实现用户管功能
刚刚访问密码直接走前端
现在要发起请求走Servlet，Servlet处理后返回前端页面
Servlet
- 处理请求
- 调用业务
- 返回页面
业务要查询用户列表，查询角色列表，为了实现分页，需查询pageSize总数。查询从Service层到Dao层，Dao层从数据库里面查
1、导入分页的工具类
2、用户列表页面导入
为了我们职责统一，可以把角色的操作单独放在一个包中，和Pojo类一一对应
1、获取用户数量
UserDao
//查询用户总数
public int getUserCount(Connection connection,String username,int userRole) throws SQLException;
//通过条件查询-userlist
public List<User> getUserList(Connection connection,String userName,int userRole,int currentPageNo,int pageSize)throws Exception;
- UserDaoImpl
//根据用户名或者角色查询用户总数
public int getUserCount(Connection connection, String username, int userRole) throws SQLException {
PreparedStatement pstm=null;
ResultSet rs=null;
int count=0;
if(connection!=null){
StringBuffer sql=new StringBuffer();
sql.append("select count(1) as count from smbms_user u,smbms_role r where u.userRole=r.id");
ArrayList<Object> list=new ArrayList<Object>();
if(!StringUtils.isNullOrEmpty(username)){
sql.append(" and u.userName like ?");
list.add("%"+username+"%");
}
if(userRole>0){
sql.append(" and u.userRole= ?");
list.add(userRole);
}
//list转化为数组
Object[] params=list.toArray();
System.out.println("UserDaoImpl->getUserCount:"+sql.toString());
rs = BaseDao.execute(connection, pstm, rs, sql.toString(), params);
if(rs.next()){
//从结果集中获取最终的数量
count = rs.getInt("count");
}
BaseDao.closeResource(null,pstm,rs);
}
return count;
}
public List<User> getUserList(Connection connection, String userName, int userRole, int currentPageNo, int pageSize) throws Exception {
// TODO Auto-generated method stub
PreparedStatement pstm = null;
ResultSet rs = null;
List<User> userList = new ArrayList<User>();
if(connection != null){
StringBuffer sql = new StringBuffer();
sql.append("select u.*,r.roleName as userRoleName from smbms_user u,smbms_role r where u.userRole = r.id");
List<Object> list = new ArrayList<Object>();
if(!StringUtils.isNullOrEmpty(userName)){
sql.append(" and u.userName like ?");
list.add("%"+userName+"%");
}
if(userRole > 0){
sql.append(" and u.userRole = ?");
list.add(userRole);
}
sql.append(" order by creationDate DESC limit ?,?");
currentPageNo = (currentPageNo-1)*pageSize;
list.add(currentPageNo);
list.add(pageSize);
Object[] params = list.toArray();
System.out.println("sql ----> " + sql.toString());
rs = BaseDao.execute(connection, pstm, rs, sql.toString(), params);
while(rs.next()){
User _user = new User();
_user.setId(rs.getInt("id"));
_user.setUserCode(rs.getString("userCode"));
_user.setUserName(rs.getString("userName"));
_user.setGender(rs.getInt("gender"));
_user.setBirthday(rs.getDate("birthday"));
_user.setPhone(rs.getString("phone"));
_user.setUserRole(rs.getInt("userRole"));
_user.setUserRoleName(rs.getString("userRoleName"));
userList.add(_user);
}
BaseDao.closeResource(null, pstm, rs);
}
return userList;
}
- UserService
//查询记录数
public int getUserCount(String userName,int userRole);
public List<User> getUserList(String queryUserName, int queryUserRole, int currentPageNo, int pageSize);
- UserServiceImpl
//查询记录数
public int getUserCount(String userName, int userRole) {
Connection connection = null;
int count=0;
try {
connection=BaseDao.getConnection();
count=userDao.getUserCount(connection,userName,userRole);
} catch (SQLException e) {
e.printStackTrace();
}finally {
BaseDao.closeResource(connection,null,null);
}
return count;
}
public List<User> getUserList(String queryUserName, int queryUserRole, int currentPageNo, int pageSize) {
// TODO Auto-generated method stub
Connection connection = null;
List<User> userList = null;
System.out.println("queryUserName ---- > " + queryUserName);
System.out.println("queryUserRole ---- > " + queryUserRole);
System.out.println("currentPageNo ---- > " + currentPageNo);
System.out.println("pageSize ---- > " + pageSize);
try {
connection = BaseDao.getConnection();
userList = userDao.getUserList(connection, queryUserName,queryUserRole,currentPageNo,pageSize);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
BaseDao.closeResource(connection, null, null);
}
return userList;
}
@Test
public void test1(){
UserServiceImpl userService = new UserServiceImpl();
int userCount=userService.getUserCount(null,0);
System.out.println(userCount);
}
2、获取角色数量
在Dao层和Service层都新增role部分
RoleDao
public interface RoleDao {
//获取角色列表
public List<Role> getRoleList(Connection connection)throws SQLException;
}
RoleDaoImpl
package com.lding.dao.role;
import com.lding.dao.BaseDao;
import com.lding.pojo.Role;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
/**
* @program: SMBMS
* @description:
* @author: 王丁
* @date: 2021-11-09 15:39
**/
public class RoleDaoImpl implements RoleDao{
public List<Role> getRoleList(Connection connection) throws SQLException {
PreparedStatement pstm = null;
ResultSet rs = null;
ArrayList<Role> roleList = new ArrayList<Role>();
if (connection != null) {
String sql = "select * from smbms_role";
Object[] params = {};
rs = BaseDao.execute(connection, pstm, rs, sql, params);
while (rs.next()) {
Role _role = new Role();
_role.setId(rs.getInt("id"));
_role.setRoleCode(rs.getString("roleCode"));
_role.setRoleName(rs.getString("roleName"));
roleList.add(_role);
}
BaseDao.closeResource(null, pstm, rs);
}
return roleList;
}
}
RoleService
public interface RoleService {
//获取角色列表
public List<Role> getRoleList();
}
RoleServiceImpl
public class RoleServiceImpl implements RoleService {
//引入Dao
private RoleDao roleDao;
public RoleServiceImpl(){
roleDao=new RoleDaoImpl();
}
public List<Role> getRoleList() {
Connection connection = null;
List<Role> roleList=null;
try {
connection=BaseDao.getConnection();
roleList = roleDao.getRoleList(connection);
} catch (SQLException e) {
}finally {
BaseDao.closeResource(connection,null,null);
}
return roleList;
}
@Test
public void test(){
RoleServiceImpl roleService=new RoleServiceImpl();
List<Role> roleList=roleService.getRoleList();
for(Role role:roleList){
System.out.println(role.getRoleName());
}
}
}
和之前的实现思路一样，我们先在Dao层实现对数据库中信息的提取，然后在Service层直接调用Dao层中的方法
以角色查询为例，在DaoImpl实现方法中创建PrepareStatement预编译对象，rs结果集对象，
roleList存储角色列表，通过传过来的连接，编写查询role的sql语句，然后执行Dao的execute方法
得到rs结果集后遍历rs结果集，取出每个role对象，存储到roleList，然后返回roleList
RoleServiceImpl直接调用Dao层中的getRoleList方法
在service层创建与数据库的连接，然后调用getRoleList方法得到查询结果 最后关闭资源
拿到前端列表后，将所有数据通过req.setAttribute的方式存入属性中，前端也可以通过这个属性获取。
最后通过请求转发req.getRequestDispatcher(“userlist.jsp”).forward(req,resp);返回前端页面。
UserServlet完整代码
package com.lding.servlet.user;
import com.alibaba.fastjson.JSONArray;
import com.lding.pojo.Role;
import com.lding.pojo.User;
import com.lding.service.role.RoleService;
import com.lding.service.role.RoleServiceImpl;
import com.lding.service.user.UserServiceImpl;
import com.lding.util.Constants;
import com.lding.util.PageSupport;
import com.mysql.jdbc.StringUtils;
import javax.servlet.ServletException;
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.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* @program: SMBMS
* @description:
* @author: 王丁
* @date: 2021-11-06 20:49
**/
public class UserServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String method = req.getParameter("method");
if(method!=null&&method.equals("savepwd")){
updatePwd(req,resp);
}else if(method!=null&&method.equals("pwdmodify")){
pwdModify(req,resp);
}else if(method.equals("query")&&method!=null){
this.query(req,resp);
}
}
//重点难点
public void query(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//查询用户列表
//从前端获取数据
String queryUserName=req.getParameter("queryname");
String temp=req.getParameter("queryUserRole");
String pageIndex=req.getParameter("pageIndex");
List<User> userList=null;
int queryUserRole=0;
//获取用户列表
UserServiceImpl userService=new UserServiceImpl();
//第一次走这个请求，一定是第一页，页面大小是固定的
int pageSize=5; //可以把这个写在配置文件中，方便后期修改
int currentPageNo=1;
if(queryUserName==null){
queryUserName="";
}
if(temp!=null&&!temp.equals("")){
queryUserRole=Integer.parseInt(temp);//给查询赋值0，1，2，3
}
if(pageIndex!=null){
currentPageNo = Integer.parseInt(pageIndex);
}
//获取用户的总数(分页：上一页，下一页)
int totalCount= userService.getUserCount(queryUserName, queryUserRole);
//总页数支持
PageSupport pageSupport=new PageSupport();
pageSupport.setCurrentPageNo(currentPageNo);
pageSupport.setPageSize(pageSize);
pageSupport.setTotalCount(totalCount);
int totalPageCount=pageSupport.getTotalPageCount();
//控制首页和尾页
//如果页面要小于1了，就显示第一页的东西
if(currentPageNo<1){
currentPageNo=1;
}else if(currentPageNo>totalPageCount){
currentPageNo=totalPageCount;
}
//获取用户列表展示
userList = userService.getUserList(queryUserName, queryUserRole, currentPageNo, pageSize);
req.setAttribute("userList",userList);
//拿到角色列表
RoleServiceImpl roleService = new RoleServiceImpl();
List<Role> roleList = roleService.getRoleList();
req.setAttribute("roleList",roleList);
req.setAttribute("totalCount",totalCount);
req.setAttribute("currentPageNo",currentPageNo);
req.setAttribute("totalPageCount",totalPageCount);
req.setAttribute("queryUserName",queryUserName);
req.setAttribute("queryUserRole",queryUserRole);
//返回前端
req.getRequestDispatcher("userlist.jsp").forward(req,resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doGet(req,resp);
}
public void updatePwd(HttpServletRequest req, HttpServletResponse resp){
//获取参数往上提交
//从Session中拿用户ID
Object user = req.getSession().getAttribute(Constants.USER_SESSION);
String newpassword = req.getParameter("newpassword");
boolean flag=false;
if(user!=null&&newpassword!=null){
UserServiceImpl userService = new UserServiceImpl();
flag= userService.updatePwd(((User) user).getId(), newpassword);
if(flag){
req.setAttribute("message","修改密码成功，请退出重新登陆");
//密码修改成功 移除当前Session
req.getSession().removeAttribute(Constants.USER_SESSION);
//过滤器自动判断Session为null 重新回登陆页面
}else{
req.setAttribute("message","密码修改失败");
}
}else{
req.setAttribute("message","新密码有问题");
}
try {
req.getRequestDispatcher("pwdmodify.jsp").forward(req,resp);
} catch (ServletException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
public void pwdModify(HttpServletRequest req, HttpServletResponse resp){
//从Session里面拿ID
Object o=req.getSession().getAttribute(Constants.USER_SESSION);
String oldpassword=req.getParameter("oldpassword");
//万能的Map ：结果集
Map<String,String> resultMap=new HashMap<String, String>();
if(o==null){
//Session失效了，session过期了
resultMap.put("result","sessionerror");
}else if(StringUtils.isNullOrEmpty(oldpassword)){
resultMap.put("result","error");
}else{
String userPassword=((User)o).getUserPassword();//Session中的用户的密码
if(oldpassword.equals(userPassword)){
resultMap.put("result","true");
}else{
resultMap.put("result","false");
}
}
resp.setContentType("application/json");
try {
PrintWriter writer=resp.getWriter();
//JSONArray 阿里巴巴的JSON工具类，转换格式
/*
resultMap=["result","sessionerror"]
转化为Json格式={key:value}
*/
writer.write(JSONArray.toJSONString(resultMap));
writer.flush();
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}