url);
                HttpURLConnection connection = (HttpURLConnection) uri.openConnection();
                connection.setRequestMethod("POST");
                connection.setReadTimeout(5000);
                connection.setConnectTimeout(10000);
                connection.setRequestProperty("accept", "*/*");
                //发送参数
                connection.setDoOutput(true);
                out = new PrintWriter(connection.getOutputStream());
                out.print(param);
                out.flush();
                //接收结果
                is = connection.getInputStream();
                br = new BufferedReader(new InputStreamReader(is, "UTF-8"));
                String line;
                //缓冲逐行读取
                while ( ( line = br.readLine() ) != null )
                {
        
                    sb.append(line);
                }
                String backStr=sb.toString();
                System.out.println(backStr);
                JSONObject jsonObject = JSONObject.parseObject(backStr);
                JSONArray heWeather6 = jsonObject.getJSONArray("HeWeather6");
                System.out.println(heWeather6);
                JSONObject jsonObject1 = heWeather6.getJSONObject(0);
                System.out.println(jsonObject1);
                JSONObject basic = jsonObject1.getJSONObject("basic");
                System.out.println(basic);
                String parent_city = basic.getString("parent_city");
                System.out.println(parent_city);
                String lon = basic.getString("lon");
                System.out.println(lon);
                String lat = basic.getString("lat");
                System.out.println(lat);
    
                System.out.println("--------------");
                JSONArray pcpn_5m = jsonObject1.getJSONArray("pcpn_5m");
                for (int i = 0; i < pcpn_5m.size(); i++)
                {
        
                    JSONObject jsonObject2 = pcpn_5m.getJSONObject(i);
                    System.out.println(jsonObject2);
    
                }
            } catch ( Exception e )
            {
        
                System.out.println(e);
            } finally
            {
        
                //关闭流
                try
                {
        
                    if(is!=null)
                    {
        
                        is.close();
                    }
                    if(br!=null)
                    {
        
                        br.close();
                    }
                    if (out!=null)
                    {
        
                        out.close();
                    }
                } catch ( Exception ignored )
                {
        
                    System.out.println(ignored);
                }
            }
    
    
        }
    }

*  运行结果如下图：  
    ![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0RlZXBfcm9vdGVk_size_16_color_FFFFFF_t_70]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0RlZXBfcm9vdGVk_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200115123118707.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0RlZXBfcm9vdGVk,size_16,color_FFFFFF,t_70