JavaWeb学习笔记--day14--注册案例

day13复习

JavaWeb学习笔记--day14--注册案例_第1张图片

功能分析

页面及功能概述
JSP:
login.jsp 登录页面
regist.jsp 注册页面,服务器表单验证,注册成功添加跳转到登录的超链接,验证码
Servlet
RegistServlet
VerifyCodeServlet
Service
UserException 用户异常
UserService 与用户相关的业务类
VerifyCode 验证码类,个人编写的,也可以使用itcast包中的验证码类
Dao:
JdbcUtils 数据库连接工具类,单例模式
UserDao 与用户相关的数据类
Domain:
User(对应数据库,还要对应表单)
所导jar包
JavaWeb学习笔记--day14--注册案例_第2张图片
项目目录结构
JavaWeb学习笔记--day14--注册案例_第3张图片
数据库设计
略,选用SQLServer,UserDemo数据库中Users(username,password)表

注册流程图
JavaWeb学习笔记--day14--注册案例_第4张图片

Domain层实现

user类

/*
 * dao-与用户相关的实体类
 * 对应数据库,还对应相应表单
 */
public class User {
	private String username;
	private String password;
	private String verifyCode;
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public String getVerifyCode() {
		return verifyCode;
	}
	public void setVerifyCode(String verifyCode) {
		this.verifyCode = verifyCode;
	}
	public User() {
		super();
	}
	public User(String username, String password, String verifyCode) {
		super();
		this.username = username;
		this.password = password;
		this.verifyCode = verifyCode;
	}
	@Override
	public String toString() {
		return "User [username=" + username + ", password=" + password + ", verifyCode=" + verifyCode + "]";
	}
	
}

Dao层实现

JdbcUtils类

/*
 * 连接SQLServer数据库的工具类
 * 单例模式
 */
public final class JdbcUtils {
	private String url = "jdbc:sqlserver://127.0.0.1:1433;DatabaseName=UserDemo";
	private String user = "sa";
	private String password = "123456";
	private JdbcUtils() {
		super();
	}
	private static JdbcUtils instance = null;
	//获取实例
	public static JdbcUtils getInstance() {
		if(instance==null) {
			synchronized (JdbcUtils.class) {//并发知识 加锁
				if(instance==null) {//双重检查 
					instance=new JdbcUtils();//延迟加载			
				}
			}
		}	
		return instance;
	}
	//静态代码段,实现注册驱动
	static {
		try {
			Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
		} catch (Exception e) {
			// TODO: handle exception
			throw new ExceptionInInitializerError(e);
		}
	}
	//获得连接
	public Connection getConnection() throws SQLException {
		return DriverManager.getConnection(url, user, password);
	}
	//释放资源
	public void free(ResultSet rs, PreparedStatement psmt, Connection con) {
		try {
			if(rs!=null)
			rs.close();
		} catch (SQLException e) {
			e.printStackTrace();
		} finally {
			try {
				psmt.close();
			} catch (SQLException e) {
				e.printStackTrace();
			} finally {
				try {
					con.close();
				} catch (SQLException e) {
					e.printStackTrace();
				}
			}
		}
	}
}

UserDao类

/*
 * 与用户相关的数据类
 */
public class UserDao {
	/*
	 * 根据用户名查询
	 * 1.调用JdbcUtils获得连接
	 * 2.得到prepareStatement
	 * 3.对占位符进行设值
	 * 4.得到结果并处理
	 * 5.释放资源
	 */
	public User searchUser(String username) {
		Connection con = null;
		PreparedStatement psmt = null;
		ResultSet rs = null;
		String sql = "select * from users where username like ?";
		JdbcUtils ju = JdbcUtils.getInstance();
		try {
			con = ju.getConnection();
			psmt=con.prepareStatement(sql);
			psmt.setString(1, username);
			rs = psmt.executeQuery();
			User u = new User();
			while(rs.next()) {
				u.setUsername(rs.getString(1));
				u.setPassword(rs.getString(2));
			}
			return u;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			throw new RuntimeException(e);
		} finally {
			ju.free(rs, psmt, con);
		}
	}
	/*
	 * 插入用户
	 */
	public void addUser(User user) {
		Connection con = null;
		PreparedStatement psmt = null;
		ResultSet rs = null;
		JdbcUtils ju = JdbcUtils.getInstance();
		String addSql = "insert into users values(?,?)";
		try {
			con = ju.getConnection();
			psmt= con.prepareStatement(addSql);
			psmt.setString(1, user.getUsername());
			psmt.setString(2, user.getPassword());
			psmt.execute();
			System.out.println("插入成功");
		} catch (Exception e) {
			// TODO: handle exception
			throw new RuntimeException(e);
		} finally {
			ju.free(rs, psmt, con);
		}
	}
}

