接口的http請求，獲取json數據格式的工具類HttpPost

接口的http請求，獲取json數據格式的工具類

工具類HttpPost

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

public class HttpPost
{
  public static String httpUrlConnectionPost(String startTime, String endTime, String scenicIds)
  {
    String POST_URL = "http://111.197.19.111:8001/zxcvfg-ertw-service/v1/scenics/analysis";
    String result = null;
    try {
      URL url = new URL(POST_URL);

      HttpURLConnection connection = (HttpURLConnection)url.openConnection();

      connection.setDoOutput(true);

      connection.setDoInput(true);

      connection.setRequestMethod("POST");

      connection.setUseCaches(false);

      connection.setInstanceFollowRedirects(true);

      connection.setRequestProperty("Content-Type", "application/json;charset=utf-8");

      connection.connect();

      DataOutputStream dataOutputStream = new DataOutputStream(connection.getOutputStream());

      String data = new StringBuilder().append("{ \"dayRange\": { \"end\": \"").append(endTime).append("\", \"start\": \"").append(startTime).append("\" }, ").append("\"dimensions\": [ ").append("\"provinceSourceTop10\" ], \"scenicIds\": [").append(scenicIds).append("]}").toString();

      dataOutputStream.writeBytes(data);

      dataOutputStream.flush();
      dataOutputStream.close();

      BufferedReader bf = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));

      StringBuilder sb = new StringBuilder();
      String line;
      while ((line = bf.readLine()) != null)
      {
        sb.append(line).append(System.getProperty("line.separator"));
      }
      bf.close();
      connection.disconnect();

      result = sb.toString();
    } catch (IOException e) {
      e.printStackTrace();
    }
    return result;
  }
}

DataOutputStream.writeBytes()特別解析

DataOutputStream dataOutputStream = new DataOutputStream(connection.getOutputStream());
String data = new StringBuilder().append("{ \"dayRange\": { \"end\": \"").append(endTime).append("\", \"start\": \"").append(startTime).append("\" }, ").append("\"dimensions\": [ ").append("\"provinceSourceTop10\" ], \"scenicIds\": [").append(scenicIds).append("]}").toString();
dataOutputStream.writeBytes(data);
dataOutputStream.flush();
dataOutputStream.close();

java.io.DataInputStream.writeBytes(String s) 方法寫入一個字節到底層流爲1個字節的值。成功執行此方法該計數器加1遞增。
其中dataOutputStream.writeBytes(data)方法的說明：
參數：data -- 源作爲字符串寫入的字節流；返回值：此方法不返回任何值；異常：IOException -- 如果發生I/ O錯誤。