Servlet实现完整功能增删改查-完整代码

我自主完成的Servlet连接数据库实现完整功能增删改查的代码，放在这里，也可以到我github上下载：

练习项目-Servlet实现数据库增删改查-新闻发布系统 Exercise project -Servlet to achieve database additions, deletions, changes and checks - news release system

这个系统是纯用Servlet写的，是我用来练习的项目，没有用jsp，当然其实混合jsp制作更加方便，但我觉得jsp页面虽然好写，

但是这个小系统直接用servlet就够了，也比较简洁，而且毕竟jsp其实就是一种形式比较方便的servlet，本质上还是servlet，

目前实现的功能：

1.能够实现不同用户身份的登录，注册。

2.能够根据不同用户身份跳转到不同用户页面，分为普通用户，撰稿人，管理员。

3.能够实现防止非法登录。

4.管理员界面：能够修改用户账户信息，包括账户密码身份，删除用户账户信息。

5.撰稿人界面：能够实现发布稿件的功能，实现查看本人发布的新闻，修改或者删除本人发布的新闻。

6.用户界面：能够实现查看浏览新闻，有搜索框能实现模糊查询。

DB.java

package com;

import java.sql.*;

public class DB {
    public Connection conn = null;
    public Statement stmt = null;
    public ResultSet rs = null;
    String url = "jdbc:mysql://localhost:3306/test001?useSSL=false&serverTimezone=UTC";
    String username = "root";
    String password = "123";
    public DB(){
        try{
            Class.forName("com.mysql.cj.jdbc.Driver");
            conn = DriverManager.getConnection(url,username,password);
            stmt = conn.createStatement();
        }catch(SQLException se){
            // 处理 JDBC 错误
            se.printStackTrace();
        }catch(Exception e){
            // 处理 Class.forName 错误
            e.printStackTrace();
        }
    }
    public void close(){
        try {
            if (rs!=null){
                rs.close();
            }
            if (stmt!=null){
                stmt.close();
            }
            if (conn!=null){
                conn.close();
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }

}

DaoCrud.java

package Dao;

import com.DB;

import java.sql.PreparedStatement;
import java.sql.SQLException;

public class DaoCrud {
    public DaoCrud(){

    }
    public void AddNews(String title,String text,String writer,String date){
        DB db = new DB();
        PreparedStatement preparedStatement=null;
        try {
            String sql = "INSERT INTO news_info (news_title,news_text,news_writer,news_date) values (?,?,?,?)";
            preparedStatement=db.conn.prepareStatement(sql);
            preparedStatement.setString(1,title);
            preparedStatement.setString(2,text);
            preparedStatement.setString(3,writer);
            preparedStatement.setString(4,date);
            preparedStatement.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally{
        }
    }
    public void AddUser(String name,String pass,String ident){
        DB db = new DB();
        PreparedStatement preparedStatement=null;
        try {
            String sql = "INSERT INTO user_info (user_name,user_password,user_identity) values (?,?,?)";
            preparedStatement=db.conn.prepareStatement(sql);
            preparedStatement.setString(1,name);
            preparedStatement.setString(2,pass);
            preparedStatement.setString(3,ident);
            preparedStatement.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally{
        }
    }
    public void UpdateNews(String title,String text,String writer,String date,int id){
        DB db = new DB();
        PreparedStatement preparedStatement=null;
        try {
            String sql = "UPDATE news_info SET news_title=?, news_text=?, news_writer=?, news_date=? WHERE news_id=?";
            preparedStatement=db.conn.prepareStatement(sql);
            preparedStatement.setString(1,title);
            preparedStatement.setString(2,text);
            preparedStatement.setString(3,writer);
            preparedStatement.setString(4,date);
            preparedStatement.setInt(5,id);
            preparedStatement.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally{

        }
    }
    public void UpdateName(String name,String pass,String ident,int id){
        DB db = new DB();
        PreparedStatement preparedStatement=null;
        try {
            String sql = "UPDATE user_info SET user_name=?, user_password=?, user_identity=? WHERE user_id=?";
            preparedStatement=db.conn.prepareStatement(sql);
            preparedStatement.setString(1,name);
            preparedStatement.setString(2,pass);
            preparedStatement.setString(3,ident);
            preparedStatement.setInt(4,id);
            preparedStatement.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally{

        }
    }
    public void DeleteNews(int id){
        DB db = new DB();
        PreparedStatement preparedStatement=null;
        try {
            String sql = "DELETE FROM news_info WHERE news_id=?";
            preparedStatement=db.conn.prepareStatement(sql);
            preparedStatement.setInt(1,id);
            preparedStatement.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally{
        }
    }
    public void DeleteName(int id){
        DB db = new DB();
        PreparedStatement preparedStatement=null;
        try {
            String sql = "DELETE FROM user_info WHERE user_id=?";
            preparedStatement=db.conn.prepareStatement(sql);
            preparedStatement.setInt(1,id);
            preparedStatement.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally{
        }
    }

}

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("/Login")
public class Login extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        try {
            PrintWriter out = resp.getWriter();

            String title1 = "登录";
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + title1 + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + title1 + "</h1>\n" +
                    "<form action=\"LoginJudge\" method=\"POST\">" +
                    "账号：<input type=\"text\" name=\"put_name\"><br>"+
                    "密码：<input type=\"password\" name=\"put_password\"><br>" +
                    "登录身份：<input type=\"radio\" name=\"put_identity\" value=\"普通用户\">普通用户"+
                    "<input type=\"radio\" name=\"put_identity\" value=\"撰稿人\">撰稿人"+
                    "<input type=\"radio\" name=\"put_identity\" value=\"管理员\">管理员"+
                    "<br>"+
                    "<input type=\"submit\" value=\"登录\">" +
                    "</form>" +
                    "<form action=\"Register\" method=\"POST\">" +
                    "<input type=\"submit\" value=\"注册\">"+
                    "</form>"+
                    "<body><html>"
            );
        }catch (Exception e){
            e.printStackTrace();
        }

    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    @Override
    public void destroy() {

    }
}

import com.DB;

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;

@WebServlet("/LoginJudge")
public class LoginJudge extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        DB db = new DB();
        try {
            PrintWriter out = resp.getWriter();

            String na =new String(req.getParameter("put_name").getBytes("ISO8859-1"),"UTF-8");
            String pw = new String(req.getParameter("put_password").getBytes("ISO8859-1"),"UTF-8");
            String iy = new String(req.getParameter("put_identity").getBytes("ISO8859-1"),"UTF-8");
            //获得session空间
            HttpSession hs = req.getSession(true);
            //修改session的存在时间为200秒
            hs.setMaxInactiveInterval(200);

            db.rs = db.stmt.executeQuery("SELECT * FROM user_info WHERE user_name="+"'"+na+"'");

            if (db.rs.next()){

                if (pw.equals(db.rs.getString("user_password"))){

                    if (iy.equals(db.rs.getString("user_identity"))){

                        switch (iy){
                            case "普通用户":
                                //设置session 名为u_pass 值为ok
                                hs.setAttribute("u_pass","ok");
                                hs.setAttribute("u_name",na);
                                String site1 = new String("http://localhost:8080/MyCRUD_war_exploded/User1");
                                resp.setStatus(resp.SC_MOVED_TEMPORARILY);
                                resp.setHeader("Location", site1);
                                break;
                            case "撰稿人":
                                hs.setAttribute("w_pass","ok");
                                hs.setAttribute("w_name",na);
                                String site2 = new String("http://localhost:8080/MyCRUD_war_exploded/Writer1");
                                resp.setStatus(resp.SC_MOVED_TEMPORARILY);
                                resp.setHeader("Location", site2);
                                break;
                            case "管理员":
                                hs.setAttribute("a_pass","ok");
                                hs.setAttribute("a_name",na);
                                String site3 = new String("http://localhost:8080/MyCRUD_war_exploded/Admin1");
                                resp.setStatus(resp.SC_MOVED_TEMPORARILY);
                                resp.setHeader("Location", site3);
                                break;
                        }

                    } else{
                        out.print("<script language='javaScript'> alert('登陆身份错误');</script>");
                        resp.setHeader("refresh", "0;url=Login");
                    }

                } else{
                    out.print("<script language='javaScript'> alert('密码错误');</script>");
                    resp.setHeader("refresh", "0;url=Login");
                }

            }else {
                out.print("<script language='javaScript'> alert('用户名错误');</script>");
                resp.setHeader("refresh", "0;url=Login");
            }
        }catch (Exception e){
            e.printStackTrace();
        } finally{
            db.close();
        }

    }
    @Override
    public void destroy() {

    }
}

import Dao.DaoCrud;
import com.DB;

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.*;


@WebServlet("/Register")
public class Register extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 设置响应内容类型
        resp.setContentType("text/html;charset=UTF-8");
        try {
            PrintWriter out = resp.getWriter();

            String title1 = "注册";
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + title1 + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + title1 + "</h1>\n" +
                    "<form action=\"RegJudge\" method=\"POST\">" +
                    "账号：<input type=\"text\" name=\"reg_name\"><br>"+
                    "密码：<input type=\"password\" name=\"reg_password\"><br>" +
                    "登录身份：<input type=\"radio\" name=\"reg_identity\" value=\"普通用户\">普通用户"+
                    "<input type=\"radio\" name=\"reg_identity\" value=\"撰稿人\">撰稿人"+
                    "<br>"+
                    "<input type=\"submit\" value=\"注册\">" +
                    "</form>" +
                    "<br><input type=\"button\" value=\"点击返回\" onclick=\"location.href='Login'\" />"+
                    "<body><html>"
            );
        }catch (Exception e){
            e.printStackTrace();
        }
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }

