7.15Java之呼叫API介面傳表單獲取返回資訊

例項

package GoogleTranslateAPI;
​
import com.alibaba.fastjson.JSON;
import org.apache.http.HttpEntity;
import org.apache.http.NameValuePair;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
​
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
​
/**
 * 使用HttpClient類測試翻譯介面
 * @since JDK 1.8
 * @date 2021/07/15
 * @author Lucifer
 */
public class TranslateAPITest {
  //定義介面API地址
  private static final String Url = "";
  /**
   *用HttpClient類下的方法建立POST請求demo
   */
  public static void doPostForm(String url) throws IOException {
    //使用HttpClient建立客戶端
    CloseableHttpClient httpClient = HttpClientBuilder.create().build();
    //建立HttpPost類引用
    HttpPost httpPost = new HttpPost(url);
    /*這個httpPost既是我們的表單*/
    List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
​
    //在List引用裡面新增引數
    nameValuePairs.add(new BasicNameValuePair("trans_data","[{\"custom_index\":1," +
        "\"lang_tgt\":\"zh\"," +
        "\"trans_text\":\"HelloWorld\"}]"));
//     UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(nameValuePairs);
//     httpPost.setEntity(urlEncodedFormEntity);
//     httpClient.execute(httpPost);
​
    //將引數放在請求體裡面傳過去的
    String jsonString = JSON.toJSONString(nameValuePairs);
    StringEntity stringEntity = new StringEntity(jsonString, "UTF-8");
​
    //將entity放入post請求體中
    httpPost.setEntity(stringEntity);
    httpPost.setHeader("Content-Type", "multipart/form-data;charset=utf8");
​
    //響應模型
    CloseableHttpResponse response = null;
    try {
      //由客戶端執行傳送Post請求
      response = httpClient.execute(httpPost);
      //從響應模型中獲得響應實體
      HttpEntity responseEntity = response.getEntity();
      //列印響應狀態
      System.out.println("響應狀態為:" + responseEntity.getContentLength());
      //判斷
      if (responseEntity!=null){
        System.out.println("響應內容長度為:" + responseEntity.getContentLength());
        System.out.println("響應內容為:" + EntityUtils.toString(responseEntity));
       }
     }catch (Exception e){
      System.out.println(e.getMessage());
      e.printStackTrace();
     }finally {
      //關閉資源
      try {
​
        if (httpClient != null) {
          httpClient.close();
         }
        if (response != null) {
          response.close();
           }
         }catch (Exception e){
        System.out.println(e.getMessage());
        e.printStackTrace();
       }
     }
   }
​
  public static void main(String[] args) throws IOException {
    doPostForm(Url);
   }
}
​
 

