From 69a1251c7783665518c2885d207ca046af9ca876 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E2=80=9C=E5=BE=90=E7=AB=8B=E5=9F=8E=E2=80=9D?=
<“897185960@qq.com”>
Date: Fri, 26 May 2023 23:53:31 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BD=9C=E4=B8=9A?=
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Content-Type: text/plain; charset=UTF-8
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---
.../import javax.md" | 154 ++++++++++++++++++
1 file changed, 154 insertions(+)
create mode 100644 "11 \345\276\220\347\253\213\345\237\216/import javax.md"
diff --git "a/11 \345\276\220\347\253\213\345\237\216/import javax.md" "b/11 \345\276\220\347\253\213\345\237\216/import javax.md"
new file mode 100644
index 0000000..1fa6c5a
--- /dev/null
+++ "b/11 \345\276\220\347\253\213\345\237\216/import javax.md"
@@ -0,0 +1,154 @@
+```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("/Servlet")
+public class Servlet extends HttpServlet {
+
+ @Override
+ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+ String sql="SELECT * FROM student; ";
+ response.setContentType("text/html;charset=utf-8");
+
+ try {
+ ResultSet rs = DBUtil.select(sql);
+ while (rs.next()){
+ int id =rs.getInt("id");
+ String name= rs.getString("name");
+ String sex= rs.getString("sex");
+ System.out.println(id+name+sex);
+ response.getWriter().write(id+name+sex);
+ }
+ } catch (Exception e) {
+ e.printStackTrace();
+ }
+ }
+
+ @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");
+
+
+ System.out.println("id="+id);
+ System.out.println("name="+name);
+ System.out.println("sex="+sex);
+ 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("成功");
+ }else {
+ response.getWriter().write("失败");
+ }
+ } catch (SQLException e) {
+ e.printStackTrace();
+ }
+ }
+
+ @Override
+ protected void doHead(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+ req.setCharacterEncoding("utf-8");
+ resp.setContentType("text/html;charset=utf-8");
+ String sql="SELECT * FROM student WHERE id=?";
+ try {
+ String id =req.getParameter("id");
+ int rs = DBUtil.Update(sql,id);
+ if(rs>0){
+ resp.getWriter().write("成功");
+ }else {
+ resp.getWriter().write("失败");
+ }
+ } catch (SQLException e) {
+ e.printStackTrace();
+ }
+ }
+
+}
+
+```
+
+```java
+
+import java.sql.*;
+import java.sql.SQLException;
+
+public class DBUtil {
+ private final static String url ="jdbc:mysql://localhost:3306/student_db?useSSL=false&useUnicode=true&characterEncoding=utf8";
+ private final static String name = "root";
+ private final static String password = "root";
+ static {
+ try{
+ Class.forName("com.mysql.jdbc.Driver");
+ }
+ catch (ClassNotFoundException e){
+ e.printStackTrace();
+ }
+ }
+ public static Connection getCon() throws SQLException{
+ Connection conn = DriverManager.getConnection(url,name,password);
+ return conn;
+
+ }
+ public static ResultSet select(String sql,String ...key) throws SQLException{
+ Connection conn =getCon();
+ PreparedStatement state = conn.prepareStatement(sql);
+ for (int i = 0; i < key.length; i++) {
+ state.setString(i,key[i]);
+ }
+ ResultSet res = state.executeQuery();
+ return res;
+ }
+ public static int Update(String url,String ...key) throws SQLException{
+ Connection conn = getCon();
+ PreparedStatement state = conn.prepareStatement(url);
+ for (int i = 0; i < key.length; i++) {
+ state.setString(i+1,key[i]);
+ }
+ int res = state.executeUpdate();
+ return res;
+ }
+}
+
+```
+
+```html
+
+
+
+
+ 添加学生
+
+
+ 添加学生
+
+
+修改学生
+
+
+
+