    @Override
    public void destroy() {

    }
}

import Dao.DaoCrud;
import com.DB;

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("/RegJudge")
public class RegJudge extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // 设置响应内容类型
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();

        String name =new String(request.getParameter("reg_name").getBytes("ISO8859-1"),"UTF-8");
        String password = new String(request.getParameter("reg_password").getBytes("ISO8859-1"),"UTF-8");
        String identity = new String(request.getParameter("reg_identity").getBytes("ISO8859-1"),"UTF-8");

        try {
            DB db = new DB();
            DaoCrud crud = new DaoCrud();

            if(identity==""||password==""||name==""){
                out.println("<!DOCTYPE html> \n" +
                        "<html>\n" +
                        "<head><title>" + "提交失败" + "</title></head>\n" +
                        "<body bgcolor=\"#f0f0f0\">\n" +
                        "<h1 align=\"center\">" + "提交失败，标题或内容不能为空" + "</h1>\n" +
                        "<input type=\"button\" value=\"点击返回\" onclick=\"location.href='Register'\" />"+
                        "</body></html>"
                );
            }else {
                crud.AddUser(name,password,identity);
                out.println("<!DOCTYPE html> \n" +
                        "<html>\n" +
                        "<head><title>" + "注册成功" + "</title></head>\n" +
                        "<body bgcolor=\"#f0f0f0\">\n" +
                        "<h1 align=\"center\">" + "注册成功" + "</h1>\n" +
                        "<input type=\"button\" value=\"点击返回登录\" onclick=\"location.href='Login'\" />"+
                        "</body></html>"
                );
            }
        }catch (Exception e){
            e.printStackTrace();
        }

    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }

    @Override
    public void destroy() {

    }
}

import Dao.DaoCrud;
import com.DB;

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;
import java.text.SimpleDateFormat;
import java.util.Date;

@WebServlet("/Search1")
public class Search1 extends HttpServlet {
    @Override
    public void init() throws ServletException {

    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        //获取session
        HttpSession hs = req.getSession(true);
        String na = (String) hs.getAttribute("u_name");
        String value = (String) hs.getAttribute("pass");
        //获取日期
        java.util.Date dat = new Date();
        SimpleDateFormat ft = new SimpleDateFormat("yyyy.MM.dd");
        String putin = new String(req.getParameter("put_in").getBytes("ISO8859-1"),"UTF-8");
        //数据库连接
        DB db = new DB();
        try {
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + "搜索界面" + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + "搜索结果" + "</h1>\n" +
                    "<br><input type=\"button\" value=\"点击返回主菜单\" onclick=\"location.href='User1'\" />"
            );
            db.rs = db.stmt.executeQuery("SELECT * FROM news_info WHERE news_title LIKE " + "'%" + putin + "%'");
            while (db.rs.next()) {
                out.println("<br>");
                String title = db.rs.getString("news_title");
                String text = db.rs.getString("news_text");
                String writer = db.rs.getString("news_writer");
                String date = db.rs.getString("news_date");
                int id = db.rs.getInt("news_id");
                out.println(title);
                out.println("<br>");
                out.println(text);
                out.println("<br>");
                out.print("作者" + writer);
                out.print("日期: " + date);
                out.println("<br>");
            }
            out.println("</body></html>");
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            db.close();
        }
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }
    @Override
    public void destroy() {
    }
}

import com.DB;

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 javax.servlet.http.HttpSession;
import javax.xml.transform.Result;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.sql.*;

@WebServlet("/User1")
public class User1 extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        //得到session
        HttpSession hs = req.getSession(true);
        String na = (String) hs.getAttribute("u_name");
        String value = (String) hs.getAttribute("u_pass");
        // 获取日期格式 yyyy.MM.dd  hh:mm:ss E a
        Date dat = new Date();
        SimpleDateFormat ft =
                new SimpleDateFormat("yyyy.MM.dd");
        //连接数据库，创建数据库对象
        DB db = new DB();
        //判断
        if (value!="ok"){
            try {
                //非法登录
                resp.sendRedirect("Login");
            }catch (Exception e){
                e.printStackTrace();
            }
        }
        try {
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + "用户界面" + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + "用户界面：浏览新闻" + "</h1>\n" +
                    "<h3 align=\"center\">" + "成功登录，你的用户名是 " + na + "</h3>\n" +
                    "<h3 align=\"center\">" + "现在的日期 " + ft.format(dat) + "</h3>\n"+
                    "<br><input type=\"button\" value=\"点击返回\" onclick=\"location.href='Login'\" />"+
                    "<form action=\"Search1\" method=\"POST\">" +
                    "<input type=\"text\" name=\"put_in\">"+
                    "<input type=\"submit\" value=\"搜索\">"+
                    "</form>"
            );
            db.rs = db.stmt.executeQuery("SELECT news_title,news_text,news_writer,news_date FROM news_info");
            while (db.rs.next()) {
                out.println("<br>");
                String title = db.rs.getString("news_title");
                String text = db.rs.getString("news_text");
                String writer = db.rs.getString("news_writer");
                String date = db.rs.getString("news_date");

