diff --git "a/01 \350\213\217\346\270\205\345\215\216/20230522 tomcat.md" "b/01 \350\213\217\346\270\205\345\215\216/20230522 tomcat.md"
index cb21c4ade5e2f134a3700e795df2077fc4511c59..ac49dda1d819e6c4725c6c8ff59f2ff4027c3cb2 100644
--- "a/01 \350\213\217\346\270\205\345\215\216/20230522 tomcat.md"	
+++ "b/01 \350\213\217\346\270\205\345\215\216/20230522 tomcat.md"	
@@ -20,7 +20,7 @@ public class DBUtil {
         }
     }
     public static Connection getConn() throws SQLException {
-        Connection conn = DriverManager.getConnection("jadc:mysql://localhost:3306/student_db?useSSL=false&charset=utf8", "root", "root");
+        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/student_db?useSSL=false&useUnicode=true&characterEncoding=utf8", "root", "root");
         return conn;
     }
     public static ResultSet query(String sql,String...keys) throws SQLException {
@@ -58,7 +58,6 @@ public class DBUtil {
 package servlet;
 
 import javax.servlet.ServletException;
-import javax.servlet.annotation.WebServlet;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
@@ -69,127 +68,196 @@ import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 
-@WebServlet("/select")
-public class TestTomcat extends HttpServlet {
+public class Add extends HttpServlet {
     @Override
     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
         resp.setContentType("text/html;charset=utf-8");
-        PrintWriter out = resp.getWriter();
-        Connection conn = DBUtil.getConn();
+        resp.setCharacterEncoding("utf-8");
+        String sql= "insert into student values (5,'李泰容的狗','女')";
+        int i = 0;
         try {
-            PreparedStatement pst = conn.prepareStatement("select * from student");
-            ResultSet rs = pst.executeQuery();
-            out.write("<table border = 1>");
-            out.write("<tr><th>学号</th><th>姓名</th><th>性别</th></tr>");
-            while (rs.next()){
-                out.write("<tr>");
-                out.write("<td>"+rs.getInt("stuId")+"</td><td>"+rs.getString("name")+"</td><td>"+rs.getString("sex")+"</td>");
-                out.write("</tr>");
-            }
-            out.write("<table>");
+            i = DBUtil.update(sql);
         } catch (SQLException e) {
-            throw new RuntimeException(e);
+            e.printStackTrace();
         }
+        if(i>0){
+            resp.getWriter().write("添加成功");
+        }else{
+            resp.getWriter().write("添加失败");
+        }
+
+
     }
 }
+
+```
+
+```java
 package servlet;
 
 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;
-import java.io.PrintWriter;
-import java.sql.Connection;
-import java.sql.PreparedStatement;
 import java.sql.SQLException;
 
-@WebServlet("/insert")
-public class Insert extends HttpServlet {
+public class Delete extends HttpServlet {
     @Override
     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
-        Connection conn = DBUtil.getConn();
+        resp.setContentType("text/html;charset=utf-8");
+        resp.setCharacterEncoding("utf-8");
+        String sql= "delete from student where ssex = '男'";
+        int i = 0;
         try {
-            PreparedStatement pst = conn.prepareStatement("insert into student values (5,'李泰容的狗','女')");
-            int i = pst.executeUpdate();
-            resp.setContentType("text/html;charset=utf-8");
-            PrintWriter out = resp.getWriter();
-            if (i>0){
-                out.write("添加成功");
-            }else {
-                out.write("添加失败");
-            }
+            i = DBUtil.update(sql);
         } catch (SQLException e) {
-            throw new RuntimeException(e);
+            e.printStackTrace();
+        }
+        if(i>0){
+            resp.getWriter().write("删除成功");
+        }else{
+            resp.getWriter().write("删除失败");
         }
     }
+
+    @Override
+    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        super.doPost(req, resp);
+    }
 }
+
+```
+
+```java
 package servlet;
 
 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;
-import java.io.PrintWriter;
-import java.sql.Connection;
-import java.sql.PreparedStatement;
+import java.sql.ResultSet;
 import java.sql.SQLException;
 
