发送json的代码

package service.WxMessages;import com.alibaba.fastjson2.JSONObject;import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.charset.StandardCharsets;
import java.util.Map;public class tokenSendServlet {public static void main(String[] args) {Map<String, String> tokenAndTime = new WxTokenRead().getTokenAndTime();String token = tokenAndTime.get("token");String time = tokenAndTime.get("time");JSONObject json = new JSONObject();json.put("token", token);json.put("time", time);String urlStr = "servlet/receiverToken";//发送数据的url，我这里发的是servletsendJsonPostRequest(json.toJSONString(), urlStr);}/*** 向指定URL发送JSON数据的POST请求。** @param json   JSON数据字符串* @param urlStr 目标URL字符串*/public static void sendJsonPostRequest(String json, String urlStr) {try {// 创建URL和HttpURLConnectionURL url = new URL(urlStr);HttpURLConnection connection = (HttpURLConnection) url.openConnection();// 设置请求方法为POSTconnection.setRequestMethod("POST");// 设置请求头Content-Type为application/jsonconnection.setRequestProperty("Content-Type", "application/json");// 设置允许输出connection.setDoOutput(true);// 写入JSON数据到请求体try (OutputStream os = connection.getOutputStream()) {byte[] input = json.getBytes(StandardCharsets.UTF_8);os.write(input, 0, input.length);}// 获取响应码int responseCode = connection.getResponseCode();System.out.println("Response Code : " + responseCode);// 关闭连接connection.disconnect();} catch (Exception e) {e.printStackTrace();}}
}

接收json的代码（写的servlet）

package servlet;import com.alibaba.fastjson2.JSONObject;
import dao.HikariConnection;
import jakarta.servlet.*;
import jakarta.servlet.http.*;
import jakarta.servlet.annotation.*;import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.stream.Collectors;@WebServlet(urlPatterns = "/servlet/receiverToken", description = "这里是说明")
public class receiverToken extends HttpServlet {@Overrideprotected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {try {// 设置响应内容类型response.setContentType("text/html;charset=UTF-8");// 读取Postman发送的数据BufferedReader reader = new BufferedReader(new InputStreamReader(request.getInputStream()));String json = reader.lines().collect(Collectors.joining());System.out.println("Received JSON: " + json);// 解析整个JSON对象JSONObject jsonObject = JSONObject.parseObject(json);// 获取各个字段的值String token = jsonObject.getString("token");String time = jsonObject.getString("time");System.out.println("Token: " + token + " Time: " + time);// 更新数据库中的 token 和时间updateTokenAndTime(token, time);} catch (Exception e) {e.printStackTrace();System.out.println("/servlet/receiverToken 接收token和时间失败！json为空");}}@Overrideprotected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {doGet(request, response);}// 更新数据库中的 token 和时间public static int updateTokenAndTime(String token ,String time) {final String sql = "UPDATE wx_token SET token = ?, time = ? WHERE id = ?";int rowsAffected = 0;try {Connection conn = HikariConnection.getInstance(); // 从连接池中获取一个连接PreparedStatement ps = conn.prepareStatement(sql);ps.setString(1, token); // 设置新的 tokenps.setString(2, time); // 获取当前系统时间并设置ps.setInt(3, 1); // 设置要更新的记录的 idrowsAffected = ps.executeUpdate();if (rowsAffected > 0) {
//                System.out.println("Token 和时间更新成功！");} else {
//                System.out.println("Token 和时间更新失败！");}conn.close();} catch (SQLException e) {e.printStackTrace();//log.error("获取数据库连接失败！");} catch (Exception e) {e.printStackTrace();}return rowsAffected;}
}