接口調用：從第三方接口獲取數據

1.環境： 系統框架：springboot，實現流程：controller→service

2.接口需求描述：

　 

2. 代碼示例

　2.1 .Controller層

@PostMapping("/vehicleSync")
@PassToken
public BaseResponse VehicleSync(){
    return carsyncService.VehicleSync();
}

　2.2 Service層

public BaseResponse VehicleSync() {
    //定義接口路徑
    String apiUrl = "http://159.138.243.117:30000/app/get-vehilce-list/";
    //接口參數
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    String time = sdf.format(new Date());
    //定義一個JSONObject類型的rets用於接收返回的JSON數據
    Map<String, Object> postData = Maps.newHashMap();
    postData.put("updateTime", time);
    JSONObject rets = postData(apiUrl, JSONObject.toJSONString(postData));
    if (ObjectUtils.isEmpty(rets)) {
        return new BaseResponse(ResponseEnum.ERROR.getCode(), "Interface get parameter error");
    }
    //保存此條數據,框架是springboot，所以有Repository。不要生搬硬套代碼
    String Code = (String) rets.get("code");
    if (ObjectUtils.isEmpty(Code)) {
        //調用成功
        JSONArray jsonArray = rets.getJSONArray("data");
        //用一個集合接收返回的json數據中的data的值，遍歷集合，取出數據
        for (int i = 0, len = jsonArray.size(); i < len; i++) {
            JSONObject jsonObject2 = (JSONObject) jsonArray.get(i);
            VehicleSyncRequest request = new VehicleSyncRequest();
            request.setLicensePlate(jsonObject2.get("licensePlate").toString());
            request.setFuelType(jsonObject2.get("fuelType").toString());
            request.setDeviceNo(jsonObject2.get("deviceNo").toString());
            request.setSimNo(jsonObject2.get("simNo").toString());
            request.setUpdateTime(jsonObject2.get("updateTime").toString());
            request.setGuid(jsonObject2.get("guid").toString());
            if (!isexistVehicle(request)) {
                log.error("Failed to add new vehicle", request.getLicensePlate());
                continue;
            }
        }
    } else {
        return new BaseResponse(ResponseEnum.ERROR);
    }
    return new BaseResponse(ResponseEnum.SUCCESS);
}

public static JSONObject postData(String urls, String jsonObject) {
    try {
        /* 創建一個HttpClient最新版的實現類CloseableHttpClient */
        CloseableHttpClient httpClient = HttpClients.createDefault();
        //接口參數
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String time = sdf.format(new Date());
        /* 創建post方法請求對象，並把拼接好的地址url賦值給它的請求參數urls */
        HttpPost httpPost = new HttpPost(urls);
        StringEntity stringEntity = new StringEntity(jsonObject, "UTF-8");
        httpPost.setEntity(stringEntity);
        httpPost.addHeader("X-Build-Number", "100");
        httpPost.addHeader("X-App-Version", "1.0.0");
        httpPost.addHeader("X-Device-System-Info", "HWC");
        httpPost.addHeader("X-Device-Type", "linux");
        httpPost.addHeader("X-Language-Code", "en");
        httpPost.addHeader("X-Time-Stamp", time);
        /* 設置報文頭為Content-Type。具體格式看實際需求，我只知道如果請求的數據包為raw時，用Content-Type */
        httpPost.addHeader("Content-Type", "application/json");
        //執行請求操作，並拿到結果（同步阻塞）。（括號里的同步阻塞我也不知道什么意思，之后知道了再補上）
        /* 設置參數到請求對象中 */
        CloseableHttpResponse response = httpClient.execute(httpPost);
        log.info(response.toString());
        /* 獲取結果實體 */
        HttpEntity entity = response.getEntity();
        /* 看返回狀態是否正常，正常則把獲取到的json字符串返回給調用者 */
        int statue = response.getStatusLine().getStatusCode();
        if (statue != HttpStatus.SC_OK) {
            log.error("http connect fail:{}", response.getStatusLine());
        }
        //返回結果
        String result = EntityUtils.toString(entity, "utf-8");
        log.info(result);
        return JSON.parseObject(result);
    } catch (Exception e) {
        log.error(e.toString());
        return JSON.parseObject(null);
    }
}

3. 設置header/body參數請求

3.1 創建header參數

HttpPost httpPost = new HttpPost(urls);
   httpPost.setEntity(stringEntity);
   httpPost.addHeader("X-Build-Number", "100");
   httpPost.addHeader("X-App-Version", "1.0.0");
   httpPost.addHeader("X-Device-System-Info", "HWC");       
   httpPost.addHeader("Content-Type", "application/json");        
   CloseableHttpResponse response = httpClient.execute(httpPost);

3.2 創建body參數

HttpPost httpPost = new HttpPost(urls);
httpPost.setHeader("Content-Type", "application/json");
JSONObject inner = new JSONObject();
inner.put("X-Build-Number", "100");
inner.put("X-App-Version", "1.0.0");
inner.put("X-Device-System-Info", "HWC");　
JSONObject param = new JSONObject();
param.put("HttpHeader", inner.toString());
httpPost.setEntity( new StringEntity(param.toString()));
CloseableHttpResponse response = httpClient.execute(httpPost);

4. 拉取依賴　

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.2</version>
</dependency>　

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.2.4</version>
</dependency>

<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpcore</artifactId>
    <version>4.4.11</version>
</dependency>