-@WebServlet("/update")
-public class Set extends HttpServlet {
+
+public class Select extends HttpServlet {
     @Override
     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
         resp.setContentType("text/html;charset=utf-8");
-        Connection conn = DBUtil.getConn();
+        resp.setCharacterEncoding("utf-8");
+        resp.getWriter().write("<table border=\"1\"><tr>");
+        resp.getWriter().write("<th>id</th><th>姓名</th><th>性别</th></tr>");
         try {
-            PreparedStatement pst = conn.prepareStatement("update student set name = '徐明浩' where stuId = 5");
-            int i = pst.executeUpdate();
-            PrintWriter out = resp.getWriter();
-            if (i>0){
-                out.write("修改成功");
-            }else {
-                out.write("修改失败");
+            String sql="select * from student";
+            ResultSet res = DBUtil.query(sql);
+            while (res.next()){
+                int id = res.getInt(1);
+                String name = res.getString(2);
+                String sex = res.getString(3);
+                resp.getWriter().write("<tr>");
+                resp.getWriter().write("<td>"+id+"</td>");
+                resp.getWriter().write("<td>"+name+"</td>");
+                resp.getWriter().write("<td>"+sex+"</td>");
             }
+            resp.getWriter().write("</tr></table>");
+
         } catch (SQLException e) {
             throw new RuntimeException(e);
         }
     }
+
+    @Override
+    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        super.doPost(req, resp);
+    }
 }
+
+```
+
+```java
 package servlet;
 
 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;
-import java.io.PrintWriter;
-import java.sql.Connection;
-import java.sql.PreparedStatement;
 import java.sql.SQLException;
 
-@WebServlet("/delete")
-public class Delete extends HttpServlet {
+public class Update extends HttpServlet {
     @Override
     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
         resp.setContentType("text/html;charset=utf-8");
-        PrintWriter out = resp.getWriter();
-        Connection conn = DBUtil.getConn();
+        resp.setCharacterEncoding("utf-8");
+        String sql= "update student set sname = '徐明浩' where sid = 5";
+        int i = 0;
         try {
-            PreparedStatement pst = conn.prepareStatement("delete from student where sex = '男'");
-            int i = pst.executeUpdate();
-            if (i>0){
-                out.write("删除成功");
-            }else {
-                out.write("删除失败");
-            }
+            i = DBUtil.update(sql);
         } catch (SQLException e) {
-            throw new RuntimeException(e);
+            e.printStackTrace();
+        }
+        if(i>0){
+            resp.getWriter().write("修改成功");
+        }else{
+            resp.getWriter().write("修改失败");
         }
     }
+
+    @Override
+    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        super.doPost(req, resp);
+    }
 }
+
+```
+
+```java
+<?xml version="1.0" encoding="UTF-8"?>
+<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
+         version="4.0">
+
+
+    <servlet>
+        <servlet-name>add</servlet-name>
+        <servlet-class>servlet.Add</servlet-class>
+
+    </servlet>
+    <servlet>
+        <servlet-name>delete</servlet-name>
+        <servlet-class>servlet.Delete</servlet-class>
+    </servlet>
+    <servlet>
+        <servlet-name>select</servlet-name>
+        <servlet-class>servlet.Select</servlet-class>
+    </servlet>
+    <servlet>
+        <servlet-name>update</servlet-name>
+        <servlet-class>servlet.Update</servlet-class>
+    </servlet>
+
+
+    <servlet-mapping>
+        <servlet-name>add</servlet-name>
+        <url-pattern>/add</url-pattern>
+    </servlet-mapping>
+
+    <servlet-mapping>
+        <servlet-name>delete</servlet-name>
+        <url-pattern>/delete</url-pattern>
+    </servlet-mapping>
+
+    <servlet-mapping>
+        <servlet-name>select</servlet-name>
+        <url-pattern>/select</url-pattern>
+    </servlet-mapping>
+
+    <servlet-mapping>
+        <servlet-name>update</servlet-name>
+        <url-pattern>/update</url-pattern>
+    </servlet-mapping>
+</web-app>
 ```
 
diff --git "a/01 \350\213\217\346\270\205\345\215\216/20230524 \347\275\221\351\241\265\344\277\241\346\201\257\345\206\231\345\205\245\346\225\260\346\215\256\345\272\223.md" "b/01 \350\213\217\346\270\205\345\215\216/20230524 \347\275\221\351\241\265\344\277\241\346\201\257\345\206\231\345\205\245\346\225\260\346\215\256\345\272\223.md"
new file mode 100644
index 0000000000000000000000000000000000000000..72b6b75c76c3680883d8653b0ef355ff2f4c130f
--- /dev/null
+++ "b/01 \350\213\217\346\270\205\345\215\216/20230524 \347\275\221\351\241\265\344\277\241\346\201\257\345\206\231\345\205\245\346\225\260\346\215\256\345\272\223.md"	
@@ -0,0 +1,176 @@
+```java
+import java.sql.*;
+
+public class DBUtil {
+    static{
+        try {
+            Class.forName("com.mysql.jdbc.Driver");
+        } catch (ClassNotFoundException e) {
+            throw new RuntimeException(e);
+        }
+    }
+    public static Connection getConn() throws SQLException {
+        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/student_db?useSSL=false&useUnicode=true&characterEncoding=utf8", "root", "root");
+        return conn;
+    }
+    public static ResultSet query(String sql, String...keys) throws SQLException {
+        Connection conn = getConn();
+        PreparedStatement pre = conn.prepareStatement(sql);
+        for (int i = 0; i < keys.length; i++) {
+            pre.setString((i+1),keys[i]);
+        }
+        ResultSet res = pre.executeQuery();
+        return res;
+    }
+    public static int update(String sql,String...keys) throws SQLException {
+        Connection conn = getConn();
+        PreparedStatement pre = conn.prepareStatement(sql);
+        for (int i = 0; i < keys.length; i++) {
+            pre.setString((i+1),keys[i]);
+        }
+        int i = pre.executeUpdate();
+        return i;
+    }
+    public static void close(Connection conn,PreparedStatement pre,ResultSet res) throws SQLException {
+        if(res!=null){
+            res.close();
+        }if(pre!=null){
+            pre.close();
+        }if(conn!=null){
+            conn.close();
+        }
+    }
+}
+
+```
+
+```java
+import javax.servlet.*;
+import javax.servlet.http.*;
+import javax.servlet.annotation.*;
+import java.io.IOException;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+@WebServlet(name = "Student", value = "/Student")
+public class Student extends HttpServlet {
+    @Override
+    protected void doGet(HttpServletRequest request, HttpServletResponse resp) throws ServletException, IOException{
+        resp.setContentType("text/html;charset=utf-8");
+        resp.setCharacterEncoding("utf-8");
+        resp.getWriter().write("<table border=\"1\"><tr>");
+        resp.getWriter().write("<th>id</th><th>姓名</th><th>性别</th></tr>");
+        try {
+            String sql="select * from student";
+            ResultSet res = DBUtil.query(sql);
+            while (res.next()){
+                int id = res.getInt(1);
+                String name = res.getString(2);
+                String sex = res.getString(3);
+                resp.getWriter().write("<tr>");
+                resp.getWriter().write("<td>"+id+"</td>");
+                resp.getWriter().write("<td>"+name+"</td>");
+                resp.getWriter().write("<td>"+sex+"</td>");
+            }
+            resp.getWriter().write("</tr></table>");
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+
+    }
+
+    @Override
+    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        request.setCharacterEncoding("utf-8");
+        String id = request.getParameter("id");
+        String name = request.getParameter("name");
+        String sex = request.getParameter("sex");
+
+        if (id!=null) {
+            String sql="insert into student values(?,?,?)";
+            response.setContentType("text/html;charset=utf-8");
+            try {
+                int i = DBUtil.update(sql, id, name, sex);
+                if(i>0){
+                    response.getWriter().write("添加成功");
+                }else{
+                    response.getWriter().write("添加失败");
+                }
+            } catch (SQLException e) {
+                throw new RuntimeException(e);
+            }
+        }
+
+        String id1 = request.getParameter("id1");
+        String name1 = request.getParameter("name1");
+
+        if (id1!=null) {
+            String sql="update student set sname=? where sid=? ";
+            response.setContentType("text/html;charset=utf-8");
+            try {
+                int i = DBUtil.update(sql,name1,id1);
+                if(i>0){
+                    response.getWriter().write("修改成功");
+                }else{
+                    response.getWriter().write("修改失败");
+                }
+            } catch (SQLException e) {
+                throw new RuntimeException(e);
+            }
+        }
+
+        String id2 = request.getParameter("id2");
+        if (id2!=null) {
+            String sql="delete from student where sid=? ";
+            response.setContentType("text/html;charset=utf-8");
+            try {
+                int i = DBUtil.update(sql,id2);
+                if(i>0){
+                    response.getWriter().write("删除成功");
+                }else{
+                    response.getWriter().write("删除失败");
+                }
+            } catch (SQLException e) {
+                throw new RuntimeException(e);
+            }
+        }
+
+    }
+
+}
+
+```
+
+```java
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>测试</title>
+</head>
+<body>
+<h1>添加学生</h1>
+<form action="./Student" method="post">
+    学号 <input type="text" name="id"><br>
+    姓名 <input type="text" name="name"><br>
+    性别 <input type="text" name="sex"><br>
+    <input type="submit" value="添加">
+</form>
+
+<h1>修改学生信息</h1>
+<form action="./Student" method="post">
+    学号 <input type="text" name="id1"><br>
+    姓名 <input type="text" name="name1"><br>
+<!--    性别 <input type="text" name="sex1"><br>-->
+    <input type="submit" value="修改">
+</form>
+
+<h1>删除学生</h1>
+<form action="./Student" method="post">
+    请输入需要删除学生的学号<br> <input type="text" name="id2"> <br>
+    <input type="submit" value="删除">
+</form>
+</body>
+</html>
+```
+