                out.println(title);
                out.println("<br>");
                out.println(text);
                out.println("<br>");
                out.println("作者" + writer);
                out.println("日期: " + date);
                out.println("<br>");
                out.println("<br>");
            }
                out.println("</body></html>");
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            db.close();
        }


    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    @Override
    public void destroy() {

    }
}

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.sql.*;

@WebServlet("/Writer1")
public class Writer1 extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();

        HttpSession hs = req.getSession(true);
        //获取姓名
        String na = (String) hs.getAttribute("w_name");
        String value = (String) hs.getAttribute("w_pass");
        //获取日期
        Date dat = new Date();
        SimpleDateFormat ft =
                new SimpleDateFormat("yyyy.MM.dd");
        out.println("<!DOCTYPE html> \n" +
                "<html>\n" +
                "<head><title>" + "撰稿界面" + "</title></head>\n" +
                "<body bgcolor=\"#f0f0f0\">\n" +
                "<h1 align=\"center\">" + "发布你的稿件" + "</h1>\n" +
                "<h3 align=\"center\">" + "撰稿人成功登录，你的用户名是 " + na + "</h3>\n"+
                "<h3 align=\"center\">" + "现在的日期 " + ft.format(dat) + "</h3>\n"+
                "<br><input type=\"button\" value=\"点击返回\" onclick=\"location.href='Login'\" />"+
                "<form action=\"Writer2\" method=\"POST\">"+
                "<h3>新闻标题</h3><br>"+
                "<input type=\"text\" name=\"publish_title\" size=\"65\"><br>"+
                "<h3>新闻内容</h3>"+
                "<textarea rows=\"15\" cols=\"60\"  name=\"publish_text\">"+
                "</textarea>"+
                "<h4>作者</h4>"+ na +
                "<input type=\"hidden\" name=\"publish_writer\" value="+ na +"><br>"+
                "<h4>日期</h4>"+ ft.format(dat) +
                "<input type=\"hidden\" name=\"publish_date\" value=" + ft.format(dat) + "><br>" +
                "<input type=\"submit\" value=\"发布我的稿件\">"+
                "</form>"+
                "<form id=\"form1\" name=\"form1\" method=\"POST\" action=\"Writer3\">" +
                "<input type=\"submit\" value=\"查看并修改稿件\">"+
                "</form>"+
                "</body></html>"
        );
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }
    @Override
    public void destroy() {

    }
}

import Dao.DaoCrud;
import com.DB;

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;

@WebServlet("/Writer2")
public class Writer2 extends HttpServlet {
    @Override
    public void init() throws ServletException {

    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        //获取session
        HttpSession hs = req.getSession(true);
        String na = (String) hs.getAttribute("w_name");
        String value = (String) hs.getAttribute("w_pass");
        DB db = new DB();
        //获取表单信息
        String title_check =req.getParameter("publish_title");
        String text_check =req.getParameter("publish_text");
        String title = new String(req.getParameter("publish_title").getBytes("ISO8859-1"),"UTF-8");
        String text = new String(req.getParameter("publish_text").getBytes("ISO8859-1"),"UTF-8");
        String writer = new String(req.getParameter("publish_writer").getBytes("ISO8859-1"),"UTF-8");
        String date =new String(req.getParameter("publish_date").getBytes("ISO8859-1"),"UTF-8");
        DaoCrud crud = new DaoCrud();
        //检测内容是否为空
        if(title_check==""||text_check==""){
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + "提交失败" + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + "提交失败，标题或内容不能为空" + "</h1>\n" +
                    "<input type=\"button\" value=\"点击返回\" onclick=\"location.href='Writer1'\" />"+
                    "</body></html>"
            );
        }else {
            crud.AddNews(title,text,writer,date);
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + "发布成功" + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + "发布成功" + "</h1>\n" +
                    "<input type=\"button\" value=\"点击返回\" onclick=\"location.href='Writer1'\" />"+
                    "</body></html>"
            );
        }

