导入Java包放在这个目录下
目录的流程:
登录流程
登录练习:
1、创建登录页面
创建Servlet进行登录页面请求处理
2、点击登录完成登录操作
浏览器发送请求到服务器(用户信息+其他数据)
服务器调用对应的servlet进行处理
设置响应编码格式
获取请求信息
处理请求信息
响应处理结果
3、在servlet中完成用户登录校验
需要连接数据库(在mySql中创建用户表)
使用MVC思想完成
1、创建登录页面
创建Servlet进行登录页面请求处理
package com.dym.servlet;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class PageServlet extends HttpServlet {@Overrideprotected void service(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {//设置相应编码格式resp.setContentType("text/html;charset=utf-8");//获取请求信息//处理请求//响应处理结果resp.getWriter().write("<html>");resp.getWriter().write("<head>");resp.getWriter().write("</head>");resp.getWriter().write("<body>");resp.getWriter().write("<form action='login' method='get'>");resp.getWriter().write("用户名：<input type='text' name='uname' value=''/><br/>");resp.getWriter().write("密码：<input type='password' name='pwd' value=''/><br/>");resp.getWriter().write("<input type='submit' value='登录'/><br/>");resp.getWriter().write("</form>");resp.getWriter().write("</body>");resp.getWriter().write("</html>");}}
2、点击登录完成登录操作
浏览器发送请求到服务器(用户信息+其他数据)
服务器调用对应的servlet进行处理
设置响应编码格式
获取请求信息
处理请求信息
响应处理结果
User.java
package com.dym.pojo;public class User {private int uid;private String uname;private String pwd;public int getUid() {return uid;}public void setUid(int uid) {this.uid = uid;}public String getUname() {return uname;}public void setUname(String uname) {this.uname = uname;}public String getPwd() {return pwd;}public void setPwd(String pwd) {this.pwd = pwd;}@Overridepublic String toString() {return "User [uid=" + uid + ", uname=" + uname + ", pwd=" + pwd + "]";}@Overridepublic int hashCode() {final int prime = 31;int result = 1;result = prime * result + ((pwd == null) ? 0 : pwd.hashCode());result = prime * result + uid;result = prime * result + ((uname == null) ? 0 : uname.hashCode());return result;}@Overridepublic boolean equals(Object obj) {if (this == obj)return true;if (obj == null)return false;if (getClass() != obj.getClass())return false;User other = (User) obj;if (pwd == null) {if (other.pwd != null)return false;} else if (!pwd.equals(other.pwd))return false;if (uid != other.uid)return false;if (uname == null) {if (other.uname != null)return false;} else if (!uname.equals(other.uname))return false;return true;}public User() {super();// TODO Auto-generated constructor stub}public User(int uid, String uname, String pwd) {super();this.uid = uid;this.uname = uname;this.pwd = pwd;}}
LoginService.java
package com.dym.service;import com.dym.pojo.User;public interface LoginService {User checkLoginService(String uname,String pwd);}
LoginServiceImpl.java
package com.dym.service.impl;import com.dym.dao.LoginDao;import com.dym.dao.impl.LoginDaoImpl;import com.dym.pojo.User;import com.dym.service.LoginService;public class LoginServiceImpl implements LoginService{//创建Dao层对象LoginDao ld=new LoginDaoImpl();@Overridepublic User checkLoginService(String uname, String pwd) {return ld.checkLoginDao(uname, pwd);}}
LoginDao.java
package com.dym.dao;import com.dym.pojo.User;public interface LoginDao {//根据用户名和密码获取用户信息User checkLoginDao(String uname,String pwd);//根据uid获取用户信息User checkUidDao(String uid);}
LoginDaoImpl.java
package com.dym.dao.impl;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import com.dym.dao.LoginDao;import com.dym.pojo.User;public class LoginDaoImpl implements LoginDao{@Overridepublic User checkLoginDao(String uname, String pwd) {//声明jdbc对象Connection conn=null;PreparedStatement ps=null;ResultSet rs=null;//声明数据存储对象User u=null;try {//加载驱动Class.forName("com.mysql.jdbc.Driver");//获取连接对象conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/wollo","root","123456");//创建sql命令String sql="select * from t_user where uname=? and pwd=?";//创建sql命令对象ps=conn.prepareStatement(sql);//给占位符赋值ps.setString(1, uname);ps.setString(2, pwd);//执行rs=ps.executeQuery();//遍历执行结果while(rs.next()){u=new User();u.setUid(rs.getInt("uid"));u.setUname(rs.getString("uname"));u.setPwd(rs.getString("pwd"));}} catch (Exception e) {e.printStackTrace();}finally{//关闭资源try {rs.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {ps.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {conn.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}return u;}//根据UID获取用户信息@Overridepublic User checkUidDao(String uid) {//声明Jdbc对象Connection conn=null;PreparedStatement ps=null;ResultSet rs=null;//声明数据存储对象User u=null;try {//加载驱动Class.forName("com.mysql.jdbc.Driver");//获取连接对象conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/407","root","1234");//创建Sql命令String sql="select * from t_user where uid=?";//创建Sql命令对象ps=conn.prepareStatement(sql);//给占位符赋值ps.setString(1, uid);//执行rs=ps.executeQuery();//遍历执行结果while(rs.next()){u=new User();u.setUid(rs.getInt("uid"));u.setUname(rs.getString("uname"));u.setPwd(rs.getString("pwd"));}//关闭资源} catch (Exception e) {e.printStackTrace();}finally{try {rs.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {ps.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {conn.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}//返回return u;}}
LoginServlet.java
package com.dym.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 com.dym.pojo.User;import com.dym.service.LoginService;import com.dym.service.impl.LoginServiceImpl;public class LoginServlet extends HttpServlet {@Overrideprotected void service(HttpServletRequest req, HttpServletResponse resp)throws ServletException, IOException {//设置响应编码格式resp.setContentType("text/html;charset=utf-8");//获取请求信息String uname=req.getParameter("uname");uname=new String(uname.getBytes("iso8859-1"),"utf-8"); //解决了乱码问题String pwd=req.getParameter("pwd");System.out.println(uname+":"+pwd);//处理请求信息//获取业务层对象LoginService ls=new LoginServiceImpl();User u=ls.checkLoginService(uname, pwd);System.out.println(u);//响应处理结果if(u!=null){resp.getWriter().write("登录成功");}else{resp.getWriter().write("登录失败");}}}
