From 4bb989787c397823c7b8531238e7af2e566fdc83 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E2=80=9C=E8=82=96=E9=92=9F=E5=87=AF=E9=9F=A9=E2=80=9D?=
 <“3175644391@qq.com”>
Date: Wed, 24 May 2023 23:36:09 +0800
Subject: [PATCH] =?UTF-8?q?=E7=AC=AC=E4=B8=89=E6=AC=A1=E4=BD=9C=E4=B8=9A?=
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Content-Type: text/plain; charset=UTF-8
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---
 .../20230524 Tomcat.md"                       | 165 ++++++++++++++++++
 1 file changed, 165 insertions(+)
 create mode 100644 "22 \350\202\226\351\222\237\345\207\257\351\237\251/20230524 Tomcat.md"

diff --git "a/22 \350\202\226\351\222\237\345\207\257\351\237\251/20230524 Tomcat.md" "b/22 \350\202\226\351\222\237\345\207\257\351\237\251/20230524 Tomcat.md"
new file mode 100644
index 0000000..cb241fd
--- /dev/null
+++ "b/22 \350\202\226\351\222\237\345\207\257\351\237\251/20230524 Tomcat.md"	
@@ -0,0 +1,165 @@
+~~~ java
+// 封装类
+package util;
+
+import java.sql.*;
+
+public class DBUtli {
+    //注册驱动
+    private static String url="jdbc:mysql:///student_db?useSSL=false&characterEncoding=utf8";
+    private static String user="root";
+    private static String password="root";
+
+    static {
+        try {
+            Class.forName("com.mysql.jdbc.Driver");
+        } catch (ClassNotFoundException e) {
+            System.out.println("驱动注册异常！");
+            e.printStackTrace();
+        }
+    }
+    //获取链接方法
+    public static Connection getConn(){
+        Connection conn = null;
+        try {
+            conn = DriverManager.getConnection(url,user,password);
+        } catch (SQLException e) {
+            System.out.println("获取链接失败");
+            e.printStackTrace();
+        }
+        return conn;
+    }
+    //通用查询方法
+    public static ResultSet query(String sql,String ...keys){
+        //获取链接对象
+        Connection conn = getConn();
+        ResultSet rst = null;
+        try {
+            PreparedStatement pst = conn.prepareStatement(sql);
+
+            for (int i = 0; i < keys.length; i++) {
+                pst.setString((i+1),keys[i]);
+            }
+
+            //执行SQL语句
+            rst = pst.executeQuery();
+        } catch (SQLException e) {
+            System.out.println("执行查询异常");
+            e.printStackTrace();
+        }
+        return rst;
+    }
+
+    //增删改
+    public static int query01(String sql,String ...keys){
+        System.out.println("查询中...");
+        Connection conn = getConn();
+        int num=0;
+        try {
+            PreparedStatement pst = conn.prepareStatement(sql);
+            for (int i = 0; i < keys.length; i++) {
+                pst.setString((i+1),keys[i]);
+            }
+            num = pst.executeUpdate();
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+        return num;
+    }
+}
+
+~~~
+
+~~~ java
+// 查询测试类
+package Servlet;
+
+import util.DBUtli;
+
+import javax.jws.WebService;
+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.ResultSet;
+import java.sql.SQLException;
+
+@WebServlet("/mxdx")
+public class StudentServlet extends HttpServlet {
+
+    @Override
+    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        System.out.println("你收到一个请求...666");
+        resp.setContentType("text/html;charset=utf-8");
+        resp.setCharacterEncoding("utf-8");
+        PrintWriter out = resp.getWriter();
+        out.write("你收到一个请求。。。6666");
+        String sql ="select * from student";
+        ResultSet rst = DBUtli.query(sql);
+        out.write("<table border = 1>");
+        out.write("<tr><th>编号</th><th>姓名</th><th>性别</th></tr>");
+        try {
+            while (rst.next()){
+                int id = rst.getInt(1);
+                String name = rst.getString(2);
+                String sex = rst.getString(3);
+                out.write("<tr><td>"+id+"</td><td>"+name+"</td><td>"+sex+"</td></tr>");
+            }
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+        out.write("</table>");
+
+    }
+    @Override
+    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        super.doPost(req, resp);
+    }
+}
+
+~~~
+
+~~~ java
+// 修改测试类
+package Servlet;
+
+import util.DBUtli;
+
+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;
+
+@WebServlet("/up")
+public class StudentServlet01 extends HttpServlet {
+
+    @Override
+    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        resp.setContentType("text/html;charset=utf-8");
+        resp.setCharacterEncoding("utf-8");
+        PrintWriter out = resp.getWriter();
+        String sql ="update student set name='官文诚' where id=2";
+        out.write("<table border = 1>");
+        out.write("<tr><th>编号</th><th>姓名</th><th>性别</th></tr>");
+        out.write("</table>");
+        int query = DBUtli.query01(sql);
+        if (query>0){
+            out.write("修改成功");
+        }else {
+            out.write("修改失败");
+        }
+    }
+    @Override
+    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        super.doPost(req, resp);
+    }
+}
+
+~~~
+
-- 
Gitee