    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }
    @Override
    public void destroy() {
    }
}

import Dao.DaoCrud;
import com.DB;

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;
import java.text.SimpleDateFormat;
import java.util.Date;

@WebServlet("/Writer3")
public class Writer3 extends HttpServlet {
    @Override
    public void init() throws ServletException {

    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        //获取session
        HttpSession hs = req.getSession(true);
        String na = (String) hs.getAttribute("w_name");
        String value = (String) hs.getAttribute("w_pass");
        //获取日期
        java.util.Date dat = new Date();
        SimpleDateFormat ft = new SimpleDateFormat("yyyy.MM.dd");
        //数据库连接
        DB db = new DB();
        try {
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + "修改界面" + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + "修改界面" + "</h1>\n" +
                    "<h3 align=\"center\">" + "修改你的稿件"
            );
            out.println("<br><input type=\"button\" value=\"点击返回主菜单\" onclick=\"location.href='Writer1'\" />");
            db.rs = db.stmt.executeQuery("SELECT news_title,news_text,news_writer,news_date,news_id FROM news_info WHERE news_writer="+"'"+na+"'");
            while (db.rs.next()) {
                out.println("<br>");
                String title = db.rs.getString("news_title");
                String text = db.rs.getString("news_text");
                String writer = db.rs.getString("news_writer");
                String date = db.rs.getString("news_date");
                int id = db.rs.getInt("news_id");
                out.println(title);
                out.println("<br>");
                out.println(text);
                out.println("<br>");
                out.print("作者" + writer);
                out.print("日期: " + date);
                out.println("<form action=\"Writer4\" method=\"POST\">"+
                            "<input type=\"hidden\" name=\"old_title\" value="+ title +">"+
                            "<input type=\"hidden\" name=\"old_text\" value="+ text +">"+
                            "<input type=\"hidden\" name=\"old_id\" value="+ id +"><br>"+
                            "<input type=\"submit\" value=\"修改此稿件\">"+
                            "</form>"+
                            "<form id=\"form2\" name=\"form2\" method=\"POST\" action=\"Delete1\">" +
                            "<input type=\"hidden\" name=\"delete_id\" value="+ id +">"+
                            "<input type=\"submit\" value=\"删除此稿件\">"+
                            "</form>"
                );
                out.println("<br>");
            }
            out.println("</body></html>");
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            db.close();
        }
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }
    @Override
    public void destroy() {
    }
}

import Dao.DaoCrud;
import com.DB;

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;
import java.text.SimpleDateFormat;
import java.util.Date;

@WebServlet("/Writer4")
public class Writer4 extends HttpServlet {
    @Override
    public void init() throws ServletException {

    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        //获取session
        HttpSession hs = req.getSession(true);
        String na = (String) hs.getAttribute("w_name");
        String value = (String) hs.getAttribute("w_pass");
        //获取日期
        java.util.Date dat = new Date();
        SimpleDateFormat ft = new SimpleDateFormat("yyyy.MM.dd");
        //数据库连接
        DB db = new DB();
        //获取旧的文本
        String title = new String(req.getParameter("old_title").getBytes("ISO8859-1"),"UTF-8");
        String text = new String(req.getParameter("old_text").getBytes("ISO8859-1"),"UTF-8");
        int id = Integer.parseInt(req.getParameter("old_id"));
        out.println("<!DOCTYPE html> \n" +
                "<html>\n" +
                "<head><title>" + "修改界面" + "</title></head>\n" +
                "<body bgcolor=\"#f0f0f0\">\n" +
                "<h1 align=\"center\">" + "修改你的稿件" + "</h1>\n" +
                "<br><input type=\"button\" value=\"点击返回\" onclick=\"location.href='Writer1'\" />"+
                "<form action=\"Writer5\" method=\"POST\">"+
                "<h3>新闻标题</h3><br>"+
                "<input type=\"text\" name=\"modify_title\" value="+ title +"><br>"+
                "<h3>新闻内容</h3>"+
                "<textarea rows=\"15\" cols=\"60\"  name=\"modify_text\" value=>"+
                text +
                "</textarea>"+
                "<h4>作者</h4>"+ na +
                "<input type=\"hidden\" name=\"modify_writer\" value="+ na +">"+
                "<h4>日期</h4>"+ ft.format(dat) +
                "<input type=\"hidden\" name=\"modify_date\" value=" + ft.format(dat) + ">" +
                "<input type=\"hidden\" name=\"modify_id\" value="+ id +">"+
                "<input type=\"submit\" value=\"修改\">"+
                "</form>"  +
                "</body></html>"
        );
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }
    @Override
    public void destroy() {
    }
}

import Dao.DaoCrud;
import com.DB;

