项目搭建

pom文件引入依赖与打包配置。

<dependencies><!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api --><dependency><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>3.1.0</version><scope>provided</scope></dependency><!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind --><dependency><groupId>com.fasterxml.jackson.core</groupId><artifactId>jackson-databind</artifactId><version>2.16.2</version></dependency></dependencies><packaging>war</packaging><build><finalName>hello</finalName></build>

目录结构创建。

web.xml写入配置。

<!DOCTYPE web-app PUBLIC"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN""http://java.sun.com/dtd/web-app_2_3.dtd" >
<web-app></web-app>

idea配置tomcat。

接口使用

import com.fasterxml.jackson.databind.json.JsonMapper;import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;@WebServlet("/test")
public class HelloServlet extends HttpServlet {long count = 0;@Overridepublic void init() throws ServletException {new Thread(() -> {while (true) {count++;try {Thread.sleep(1000);} catch (InterruptedException e) {e.printStackTrace();}}}).start();}@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {String username = req.getParameter("username");String password = req.getParameter("password");System.out.println("username = " + username + ", password = " + password);resp.setContentType("text/html; charset=utf8");resp.setStatus(200);resp.setHeader("refresh", "1");resp.getWriter().write("success " + count);}static class Customer {public String username;public String password;}static class ResponseMessage {public Integer status;}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {JsonMapper jsonMapper = new JsonMapper();// 入参映射转换
//        Customer customer = jsonMapper.readValue(req.getInputStream(), Customer.class);// 读取入参报文StringBuilder request = new StringBuilder();// 读取方式一
//        String line;
//        while ((line = req.getReader().readLine()) != null) {
//            request.append(line);
//        }// 读取方式二byte[] requestBuffer = new byte[1024];int length;while ((length = req.getInputStream().read(requestBuffer, 0, requestBuffer.length)) > 0) {request.append(new String(requestBuffer, 0, length));}// 组织出参报文resp.setContentType("application/json; charset=utf8");resp.setStatus(200);ResponseMessage responseMessage = new ResponseMessage();responseMessage.status = 200;String response = jsonMapper.writeValueAsString(responseMessage);resp.getWriter().write(response);System.out.println("request: " + request + "\n" + "response: " + response);}
}