Service层实现

UserException类

/*
 * 用户异常类
 */
public class UserException extends Exception {

	public UserException() {
		// TODO Auto-generated constructor stub
	}

	public UserException(String arg0) {
		super(arg0);
		// TODO Auto-generated constructor stub
	}

	public UserException(Throwable arg0) {
		super(arg0);
		// TODO Auto-generated constructor stub
	}

	public UserException(String arg0, Throwable arg1) {
		super(arg0, arg1);
		// TODO Auto-generated constructor stub
	}
}

UserService

public class UserService {
	UserDao ud =new UserDao();
	/*
	 * 注册功能
	 * 使用用户名去查询,如果返回null,完成添加
	 * 如果返回不是空 抛出异常
	 */
	public void regist(User user) throws UserException {
		User _user = ud.searchUser(user.getUsername());
		if(_user.getUsername()!=null) throw new UserException("用户名"+user.getUsername()+"已被注册");
		ud.addUser(user);
	}
}

VerifyCode类

public class VerifyCode {
	private int w = 70;
	private int h = 35;
	private Random r = new Random();
	private String[] fontNames = {"宋体","华文楷体","微软雅黑","楷体_GB2312"};
	//可选字符,无1liI;
	private String codes = "23456789abcdefghjkmnopqrstuvwxyzABCDEFGHJKLMNOPQRSTUVWXYZ";
	//背景色
	private Color bgColor = new Color(255,255,255);
	//验证码上的文本
	private String text;
	
	//随机获得颜色
	private Color randomColor() {
		int R = r.nextInt(150);
		int G = r.nextInt(150);
		int B = r.nextInt(150);
		return new Color(R,G,B);
	}
	//获得随机字体
	private Font randomFont() {
		int index = r.nextInt(fontNames.length);//随机得到字体数组中的一个
		String fontName = fontNames[index];
		int style = r.nextInt(4);//生成随机样式:0(无样式),1(粗体),2(斜体),3(粗体加斜体)
		int size = r.nextInt(5)+24;//生成随机字号,24~28
		return new Font(fontName, style, size);
	}
	
	//画干扰线
	private void drawLine (BufferedImage image) {
		int num = 3;//一共画三条
		Graphics2D g2 = (Graphics2D) image.getGraphics();
		for (int i = 0; i < num; i++) {//生成两个点的坐标
			int x1 = r.nextInt(w);
			int y1 = r.nextInt(h);
			int x2 = r.nextInt(w);
			int y2 = r.nextInt(h);
			g2.setStroke(new BasicStroke(1.5F));
			g2.setColor(Color.BLUE);//蓝色干扰线
			g2.drawLine(x1, y1, x2, y2);//画线
		}
	}
	
	//随机生成一个字符
	private char randomChar() {
		int index = r.nextInt(codes.length());
		return codes.charAt(index);//获取字符串的第index个字符
	}
	
	private BufferedImage createImg() {
		BufferedImage image = new BufferedImage(w,h,BufferedImage.TYPE_INT_RGB);
		Graphics2D g2 = (Graphics2D) image.getGraphics();
		g2.setColor(this.bgColor);
		g2.fillRect(0, 0, w, h);
		return image;
	}
	
	//调用这个方法得到验证码
	public BufferedImage getImg() {
		BufferedImage image = createImg();//创建图片缓冲区
		Graphics2D g2 = (Graphics2D) image.getGraphics();//得到绘制环境
		StringBuilder sb = new StringBuilder();//用来装载生成的验证码文本
		//向图片中画4个字符
		for (int i = 0; i < 4; i++) {
			String s =randomChar() + "";//随机生成一个字母
			sb.append(s);//把字母添加到sb中
			float x = i*1.0F *w/4;//设置当前字符的x轴坐标
			g2.setFont(randomFont());//设置随机字体
			g2.setColor(randomColor());//设置随机颜色
			g2.drawString(s, x, h-5);//画图
		}
		this.text = sb.toString();//把生成的字符串赋给this.text
		drawLine(image);//添加干扰线
		return image;
	}
	
	//返回验证码图片上的文本
	public String getText() {
		return text;
	}
	
	//保存图片到指定的输出流
	public static void output(BufferedImage image, OutputStream out) throws IOException {
		ImageIO.write(image,"JPEG",out);
	}
}

Servlet层实现

VerifyCode类

@WebServlet("/VerifyCodeServlet")
public class VerifyCodeServlet extends HttpServlet {
	@Override
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		//生成图片
		//保存图片上的文本到Session域中
		//把图片响应给客户端
		VerifyCode vc = new VerifyCode();
		BufferedImage bi = vc.getImg();
		VerifyCode.output(bi, response.getOutputStream());
		request.getSession().setAttribute("session_code", vc.getText());
	}
}

RegistServlet类

@WebServlet("/RegistServlet")
public class RegistServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		//处理编码
		request.setCharacterEncoding("utf-8");
		response.setContentType("text/html;charset=utf-8");
			
		//依赖UserService
		UserService us =new UserService();
		
		/*
		 * 封装表单数据到User对象中
		 * 
		 */
		User form = CommonUtils.toBean(request.getParameterMap(), User.class);
		
		/*
		 * 服务器端表单验证
		 * 1.创建一个Map,用来装载所有表单错误信息
		 * 2.在校验过程中,如果失败,向map添加错误信息,其中key为表单字段名
		 * 3.校验之后查看map长度是否大于0,如果大于零证明有错误信息,保存map到request中,
		 * 4.保存form到request中,转发到regist.jsp中
		 * 5.如果map为空,向下执行
		 */
		Map<String,String> errors = new HashMap<String,String>();
		//用户名格式校验
		String username = form.getUsername();//获取表单中的username
		if(username == null||username.trim().isEmpty()) {
			errors.put("username", "用户名不能为空!");
		}else if(username.length() < 3||username.length() > 15) {
			errors.put("username", "用户名长度必须在3~15之间!");
		}
		//密码格式校验
		String password = form.getPassword();//获取表单中的password
		if(password == null||password.trim().isEmpty()) {
			errors.put("password", "密码不能为空!");
		}else if(password.length() < 3||password.length() > 15) {
			errors.put("password", "密码长度必须在3~15之间!");
		}
		
		//对验证码进行校验
		String sessionCode = (String)request.getSession().getAttribute("session_code");
		String verifyCode = form.getVerifyCode();//获取表单中的VerifyCode
		if(verifyCode == null||verifyCode.trim().isEmpty()) {
			errors.put("verifyCode", "验证码不能为空!");
		}else if(verifyCode.length() != 4) {
			errors.put("verifyCode", "验证码长度必须为4!");
		}else if(verifyCode.equalsIgnoreCase(sessionCode) ) {
			errors.put("verifyCode", "验证码错误!");
		}
		
		//判断map是否为空,不为空说明有问题
		if(errors != null && errors.size() > 0) {//健壮性
			/*
			 * 1.保存errors到request域
			 * 2.保存form到request域,用于回显
			 * 3.转发到regist.jsp
			 */
			request.setAttribute("errors", errors);
			request.setAttribute("user", form);
			request.getRequestDispatcher("/user/regist.jsp").forward(request, response);
			return;
			
		}
		/*
		 * 调用us的方法 传递form过去
		 * 得到异常:获取异常信息,保存到request域中,转发到regist.jsp中显示
		 * 没有异常:输出注册成功
		 */
		try {
			us.regist(form);
			response.getWriter().print("

注册成功!

点击这里去登陆"
); } catch (UserException e) { //获取异常信息保存到request域中,并且转发到注册页面 request.setAttribute("msg", e.getMessage()); request.setAttribute("user", form);//用来在表单中回显,EL表达式特点,没有啥也不显示,不是NULL request.getRequestDispatcher("/user/regist.jsp").forward(request, response); } } }

页面代码实现

regist.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>    
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<script type="text/javascript">
function _change(){
	/*
	得到img元素
	修改其src为/LoginDemo/VerifyCodeServet
	*/
	var imgEle = document.getElementById("img");
	imgEle.src = "${pageContext.request.contextPath }/VerifyCodeServlet?a="+new Date().getTime();//不加个时间会因为浏览器缓存而更换失败
}
</script>
</head>
<body>
<%--<c:url value='/RegistServlet'/> --%>
<%--${pageContext.request.contextPath }/RegistServlet --%>
<%
	String message = " ";
	String msg = (String)request.getAttribute("msg");
	if(msg !=null){
		message = msg;
	}
%>
<h1>注册</h1>
<font color="red"><b><%= message%></b></font>
<form method="post" action="${pageContext.request.contextPath }/RegistServlet">
用户名:<input type="text" name="username" value="${user.username}"/>${errors.username }<br/>
密  码:<input type="password" name="password" value="${user.password}"/>${errors.password }<br/>
验证码:<input type="text" name="verifyCode" size="3"/>
<img id="img" src="${pageContext.request.contextPath }/VerifyCodeServlet"/>
<a href="javascript:_change()">换一张</a>${errors.verifyCode }<br/>
<input type="submit" value="注册" />
</form>
</body>
</html>

login.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<%--${pageContext.request.contextPath }/LoginServlet --%>
<form method="post" action="">
用户名:<input type="text" name="username"/><br/>
密  码:<input type="password" name="password"/><br/>
<input type="button" value="登录"/>
</form>
</body>
</html>

你可能感兴趣的:(WEB学习)