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;

@WebServlet("/Writer5")
public class Writer5 extends HttpServlet {
    @Override
    public void init() throws ServletException {

    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        //获取session
        HttpSession hs = req.getSession(true);
        String na = (String) hs.getAttribute("w_name");
        String value = (String) hs.getAttribute("w_pass");
        DB db = new DB();
        //获取表单信息
        String title_check =req.getParameter("modify_title");
        String text_check =req.getParameter("modify_text");
        String title = new String(req.getParameter("modify_title").getBytes("ISO8859-1"),"UTF-8");
        String text = new String(req.getParameter("modify_text").getBytes("ISO8859-1"),"UTF-8");
        String writer = new String(req.getParameter("modify_writer").getBytes("ISO8859-1"),"UTF-8");
        String date = new String(req.getParameter("modify_date").getBytes("ISO8859-1"),"UTF-8");
        int id  = Integer.parseInt(req.getParameter("modify_id"));
        DaoCrud crud = new DaoCrud();
        //检测内容是否为空
        if(title_check==""||text_check==""){
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + "提交失败" + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + "修改失败，标题或内容不能为空" + "</h1>\n" +
                    "<input type=\"button\" value=\"点击返回\" onclick=\"location.href='Writer1'\" />"+
                    "</body></html>"
            );
        }else {
            crud.UpdateNews(title,text,writer,date,id);
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + "修改成功" + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + "修改成功" + "</h1>\n" +
                    "<input type=\"button\" value=\"点击返回\" onclick=\"location.href='Writer1'\" />"+
                    "</body></html>"
            );
        }

    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }
    @Override
    public void destroy() {
    }
}

import com.DB;

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.sql.*;

@WebServlet("/Admin1")
public class Admin1 extends HttpServlet {
    @Override
    public void init() throws ServletException {

    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        //得到session
        HttpSession hs = req.getSession(true);
        String na = (String) hs.getAttribute("a_name");
        String value = (String) hs.getAttribute("pass");
        // 获取日期格式 yyyy.MM.dd  hh:mm:ss E a
        Date dat = new Date();
        SimpleDateFormat ft =
                new SimpleDateFormat("yyyy.MM.dd");
        //连接数据库，创建数据库对象
        DB db = new DB();
        //判断
        try {
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + "管理员界面" + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + "管理员界面" + "</h1>\n" +
                    "<h3 align=\"center\">" + "管理员，你好 " + na + "</h3>\n" +
                    "<h3 align=\"center\">" + "现在的日期 " + ft.format(dat) + "</h3>\n"+
                    "<br><input type=\"button\" value=\"点击返回登录页面\" onclick=\"location.href='Login'\" />"+
                    "<form action=\"Admin2\" method=\"POST\">" +
                    "<input type=\"submit\" value=\"管理用户信息\">"+
                    "</form>"
            );
            out.println("</body></html>");
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            db.close();
        }


    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    @Override
    public void destroy() {

    }
}

import com.DB;

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 javax.servlet.http.HttpSession;
import javax.xml.transform.Result;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.sql.*;

@WebServlet("/Admin2")
public class Admin2 extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        //得到session
        HttpSession hs = req.getSession(true);
        String na = (String) hs.getAttribute("a_name");
        String value = (String) hs.getAttribute("pass");
        // 获取日期格式 yyyy.MM.dd  hh:mm:ss E a
        Date dat = new Date();
        SimpleDateFormat ft =
                new SimpleDateFormat("yyyy.MM.dd");
        //连接数据库，创建数据库对象
        DB db = new DB();
        //判断
//        if (value==null){
//            try {
//                //非法登录
//                resp.sendRedirect("Login");
//            }catch (Exception e){
//                e.printStackTrace();
//            }
//        }
        try {
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + "管理员界面" + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + "管理员界面" + "</h1>\n" +
                    "<h3 align=\"center\">" + "管理员用户信息 " + na + "</h3>\n" +
                    "<br><input type=\"button\" value=\"点击返回\" onclick=\"location.href='Admin1'\" />"
            );
            db.rs = db.stmt.executeQuery("SELECT user_name, user_password, user_identity, user_id FROM user_info");
            while (db.rs.next()) {
                out.println("<br>");

