From 01c3254880eace827549d95eaa01a5ccc874fa55 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E8=B0=A2=E9=93=96=E6=B5=A9?= <1136734375@qq.com> Date: Thu, 25 May 2023 11:49:48 +0800 Subject: [PATCH] =?UTF-8?q?=E4=BD=9C=E4=B8=9A?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- .../20230525 Tomcat.md" | 230 ++++++++++++++++++ 1 file changed, 230 insertions(+) create mode 100644 "05 \350\260\242\351\223\226\346\265\251/20230525 Tomcat.md" diff --git "a/05 \350\260\242\351\223\226\346\265\251/20230525 Tomcat.md" "b/05 \350\260\242\351\223\226\346\265\251/20230525 Tomcat.md" new file mode 100644 index 0000000..8777989 --- /dev/null +++ "b/05 \350\260\242\351\223\226\346\265\251/20230525 Tomcat.md" @@ -0,0 +1,230 @@ +```java +// 方法类 +package servlet; + +import java.sql.*; + +public class FZ { + private static final String url = "jdbc:mysql:///student_db?useSSL=false&useUnicode=true&characterEncoding=utf8"; + private static final String user = "root"; + private static final 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(); + } + } + + public static Connection getConn() { + Connection conn = null; + try { + conn = DriverManager.getConnection(url, user, password); + } catch (SQLException e) { + System.out.println("获取连接对象失败"); + e.printStackTrace(); + } + return conn; + } + + public static ResultSet query(String sql, String... keys) { + ResultSet rs = null; + try { + Connection conn = getConn(); + PreparedStatement pst = conn.prepareStatement(sql); + for (int i = 0; i < keys.length; i++) { + pst.setString((i + 1), keys[i]); + } + rs = pst.executeQuery(); + } catch (SQLException e) { + System.out.println("执行查询异常"); + e.printStackTrace(); + } + return rs; + } +} + + + +// 添加类 + +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 StudentInsertServlet 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(); + Connection conn = FZ.getConn(); + try { + PreparedStatement pst = conn.prepareStatement("insert into student values (5,'NANA','N')"); + int i = pst.executeUpdate(); + if(i>0){ + out.write("添加成功"); + }else{ + out.write("添加失败"); + } + } catch (SQLException e) { + e.printStackTrace(); + } + } + + @Override + protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { + super.doPost(req, resp); + } +} + + + // 删除类 + +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 StudentDeleteServlet 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(); + Connection conn = FZ.getConn(); + try { + PreparedStatement pst = conn.prepareStatement("delete from student where id=4"); + int i = pst.executeUpdate(); + if(i>0){ + out.write("删除成功"); + }else { + out.write("删除失败"); + } + } catch (SQLException e) { + e.printStackTrace(); + } + } + + @Override + protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { + super.doPost(req, resp); + } +} + + +// 修改类 + + +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("/update") +public class StudentUpdateServlet 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(); + Connection conn = FZ.getConn(); + try { + PreparedStatement pst = conn.prepareStatement("update student set name='Know' where id=2"); + int i =pst.executeUpdate(); + if(i>0){ + out.write("修改成功"); + }else { + out.write("修改失败"); + } + } catch (SQLException e) { + e.printStackTrace(); + } + } + + @Override + protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { + super.doPost(req, resp); + } +} + + +// 查询类 + + +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.ResultSet; +import java.sql.SQLException; + +@WebServlet("/select") +public class StudentSelectServlet 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(); + ResultSet rst=FZ.query("select * from student"); + out.write(""); + out.write("" + + "" + + ""); + try { + while (rst.next()){ + int id = rst.getInt("id"); + String name = rst.getString("name"); + String sex = rst.getString("sex"); + out.write(""); + } + } catch (SQLException e) { + throw new RuntimeException(e); + } + out.write("
编号姓名性别
"+id+""+name+""+sex+"
"); + } + + @Override + protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { + super.doPost(req, resp); + } +} +``` \ No newline at end of file -- Gitee