上面是使用了阿里封裝好的類，下面根據實際的API請求過程寫一個具體的請求方法

package OMSAPI;
​
import org.testng.annotations.Test;
​
import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.charset.StandardCharsets;
​
/**
 * 測試從OMS系統找到的API
 * @since JDK 1.8
 * @date 2021/07/15
 * @author Lucifer
 */
public class OmsRealAPITest {
  /**
   * 首先分析該介面的幾個關鍵資料
   * 1、介面地址:
   * 2、請求方式:POST
   * 3、介面請求頭Content-Type:multipart/form-data--->分割線是----WebKitFormBoundaryvKoqOBacjc8vEEDj
   * 4、介面請求引數:id、name、type(圖片)、lastModifiedDate、size、file(binary)
   */
  //定義換行符
  private static String newLine = "\r\n";
  //定義分隔符
  private static String BOUNDARY = "------WebKitFormBoundaryvKoqOBacjc8vEEDj";
  //定義介面地址
  private static String Url = "";
  //抓取到捕獲的Cookie
  private static String Cookie = "thinkphp_show_page_trace=0|0;" +
      "_ati=9948700605832;" +
      "is_show_search=1;" +
      "users=-5PYsAYAeYYOh41Hi2idlIjgX8y1R6I1RsRb3LW-eDPstfTSSmzqgZOL43PQhRUY_K3yquAsSSIWsk40_rbAGwb-aymNgVPqbSa93YJtw_FTIWmAQj5q8_DRRduMPB1YdckZj8gPGBVo7c4uy3FkidzbcNXjf3aQ8jWPT5v_qyJQACNIcJaUFXfuOfO8sIr-hhz-AN-D2kOJGzFNP33KnwSI7Qb9zvnNGaMbCmS9JORQg6fZFvfdE8hJwY7DAzs17GvK1flYz3JtWXOZWcZ7ifZDbbo9MHT-xRO-QCstZEP2Xlp6ofwQcP6ivcbUAFSyCjsene7l4LuJYKTsoB56uPgoj6VjRCSGWl_jYLt7AO9AV79u7Y0DEd-jTXJfuH35cAdhVzU91EQdd5vEMv1k57b4F9D69pHw2ClujcTmKVkuEQPwof6Jjyh519GIfyiQjTRPXPpwVY0oXrNwTA0cRw;" +
      "think_var=zh-cn;" +
      "PHPSESSID=22d17805dc03a848a02df629ce90ce48;" +
      "thinkphp_show_page_trace=0|0";
  @Test
  public static HttpURLConnection uploadPicture(String picturepath) throws IOException {
    //使用URL類開啟一個URL連線
    URL url = new URL(Url);
    //使用Http開啟該連線
    HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
    //設定請求方式
    httpURLConnection.setRequestMethod("POST");
    //POST請求方式需要開啟輸入流和輸出流
    httpURLConnection.setDoInput(true);
    httpURLConnection.setDoOutput(true);
    //設定無快取
    httpURLConnection.setUseCaches(false);
​
    /*開始設定請求頭引數--->根據介面的請求頭資訊設定*/
    try {
      //設定請求頭引數
      httpURLConnection.setRequestProperty("Connection","keep-alive");
      httpURLConnection.setRequestProperty("Content-Type","multipart/form-data; boundary=" + BOUNDARY);
      httpURLConnection.setRequestProperty("Cookie",Cookie);
      httpURLConnection.setRequestProperty("User-Agent","Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Safari/537.36");
​
      /*製作表單*/
      //建立StringBuilder引用
      StringBuilder stringBuilder = new StringBuilder();
      //依據表單格式進行內容新增
      stringBuilder.append(BOUNDARY);
      stringBuilder.append(newLine);
      //加入Content-Description內容
      stringBuilder.append("Content-Disposition: form-data; name=\"id\";" + newLine + newLine +
          "Content-Disposition: form-data; name=\"name\";" + newLine + newLine +
          "Content-Disposition: form-data; name=\"type\";" + newLine + newLine +
              "Content-Disposition: form-data; name=\"size\";" + newLine + newLine +
          "Content-Disposition: form-data; name=\"file\"; filename=" + "Hello" + newLine + newLine +
          BOUNDARY + "--"
           );
      //引數頭設定完成加兩個換行
      stringBuilder.append(newLine);
      stringBuilder.append(newLine);
​
      //建立引數輸出流
      OutputStream outputStream = new DataOutputStream(httpURLConnection.getOutputStream());
      //將引數頭的資料寫入到輸出流中
      outputStream.write(stringBuilder.toString().getBytes(StandardCharsets.UTF_8));
​
      /*定義資料輸入流，用於讀取圖片*/
      //新建檔案物件引用
      File file = new File(picturepath);
      DataInputStream dataInputStream = new DataInputStream(
          new FileInputStream(file)
       );
      //建立緩衝區
      byte[] bufferOut = new byte[1024*10];
      //首字元
      int bytes = 0;
      //每次讀10KB寫入輸出流
      while ((bytes=dataInputStream.read(bufferOut))!=-1){
        //寫入輸出流
        outputStream.write(bufferOut);
       }
      //換行
      outputStream.write(newLine.getBytes(StandardCharsets.UTF_8)); //因為File的內容是二進位制，所以需要轉成位元流
      //關閉流
      dataInputStream.close();
​
      //定義最後資料分隔線，即加上BOUNDARY再加上--
      //換行+分割線+
      byte[] end_data = (newLine + BOUNDARY + "--").getBytes(StandardCharsets.UTF_8); //二進位制，要轉成位元流
​
      //寫上結尾標識
      outputStream.write(end_data);
      //重新整理緩衝區
      outputStream.flush();
      //關閉輸出流
      outputStream.close();
     }catch (Exception e){
      throw new IOException();
     }finally {
​
     }
​
    return httpURLConnection;
   }
​
  /**
   * 定義BufferedReader輸入流來讀取URL響應
   */
  public static void getURLResponse() throws IOException {
    //使用API呼叫方法獲得httpConnection物件引用
    BufferedReader bufferedReader = new BufferedReader(
        new InputStreamReader(
            uploadPicture("C:/Users/Administrator/Desktop/Test_Work/Test_Picture/staticPicture.jpg").getInputStream()
         )
     );
    //讀取URL響應資訊
    String line;
    while ((line=bufferedReader.readLine())!=null){
      //按行寫入
      System.out.println(line);
     }
   }
​
  public static void main(String[] args) throws IOException {
    getURLResponse();
   }
}