                String name = db.rs.getString("user_name");
                String password = db.rs.getString("user_password");
                String identity = db.rs.getString("user_identity");
                int id  = db.rs.getInt("user_id");
                out.println("<br>");
                out.println("账号:" + name);
                out.println("密码:" + password);
                out.println("身份:" + identity);
                out.println("<br>");
                out.println("<form action=\"Admin3\" method=\"POST\">"+
                        "<input type=\"hidden\" name=\"old_name\" value="+ name +">"+
                        "<input type=\"hidden\" name=\"old_password\" value="+ password +">"+
                        "<input type=\"hidden\" name=\"old_identity\" value="+ identity +">"+
                        "<input type=\"hidden\" name=\"old_id\" value="+ id +">"+
                        "<input type=\"submit\" value=\"修改此账户\">"+
                        "</form>"+
                        "<form method=\"POST\" action=\"Admin4\">" +
                        "<input type=\"hidden\" name=\"delete_name\" value="+ name +">"+
                        "<input type=\"hidden\" name=\"delete_id\" value="+ id +">"+
                        "<input type=\"submit\" value=\"删除此账户\">"+
                        "</form>"
                );
            }
            out.println("</body></html>");
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            db.close();
        }


    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    @Override
    public void destroy() {

    }
}

import Dao.DaoCrud;
import com.DB;

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;
import java.text.SimpleDateFormat;
import java.util.Date;

@WebServlet("/Admin3")
public class Admin3 extends HttpServlet {
    @Override
    public void init() throws ServletException {

    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        //获取session
        HttpSession hs = req.getSession(true);
        String na = (String) hs.getAttribute("a_name");
        String value = (String) hs.getAttribute("pass");
        //数据库连接
        DB db = new DB();
        //获取旧的文本
        String name = new String(req.getParameter("old_name").getBytes("ISO8859-1"),"UTF-8");
        String password = new String(req.getParameter("old_password").getBytes("ISO8859-1"),"UTF-8");
        String identity = new String(req.getParameter("old_identity").getBytes("ISO8859-1"),"UTF-8");
        int id = Integer.parseInt(req.getParameter("old_id"));

        try {
            String title1 = "修改账户信息";
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + title1 + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h1 align=\"center\">" + title1 + "</h1>\n" +
                    "<br><input type=\"button\" value=\"点击返回\" onclick=\"location.href='Admin2'\" />"+
                    "<form action=\"AdminModify\" method=\"POST\">" +
                    "账号：<input type=\"text\" name=\"mod_name\" value="+ name +"><br>"+
                    "密码：<input type=\"text\" name=\"mod_password\" value="+ password +"><br>"
            );
            switch (identity){

                case "普通用户":
                    out.println(
                            "登录身份：<input type=\"radio\" name=\"mod_identity\" value=\"普通用户\" checked=\"checked\">普通用户"+
                                    "<input type=\"radio\" name=\"mod_identity\" value=\"撰稿人\">撰稿人"+
                                    "<input type=\"radio\" name=\"mod_identity\" value=\"管理员\">管理员"
                    );
                    break;
                case "撰稿人":
                    out.println(
                            "登录身份：<input type=\"radio\" name=\"mod_identity\" value=\"普通用户\">普通用户"+
                                    "<input type=\"radio\" name=\"mod_identity\" value=\"撰稿人\" checked=\"checked\">撰稿人"+
                                    "<input type=\"radio\" name=\"mod_identity\" value=\"管理员\">管理员"
                    );
                    break;
                case "管理员":
                    out.println(
                            "登录身份：<input type=\"radio\" name=\"mod_identity\" value=\"普通用户\">普通用户"+
                                    "<input type=\"radio\" name=\"mod_identity\" value=\"撰稿人\">撰稿人"+
                                    "<input type=\"radio\" name=\"mod_identity\" value=\"管理员\" checked=\"checked\">管理员"
                    );
                    break;

            }
            out.println(
                            "<br>"+
                            "<input type=\"hidden\" name=\"mod_id\" value="+ id +">"+
                            "<input type=\"submit\" value=\"修改\">" +
                            "</form>" +
                            "<body><html>"
            );
        }catch (Exception e){
            e.printStackTrace();
        }

    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }
    @Override
    public void destroy() {

    }
}

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("/Admin4")
public class Admin4 extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        try {
            PrintWriter out = resp.getWriter();
            int id = Integer.parseInt(req.getParameter("delete_id"));
            String title1 = "你确认删除此账号么，删除后不可撤销";
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + title1 + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h2 align=\"center\">" + title1 + "</h2>\n" +
                    "<form action=\"AdminDelete1\" method=\"POST\">" +
                    "<input type=\"hidden\" name=\"delete_id_0\" value="+ id +">"+
                    "<input type=\"submit\" value=\"确认删除\">" +
                    "</form>" +
                    "<br><input type=\"button\" value=\"点击取消\" onclick=\"location.href='Admin3'\" />"+
                    "<body><html>"
            );
        }catch (Exception e){
            e.printStackTrace();
        }

    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    @Override
    public void destroy() {

    }
}

import Dao.DaoCrud;
import com.DB;

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("/AdminDelete1")
public class AdminDelete1 extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        DB db = new DB();

        try {
            String id = req.getParameter("delete_id_0");
            DaoCrud crud = new DaoCrud();
            crud.DeleteName(Integer.parseInt(id));
            String title1 = "删除成功！";
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + title1 + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h2 align=\"center\">" + title1 + "</h2>\n" +
                    "<form action=\"Admin2\" method=\"POST\">" +
                    "<input type=\"submit\" value=\"点击返回\">" +
                    "</form>" +
                    "<body><html>"
            );
        }catch (Exception e){
            e.printStackTrace();
        }

    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    @Override
    public void destroy() {

    }
}

import Dao.DaoCrud;
import com.DB;

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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;

@WebServlet("/AdminModify")
public class AdminModify extends HttpServlet {
    @Override
    public void init() throws ServletException {

    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        //获取session
//        HttpSession hs = req.getSession(true);
//        String na = (String) hs.getAttribute("a_name");
//        String value = (String) hs.getAttribute("pass");
//        DB db = new DB();
        //获取表单信息
        String name_check =req.getParameter("mod_name");
        String password_check =req.getParameter("mod_password");
        String identity_check =req.getParameter("mod_identity");

        String name = new String(req.getParameter("mod_name").getBytes("ISO8859-1"),"UTF-8");
        String password = new String(req.getParameter("mod_password").getBytes("ISO8859-1"),"UTF-8");
        String identity = new String(req.getParameter("mod_identity").getBytes("ISO8859-1"),"UTF-8");
        int id = Integer.parseInt(req.getParameter("mod_id"));

        try {
            //检测内容是否为空
            if(name_check==""||password_check==""||identity_check==""){
                out.println("<!DOCTYPE html> \n" +
                        "<html>\n" +
                        "<head><title>" + "失败" + "</title></head>\n" +
                        "<body bgcolor=\"#f0f0f0\">\n" +
                        "<h1 align=\"center\">" + "修改失败，不能为空" + "</h1>\n" +
                        "<input type=\"button\" value=\"点击返回\" onclick=\"location.href='Admin2'\" />"
                );
            }else {
                DaoCrud crud = new DaoCrud();
                crud.UpdateName(name,password,identity,id);
                out.println("<!DOCTYPE html> \n" +
                        "<html>\n" +
                        "<head><title>" + "修改成功" + "</title></head>\n" +
                        "<body bgcolor=\"#f0f0f0\">\n" +
                        "<h1 align=\"center\">" + "修改成功" + "</h1>\n" +
                        "<input type=\"button\" value=\"点击返回\" onclick=\"location.href='Admin2'\" />"
                );
            }
            out.println("</body></html>");
        }catch (Exception e){
            e.printStackTrace();
        }

    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }
    @Override
    public void destroy() {
    }
}

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("/Delete1")
public class Delete1 extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        try {
            PrintWriter out = resp.getWriter();
            int id = Integer.parseInt(req.getParameter("delete_id"));
            String title1 = "你确认删除此新闻么，删除后不可撤销";
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + title1 + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h2 align=\"center\">" + title1 + "</h2>\n" +
                    "<form action=\"Delete2\" method=\"POST\">" +
                    "<input type=\"hidden\" name=\"delete_id_0\" value="+ id +">"+
                    "<input type=\"submit\" value=\"确认删除\">" +
                    "</form>" +
                    "<br><input type=\"button\" value=\"点击取消\" onclick=\"location.href='Writer3'\" />"+
                    "<body><html>"
            );
        }catch (Exception e){
            e.printStackTrace();
        }

    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    @Override
    public void destroy() {

    }
}

import Dao.DaoCrud;
import com.DB;

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("/Delete2")
public class Delete2 extends HttpServlet {
    @Override
    public void init() throws ServletException {
    }
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter out = resp.getWriter();
        DB db = new DB();

        try {
            int id = Integer.parseInt(req.getParameter("delete_id_0"));
            DaoCrud crud = new DaoCrud();
            crud.DeleteNews(id);
            String title1 = "删除成功！";
            out.println("<!DOCTYPE html> \n" +
                    "<html>\n" +
                    "<head><title>" + title1 + "</title></head>\n" +
                    "<body bgcolor=\"#f0f0f0\">\n" +
                    "<h2 align=\"center\">" + title1 + "</h2>\n" +
                    "<form action=\"Writer3\" method=\"POST\">" +
                    "<input type=\"submit\" value=\"点击返回\">" +
                    "</form>" +
                    "<body><html>"
            );
        }catch (Exception e){
            e.printStackTrace();
        }

    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
    @Override
    public void destroy() {

    }
}

posted @ 2023-03-01 21:45 冰稀饭Aurora 阅读(144) 评论(0) 编辑收藏举报

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