get和post调用的泛型形式

get调用，需要的参数都在url里，所以函数所需的参数只需要两个，一个url，一个返回数据。

type为返回数据的类型

    @Autowired
    OkHttpClient okHttpClient;
    @Autowired
    ObjectMapper objectMapper;
    public <T> T getMulti(String url, Class<T> type) {
        T result = null;
        Request request1 = new Request.Builder().url(url).build();
        Response response = null;
        String responseBody = null;
        try {
            response = okHttpClient.newCall(request1).execute();
            responseBody = response.body().string();
            result = objectMapper.readValue(responseBody, type);
        } catch (IOException e) {
            logger.error("错误请求地址:" + url + "错误原因:" + e.getMessage());
        } finally {
            IOUtils.closeQuietly(response);
            return result;
        }
    }

post请求需要三个参数，url，参数的实体类，返回体的类

    public static final MediaType JSON = MediaType.parse("application/json;charset=utf-8");
    public <T extends WeixinBaseResponseDto, TR> T postMulti(String url, TR request, Class<T> type) {
        T result = null;
        Response response = null;
        String json = null;
        try {
            json = JSONObject.toJSONString(request);
            RequestBody requestBody = RequestBody.create(JSON, json);
            Request request1 = new Request.Builder().url(url).post(requestBody).build();
            response = okHttpClient.newCall(request1).execute();
            String responseBody = response.body().string();
            result = objectMapper.readValue(responseBody, type);
        } catch (Exception e) {
            logger.error("错误url：" + url + "错误参数：" + json);
        } finally {
            IOUtils.closeQuietly(response);
            return result;
        }
    }

这两种方法都需要引入

        <dependency>
            <groupId>com.squareup.okhttp3</groupId>
            <artifactId>okhttp</artifactId>
            <version>3.7.0</version>
        </dependency>

还可以用RestTemplate类，这样就不需要多余的引用。

    public <T, TR> T postMult2(String url, TR request, Class<T> type) {

        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(org.springframework.http.MediaType.APPLICATION_JSON_UTF8);
        HttpEntity<TR> httpEntity = new HttpEntity<TR>(request, headers);
        RestTemplate restTemplate = new RestTemplate();
        ResponseEntity<String> responseEntity = restTemplate.postForEntity(url, httpEntity, String.class);
                T result = JSON.parseObject(responseEntity.getBody(), type);
//这里可以删除，up只是为了记录一下
        JSONObject jsonObject = JSONObject.parseObject(responseEntity.getBody());
        JSONObject data = JSONObject.parseObject(jsonObject.getString("data"));
        if (data != null) {
            String ssmn = data.getString("ssmnnumber");
            if (ssmn != null) {
                threadLocal.set(ssmn);
            }
        }
        
        return result;
    }