JavaWeb学习笔记--day14--注册案例
day13复习
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
项目目录结构
数据库设计
略，选用SQLServer，UserDemo数据库中Users(username,password)表
注册流程图
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="