完成：实验三

homework3/.idea/MarsCodeWorkspaceAppSettings.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="com.codeverse.userSettings.MarscodeWorkspaceAppSettingsState">
+    <option name="ckgOperationStatus" value="SUCCESS" />
+  </component>
+</project>

homework3/.idea/gradle.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="GradleSettings">
+    <option name="linkedExternalProjectsSettings">
+      <GradleProjectSettings>
+        <option name="externalProjectPath" value="$PROJECT_DIR$" />
+        <option name="modules">
+          <set>
+            <option value="$PROJECT_DIR$" />
+          </set>
+        </option>
+      </GradleProjectSettings>
+    </option>
+  </component>
+</project>

homework3/.idea/misc.xml

@@ -1,4 +1,10 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="ExternalStorageConfigurationManager" enabled="true" />
+  <component name="FrameworkDetectionExcludesConfiguration">
+    <file type="web" url="file://$PROJECT_DIR$" />
+  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_17" default="true" project-jdk-name="17" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
 </project>

homework3/.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$/.." vcs="Git" />
+  </component>
+</project>

homework3/src/main/java/com/msksbr/homework3/entity/User.java

@@ -0,0 +1,21 @@
+package com.msksbr.homework3.entity;
+
+public class User {
+
+    private String username;
+    private String password;
+
+    public String getUsername() {
+        return username;
+    }
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public String getPassword() {
+        return password;
+    }
+    public void setPassword(String password) {
+        this.password = password;
+    }
+}

homework3/src/main/java/com/msksbr/homework3/servlet/IndexServlet.java

@@ -0,0 +1,28 @@
+package com.msksbr.homework3.servlet;
+
+import com.msksbr.homework3.entity.User;
+import jakarta.servlet.ServletException;
+import jakarta.servlet.annotation.WebServlet;
+import jakarta.servlet.http.*;
+
+import java.io.IOException;
+
+@WebServlet("/IndexServlet")
+
+public class IndexServlet  extends HttpServlet {
+
+    public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
+       response.setContentType("text/html;charset=UTF-8");
+        HttpSession session = request.getSession();
+        User user=(User)session.getAttribute("user");
+        if(user==null){
+            response.getWriter().print("您还没有登录，请" +
+                    "<a href='/Gradle___com_msksbr___homework3_1_0_SNAPSHOT_war/login.html'>登录</a>");
+        }else {
+            response.getWriter().print("欢迎您，"+user.getUsername()+"！");
+            response.getWriter().print("<a href='/Gradle___com_msksbr___homework3_1_0_SNAPSHOT_war/LogoutServlet'>退出</a>");
+            Cookie cookie = new Cookie("JSESSIONID",session.getId());
+            cookie.setMaxAge(60*30);
+        }
+    }
+}

homework3/src/main/java/com/msksbr/homework3/servlet/LoginServlet.java

@@ -0,0 +1,36 @@
+package com.msksbr.homework3.servlet;
+
+import com.msksbr.homework3.entity.User;
+import jakarta.servlet.ServletException;
+import jakarta.servlet.annotation.WebServlet;
+import jakarta.servlet.http.HttpServlet;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+import java.io.IOException;
+import java.io.PrintWriter;
+
+@WebServlet("/LoginServlet")
+
+public class LoginServlet extends HttpServlet {
+    public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
+        response.setContentType("text/html;charset=UTF-8");
+        String username = request.getParameter("username");
+        String password = request.getParameter("password");
+        PrintWriter pw=response.getWriter();
+
+        if("msksbr".equals(username)&&"123456".equals(password)){
+            User user=new User();
+            user.setUsername(username);
+            user.setPassword(password);
+            request.getSession().setAttribute("user",user);
+            response.sendRedirect("/Gradle___com_msksbr___homework3_1_0_SNAPSHOT_war/IndexServlet");
+        }else {
+            pw.write("用户名或密码错误，请重新登录！");
+        }
+    }
+
+    public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
+        doGet(request, response);
+    }
+}

homework3/src/main/java/com/msksbr/homework3/servlet/LogoutServlet.java

@@ -0,0 +1,21 @@
+package com.msksbr.homework3.servlet;
+
+import jakarta.servlet.ServletException;
+import jakarta.servlet.annotation.WebServlet;
+import jakarta.servlet.http.HttpServlet;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+import java.io.IOException;
+
+@WebServlet("/LogoutServlet")
+
+public class LogoutServlet extends HttpServlet {
+    public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
+        request.getSession().removeAttribute("user");
+        response.sendRedirect("/Gradle___com_msksbr___homework3_1_0_SNAPSHOT_war/login.html");
+    }
+    public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
+        doGet(request, response);
+    }
+}

homework3/src/main/webapp/login.html

@@ -0,0 +1,19 @@
+<!DOCTYPE html>
+<html lang="zh_CN">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>登录</title>
+  </head>
+  <body>
+    <form
+      name="reg"
+      action="http://localhost:18080/Gradle___com_msksbr___homework3_1_0_SNAPSHOT_war/LoginServlet"
+      method="post"
+    >
+      用户名:<input name="username" type="text" /><br />
+      密码:<input name="password" type="password" /><br />
+      <input type="submit" value="提交" /><br />
+    </form>
+  </body>
+</html>