一，需求分析
整体分析框架如下图，需要的包也如下图，它们放在src下
所有的需求如下图所示，
1，我们创建一个名为day12的数据库，其中创建了一个users表
2,在myeclipse中我们新建一个名为day12_user的web项目，
3，在src下我们创建了如下几个java包：
com.itheima.damain 实体类包， 其中包括 User类
com.itheima.dao 接口包 ， 其中包括 UserDao接口
com.itheima.dao.impl 接口实现类包， 其中包括 UserDaoImpl实现类
com.itheima.service 接口包 其中包括service接口
com.itheima.service.impl 接口实现类包 其中包括service接口实现类
com.itheima.utils 工具包 其中包括一般的关闭，连接数据库的函数
com.itheima.exception 异常包
com.itheima.web.servlet servlet包 包括loginServlet和registerServlet
首先是主页main.jsp
<body> <h1>欢迎来到主页h1> <form action="/day12_user/login.jsp" method = "post"> <input type = "submit" value = "登陆" > form> <form action="/day12_user/register.jsp" method = "post"> <input type = "submit" value= "注册"> form> body>
对于登陆板块，选择登陆按钮，进入login.jsp
<body> <form action="/day12_user/demo1" method= "post"> 用户名：<input type = "text" name = "username" ><br> 密码：<input type = "password" name = "password" ><br> <input type = "submit" value = "登陆"><br> form> body>
web.xml如下图所示
<servlet> <servlet-name>loginServletservlet-name> <servlet-class>com.itheima.web.servlet.loginServletservlet-class> servlet> <servlet> <servlet-name>registerServletservlet-name> <servlet-class>com.itheima.web.servlet.registerServletservlet-class> servlet> <servlet-mapping> <servlet-name>loginServletservlet-name> <url-pattern>/demo1url-pattern> servlet-mapping> <servlet-mapping> <servlet-name>registerServletservlet-name> <url-pattern>/demo2url-pattern> servlet-mapping>
关于user用户的板块，com.itheima.damain 实体类包， 其中包括 User类，源码如下文所示
//实体bean,用于封装数据 public class User { private int id; private String username; private String password; private String email; private Date birthday; public User(String username, String password, String email, Date birthday) { super(); this.username = username; this.password = password; this.email = email; this.birthday = birthday; } public User() { // TODO Auto-generated constructor stub } public int getId() { return id; } public String getUsername() { return username; } public String getPassword() { return password; } public String getEmail() { return email; } public Date getBirthday() { return birthday; } }
com.itheima.web.servlet servlet包 包括loginServlet和registerServlet
loginservlet的源码如下图所示，只写一个完整源码，其他的servlet类似
package com.itheima.web.servlet; import java.io.IOException; import java.io.PrintWriter; import java.util.Random; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.itheima.damain.User; import com.itheima.service.impl.UserService; import com.itheima.service.impl.UserServiceImpl; @SuppressWarnings("serial") public class loginServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { //设置编码模式
request.setCharacterEncoding("UTF-8"); response.setContentType("text/html;charset=UTF-8"); PrintWriter out = response.getWriter(); //获取表单数据, 并将表单数据存入到login函数中 String name = request.getParameter("username"); String pwd = request.getParameter("password"); //处理业务逻辑，实现login 方法，里面涉及到finduser方法 UserService us = new UserServiceImpl();// User u = us.login(name,pwd); //分发转向 if(u!=null){ out.write("
欢迎你，登陆成功，3秒跳转首页"); request.setAttribute("u", u.getUsername()); request.getRequestDispatcher("/success.jsp").forward(request, response); }else{ //实现刷新功能 out.write("用户名或密码错误，请重新登陆"); response.setHeader("refresh", "1;url=/day12_user/login.jsp"); } } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }
上面是登陆成功后的主页，其源码为success.jsp
<body> <h1>这是主页h1> 欢迎 ${u} ，来到主页 body>
对于loginservlet中，有一句代码进行解析
//处理业务逻辑，实现login 方法，里面涉及到finduser方法
UserService us = new UserServiceImpl(); 这句是创建父接口指向子类对象 User u = us.login(name,pwd);
com.itheima.service 接口包 其中包括Userservice接口,
com.itheima.service.impl 接口实现类包 其中包括UserserviceImpl接口实现类
userService源代码如下
public interface UserService { //根据用户和密码实现登陆 public User login(String name,String pwd); //注册 public int register(User user); }
UserServiceImpl实现类源码如下：
package com.itheima.service.impl; import com.itheima.damain.User; import com.itheima.dao.UserDao; import com.itheima.dao.impl.UserDaoImpl; public class UserServiceImpl implements UserService{ // 实现用户登录的方法 public User login(String name,String pwd) { // TODO Auto-generated method stub //用实现类来指向父类的接口 UserDao dao = new UserDaoImpl(); return dao.finduser(name,pwd); } public int register(User user) { // TODO Auto-generated method stub UserDao dao = new UserDaoImpl(); return dao.adduser(user); } }
UserDao接口源码如下
public interface UserDao { // 查找用户 public User finduser(String name,String password); // 添加用户 public int adduser(User user); }
UserDaoImpl源码如下：
package com.itheima.dao.impl; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.text.SimpleDateFormat; import com.itheima.damain.User; import com.itheima.dao.UserDao; import com.itheima.utils.DBUtils; /** * 数据访问层对于方法的实现 * @author zjf-pc * */ public class UserDaoImpl implements UserDao{ /** * 查找用户的实现方法 */ public User finduser(String name,String password) { // TODO Auto-generated method stub Connection conn = null; PreparedStatement ps = null; ResultSet rs = null; User u = null; try { conn = DBUtils.getConnection(); //找到与浏览器中getConnection输入用户名和密码一致的sql语句，并保存在rs中 String sql = "select * from users where username= ? and password = ?"; ps = conn.prepareStatement(sql); ps.setString(1,name); ps.setString(2, password); //得到sql中的结果 rs = ps.executeQuery(); while(rs.next()) { //新创建一个user对象，将rs中的属性均赋值给user对象 //如果之前的rs内容为空的话，那么此时返回的u也为null u = new User(); u.setId(rs.getInt(1)); u.setUsername(rs.getString(2)); u.setPassword(rs.getString(3)); u.setEmail(rs.getString(4)); u.setBirthday(rs.getDate(5)); } } catch (Exception e) { e.printStackTrace(); }finally{ DBUtils.closeAll(rs, ps, conn); } return u; } /** * 添加用户的实现方法 */ public int adduser(User user) { // TODO Auto-generated method stub Connection conn = null; PreparedStatement ps = null; ResultSet rs = null; int i =0; try{ conn = DBUtils.getConnection(); //向数据库库表中插入一行语句如下 String sql = "insert into users(username,password,email,birthday)values(?,?,?,?);"; ps = conn.prepareStatement(sql); ps.setString(1, user.getUsername()); ps.setString(2, user.getPassword()); ps.setString(3, user.getEmail()); SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-DD"); ps.setString(4, sdf.format(user.getBirthday())); //将数据更新到表中 i = ps.executeUpdate(); } catch (Exception e) { e.printStackTrace(); }finally{ DBUtils.closeAll(rs, ps, conn); } return i; } public UserDaoImpl() { super(); // TODO Auto-generated constructor stub } }
对于用户注册板块，register.jsp如下图所示
<body> <h1>用户注册页面h1> <form action="/day12_user/demo2" method = "post"> 用户名：<input type = "text" name = "username"/><br> 密码： <input type = "password" name = "password"/><br> 邮箱：<input type = "text" name = "email"/><br> 出生日期：<input type = "text" name = "birthday"/><br> <input type = "submit" value = "注册"><br> form> body>
//web.xml中对应的是这个，那么相应的registerServlet会在下文看到
<servlet-mapping>
<servlet-name>registerServletservlet-name> <url-pattern>/demo2url-pattern> servlet-mapping>
registerServlet源码如下文所示
public class registerServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置编码模式 request.setCharacterEncoding("UTF-8"); response.setContentType("text/html;charset=UTF-8"); PrintWriter out = response.getWriter(); int i =0; //获取表单数据 String name = request.getParameter("username"); String pwd = request.getParameter("password"); String email = request.getParameter("email"); String birthday = request.getParameter("birthday"); SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-DD"); try { //将获取到的表单数据封装到u中 User u = new User(name,pwd,email, sdf.parse(birthday)); UserService us = new UserServiceImpl();//这在上文有解析 //对封装在u中的数据进行注册，使其记录在数据库表中 i = us.register(u);//这也在上文有解析 if(i!=0) { out.write("注册成功,信息如下：
"); out.write("
姓名："+u.getUsername()); out.write("
邮箱："+u.getEmail()); out.write("
出生日期："+sdf.format(u.getBirthday())); }else { out.write("注册信息不成功"); } } catch (Exception e) { e.printStackTrace(); } //处理业务逻辑 //分发转向 } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }