Question

我是android的初学者，我试图调用simple weather api来返回JSON响应。

我想知道进行api调用的有效方法是什么，以及从哪里学习这些方法。

我尝试使用Jackson实现它：

WebService.java （从某个链接复制粘贴）

public class WebService {

    public <T> T get(String url, T object) throws Exception {
        RestTemplate restTemplate = new RestTemplate();
        HttpHeaders headers = new HttpHeaders();
        headers.set("x-system-code", "mobile");
        headers.set("x-server-api-password", "mobile");
        headers.set("x-server-api-key", "mobile");
        headers.set("Connection", "Close");
        HttpEntity entity = new HttpEntity("parameters", headers);
        restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());
        return (T) restTemplate.exchange(url, HttpMethod.GET, entity, object.getClass()).getBody();
    }

    public <T> T get(String url, T object, Map uriVariables) throws Exception {
        RestTemplate restTemplate = new RestTemplate();
        HttpHeaders headers = new HttpHeaders();
        headers.set("Connection", "Close");
        HttpEntity entity = new HttpEntity("parameters", headers);
        restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());
        return (T) restTemplate.exchange(url, HttpMethod.GET, entity, object.getClass(), uriVariables).getBody();
    }


    public <T> T post(String url, Object request, T object) throws Exception {
        RestTemplate restTemplate = new RestTemplate();
        HttpHeaders headers = new HttpHeaders();
        headers.set("x-system-code", "mobile");
        headers.set("x-server-api-password", "mobile");
        headers.set("x-server-api-key", "mobile");
        headers.set("Connection", "Close");
        HttpEntity entity = new HttpEntity(request, headers);
        restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());
        return (T) restTemplate.exchange(url, HttpMethod.POST, entity, object.getClass()).getBody();
    }

    public void put(String url, Object request) {
        try {
            RestTemplate restTemplate = new RestTemplate();
            restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());
            restTemplate.put(url, request);

        } catch (Exception e) {
            Log.e("WebService - put", e.getMessage(), e);
        }
    }

    public void delete(String url, Object request) {
        try {
            RestTemplate restTemplate = new RestTemplate();
            restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());
            restTemplate.delete(url);
        } catch (Exception e) {
            Log.e("WebService - delete", e.getMessage(), e);
        }
    }
}`

MainActivity.java

public class MainActivity extends AppCompatActivity {

    WebService webService=new WebService();
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        GetWeather getWeather=new GetWeather();
        getWeather.execute();

    }

    public class GetWeather extends AsyncTask<URL, Integer, response>{

        String url;
        public GetWeather(){
            url="http://api.openweathermap.org/data/2.5/weather?q=Gurgaon&units=metric&appid=94d605bef2c15307c23f65a326d*****";
        }


        @Override
        protected void onPreExecute() {
            super.onPreExecute();
        }
        @Override
        protected response doInBackground(URL... params) {
            try {
                response weatherResponse= webService.get(url,new response());
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(response response) {
            super.onPostExecute(response);
            Log.i("response", response.toString());
        }
    }
}

错误

org.springframework.web.client.ResourceAccessException：I / O错误：连接上的意外流结束{api.openweathermap.org：80，proxy = DIRECT hostAddress = 128.199.109.89 cipherSuite = none protocol = http / 1.1} （回收计数= 0）;嵌套异常是java.io.IOException：连接上的意外结束流{api.openweathermap.org：80，proxy = DIRECT hostAddress = 128.199.109.89 cipherSuite = none protocol = http / 1.1}（recycle count = 0） 01-04 07：21：51.536 21098-21137 / com.example.rajatgupta.weatherapp W / System.err：at org.springframework.web.client.RestTemplate.doExecute（RestTemplate.java:491）

请告诉我我做错了什么，或者任何其他方式使API命中。

Answer 1

我建议您在Android开发者网站和整个网络上查看Volley大量优秀教程。

使用示例：

JsonObjectRequest jsonRequest = new JsonObjectRequest(GET, url, null,
        new Response.Listener<JSONObject>() {
            @Override
            public void onResponse(JSONObject response) {

                try {
                    Log.d("JSON", response.toString());
                    //Do something with the data

                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        },
        new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                Log.e("JSON", error.toString());
            }
        });

VolleyRequestQueue.getInstance(getActivity()).addToRequestQueue(jsonRequest);

Answer 2

查看Retrofit，它是一个非常简单和紧凑的前向库，可以帮助您实现REST API的接口。

什么是在Android中进行API调用的高效和优化方法

2 个答案: