package util;

import java.sql.*;

public class DBUtil {

    static String url = "jdbc:mysql://localhost:3306/class?useunicuee& characterEncoding=utf8";
static String username = "root";
static String password = "root";
static Connection conn = null;
static ResultSet rs = null;
static PreparedStatement ps = null; public static void init() {
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection(url,username,password);
}catch(Exception e) {
System.out.println("init [SQL驱动程序初始化失败!]");
e.printStackTrace();
}
} public static int addUpdDel(String sql) {
int i = 0;
try {
PreparedStatement ps = conn.prepareStatement(sql);
i = ps.executeUpdate();
}catch(SQLException e) {
System.out.println("sql数据库增删改异常!");
e.printStackTrace();
}
return i;
} public static ResultSet selectSql(String sql) {
try {
ps = conn.prepareStatement(sql);
rs = ps.executeQuery(sql);
}catch(SQLException e) {
System.out.println("sql数据库查询异常!");
e.printStackTrace();
}
return rs;
} public static void closeConn() {
try {
conn.close();
}catch(SQLException e) {
System.out.println("sql数据库关闭异常!");
e.printStackTrace();
} } }
package dao;

import java.util.List;
import entity.User; public interface UserDao { public boolean login(String name,String pwd);//登录
public boolean register(User user);//注册
public List<User> getUserAll();//返回用户信息集合
public boolean delete(int id);//根据id删除用户
public boolean update(int id,String name,String pwd,String sex,String home,String info);//更新用户信息 }
package dao;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List; import entity.User;
import util.DBUtil; public class UserDaoImpl implements UserDao{
public boolean register(User user) {
boolean flag = false;
DBUtil.init();
int i = DBUtil.addUpdDel("insert into user(name,pwd,sex,home,info)" +
"values('"+user.getName()+"','"+user.getPwd()+"','"+user.getSex()+"','"+user.getHome()+"','"+user.getInfo()+"')");
if(i>0) {
flag = true;
}
DBUtil.closeConn();
return flag;
} public boolean login(String name,String pwd) {
boolean flag = false;
try {
DBUtil.init();
ResultSet rs = DBUtil.selectSql("select * from user where name ='"+name+"' and pwd='"+pwd+"'");
while(rs.next()) {
if(rs.getString("name").equals(name)&&rs.getString("pwd").equals(pwd)) {
flag = true;
}
}
DBUtil.closeConn();
}catch(SQLException e) {
e.printStackTrace();
}
return flag;
} public List<User> getUserAll(){
List<User> list = new ArrayList<User>();
try {
DBUtil.init();
ResultSet rs = DBUtil.selectSql("select * from user");
while(rs.next()) {
User user = new User();
user.setId(rs.getInt("id"));
user.setName(rs.getString("name"));
user.setPwd(rs.getString("pwd"));
user.setSex(rs.getString("sex"));
user.setHome(rs.getString("home"));
user.setInfo(rs.getString("info"));
list.add(user);
}
DBUtil.closeConn();
return list;
}catch(SQLException e) {
e.printStackTrace();
}
return null;
} public boolean update(int id,String name,String pwd,String sex,String home,String info) {
boolean flag = false;
DBUtil.init();
String sql = "update user set name ='"+name
+"' , pwd ='"+pwd
+"' , sex ='"+sex
+"' , home ='"+home
+"' , info ='"+info+"' where id = "+id;
int i =DBUtil.addUpdDel(sql);
if(i>0) {
flag = true;
}
DBUtil.closeConn();
return flag;
} public boolean delete(int id) {
boolean flag = false;
DBUtil.init();
String sql = "delete from user where id="+id;
int i = DBUtil.addUpdDel(sql);
if(i>0) {
flag = true;
}
DBUtil.closeConn();
return flag;
} }
package entity;

public class User {

    private int id;
private String name;
private String pwd;
private String sex;
private String home;
private String info; public int getId() {
return id;
}
public void setId(int id) {
this.id=id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name=name;
}
public String getPwd() {
return pwd;
}
public void setPwd(String pwd) {
this.pwd=pwd;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex=sex;
}
public String getHome() {
return home;
}
public void setHome(String home) {
this.home=home;
}
public String getInfo() {
return info;
}
public void setInfo(String info) {
this.info=info;
} }
package servlet;

import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import dao.UserDao;
import dao.UserDaoImpl; public class DeleteServlet extends HttpServlet{
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String id = request.getParameter("id");
int userId = Integer.parseInt(id); UserDao ud = new UserDaoImpl(); if(ud.delete(userId)) {
request.setAttribute("xiaoxi", "删除成功");
request.getRequestDispatcher("/Searchall").forward(request, response);
}else {
response.sendRedirect("index.jsp");
}
} }
package servlet;

import java.io.IOException;
//import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
//import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import dao.UserDao;
import dao.UserDaoImpl; public class DengLuServlet extends HttpServlet{ public void doGet(HttpServletRequest request,HttpServletResponse response)
throws ServletException,IOException {
doPost(request,response);
} public void doPost(HttpServletRequest request,HttpServletResponse response)
throws ServletException,IOException {
String name = request.getParameter("name");
String pwd = request.getParameter("pwd");
UserDao ud = new UserDaoImpl(); if(ud.login(name, pwd)) {
request.setAttribute("xiaoxi", "欢迎用户"+name);
request.getRequestDispatcher("/success.jsp").forward(request,response);
}else {
response.sendRedirect("index.jsp");
}
} }
package servlet;

import java.util.List;
import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import dao.UserDao;
import dao.UserDaoImpl;
import entity.User; public class SearchallServlet extends HttpServlet{
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
UserDao ud = new UserDaoImpl();
List<User> userAll = ud.getUserAll();
request.setAttribute("userAll", userAll);
request.getRequestDispatcher("/showall.jsp").forward(request, response);
}
}
package servlet;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import dao.UserDao;
import dao.UserDaoImpl;
import entity.User; public class ZhuCeServlet extends HttpServlet{ public void doGet(HttpServletRequest request,HttpServletResponse response)
throws ServletException,IOException {
doPost(request,response);
}
public void doPost(HttpServletRequest request,HttpServletResponse response)
throws ServletException,IOException {
String name = request.getParameter("name");
String pwd = request.getParameter("pwd");
String sex = request.getParameter("sex");
String home = request.getParameter("home");
String info = request.getParameter("info"); User user = new User();
user.setName(name);
user.setPwd(pwd);
user.setSex(sex);
user.setHome(home);
user.setInfo(info); UserDao ud = new UserDaoImpl(); if(ud.register(user)) {
request.setAttribute("username", name);
request.getRequestDispatcher("/denglu.jsp").forward(request, response);
}else {
response.sendRedirect("index.jsp");
}
} }

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