目录
1、登陆用户名的显示
UserServlet程序中保存用户的登陆信息
protected void login(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// 1 获取请求的参数
String username = req.getParameter("username");
String password = req.getParameter("password");
// 2 调用UserService业务查询
User loginUser = userService.login(username, password);
if(loginUser == null) {
// 返回值为null，登陆失败
//回写错误信息和用户名
req.setAttribute("msg","用户名或密码错误!");
req.setAttribute("username",username);
// 跳转回登录页面
req.getRequestDispatcher("/pages/user/login.jsp").forward(req,resp);
} else {
// 返回值不为null，登陆成功
// 保存用户的登陆信息到session域中
req.getSession().setAttribute("user",loginUser);
// 跳转到登陆成功页面
req.getRequestDispatcher("/pages/user/login_success.jsp").forward(req,resp);
}
}修改登陆成功菜单显示数据（login_success_menu.jsp)
<div>
<span>欢迎<span class="um_span">${sessionScope.user.username}</span>光临尚硅谷书城</span>
<a href="pages/order/order.jsp">我的订单</a>
<a href="index.jsp">注销</a>
<a href="index.jsp">返回</a>
</div>修改登陆成功后首页显示数据（index.jsp)
<div>
<%--如果登陆未成功，显示【登陆】【注册】菜单--%>
<c:if test="${empty sessionScope.user}">
<a href="pages/user/login.jsp">登录</a> |
<a href="pages/user/regist.jsp">注册</a>
</c:if>
<%--如果登陆成功，显示【我的订单】【注销】菜单--%>
<c:if test="${not empty sessionScope.user}">
<span>欢迎<span class="um_span">${sessionScope.user.username}</span>光临尚硅谷书城</span>
<a href="pages/order/order.jsp">我的订单</a>
<a href="index.jsp">注销</a>
</c:if>
<a href="pages/cart/cart.jsp">购物车</a>
<a href="pages/manager/manager.jsp">后台管理</a>
</div>2、用户的登出
在UserServlet中添加logout方法
/**
* 登出/账户注销功能
* @param req
* @param resp
* @throws ServletException
* @throws IOException
*/
protected void logout(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// 1 销毁Session/清楚Session域中的用户信息
req.getSession().invalidate();
// 2 请求重定向
resp.sendRedirect(req.getContextPath());
}2、修改注销菜单的提交地址
<a href="userServlet?action=logout">注销</a>
3、用户注册验证码功能的实现
导入谷歌浏览器生成验证码的jar包
在web.xml中配置KaptchaServlet
<servlet>
<servlet-name>KaptchaServlet</servlet-name>
<servlet-class>com.google.code.kaptcha.servlet.KaptchaServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>KaptchaServlet</servlet-name>
<url-pattern>/kaptcha.jpg</url-pattern>
</servlet-mapping>
在注册页面显示验证码
<label>验证码：</label> <input class="itxt" type="text" style="width: 120px;" name="code" id="code"/> <img alt="" src="kaptcha.jpg" style="width: 100px; height:40px;float: right;margin-right: 40px">
在UserServlet中regist方法编写代码
protected void regist(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// 获取Session域中的验证码
String token = (String) req.getSession().getAttribute(KAPTCHA_SESSION_KEY);
// 删除Session域中的验证码
req.getSession().removeAttribute(KAPTCHA_SESSION_KEY);
// 1 获取参数
String username = req.getParameter("username");
String password = req.getParameter("password");
String email = req.getParameter("email");
String code = req.getParameter("code");
User user = new User();
WebUtils.copyParamToBean(req.getParameterMap(),user);
// 2 校验验证码
if(token != null && token.equalsIgnoreCase(code)) {
// 验证码正确
// 3 验证用户名是否存在
if(userService.existsUsername(username)) {
// 用户名不可用
System.out.println("用户名不可用");
//回写错误信息
req.setAttribute("msg","用户名已存在");
req.setAttribute("username",username);
req.setAttribute("email",email);
// 跳转回注册页面
req.getRequestDispatcher("/pages/user/regist.jsp").forward(req,resp);
} else {
// 用户名可用
// 保存注册信息
userService.registUser(new User(null,username,password,email));
// 跳转到注册成功页面
req.getRequestDispatcher("/pages/user/regist_success.jsp").forward(req,resp);
}
} else {
//验证码错误
System.out.println("验证码错误");
//回写错误信息
req.setAttribute("msg","验证码错误");
req.setAttribute("username",username);
req.setAttribute("email",email);
// 跳回注册页面
req.getRequestDispatcher("/pages/user/regist.jsp").forward(req,resp);
}
}4、验证码的切换
给验证码标签增加id属性
<img id="code_img" alt="" src="kaptcha.jpg" style="width: 100px;height:40px;float: right; margin-right: 40px">
给验证码绑定单击事件
// 给验证码图片绑定单击事件
$("#code_img").click(function () {
// this.src表示当前验证码img标签的图片路径，可读可写
// new Date()给验证码添加唯一性参数，使它可以不断更新
this.src = "${basePath}kaptcha.jpg?d=" + new Date();
});
5、购物车模块的实现
CartItem的编写
package pojo;
import java.math.BigDecimal;
/**
* @description:购物车的商品项
* @create 2022-01-19 20:28
*/
public class CartItem {
private Integer id;
private String name;
private Integer count;
private BigDecimal price;
private BigDecimal totalPrice;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getCount() {
return count;
}
public void setCount(Integer count) {
this.count = count;
}
public BigDecimal getPrice() {
return price;
}
public void setPrice(BigDecimal price) {
this.price = price;
}
public BigDecimal getTotalPrice() {
return totalPrice;
}
public void setTotalPrice(BigDecimal totalPrice) {
this.totalPrice = totalPrice;
}
public CartItem() {
}
public CartItem(Integer id, String name, Integer count, BigDecimal price, BigDecimal totalPrice) {
this.id = id;
this.name = name;
this.count = count;
this.price = price;
this.totalPrice = totalPrice;
}
@Override
public String toString() {
return "CartItem{" +
"id=" + id +
", name='" + name + '\'' +
", count=" + count +
", price=" + price +
", totalPrice=" + totalPrice +
'}';
}
}
Cart的编写
package pojo;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
/**
* @description:购物车对象
* @create 2022-01-19 20:32
*/
public class Cart {
// private Integer totalCount;
// private BigDecimal totalPrice;
private Map<Integer,CartItem> items = new LinkedHashMap<Integer,CartItem>();
public Integer getTotalCount() {
Integer totalCount = 0;
// 遍历购物车中所有商品
for (Map.Entry<Integer,CartItem> entry:items.entrySet()) {
totalCount += entry.getValue().getCount();// 累加所有的商品数量
}
return totalCount;
}
public BigDecimal getTotalPrice() {
BigDecimal totalPrice = new BigDecimal(0);
// 遍历购物车中所有商品
for (Map.Entry<Integer,CartItem> entry:items.entrySet()) {
totalPrice = totalPrice.add(entry.getValue().getTotalPrice());// 累加所有的商品数量
}
return totalPrice;
}
public Map<Integer, CartItem> getItems() {
return items;
}
public void setItems(Map<Integer, CartItem> items) {
this.items = items;
}
/**
* 增加商品的方法
* @param cartItem
*/
public void addItem(CartItem cartItem) {
//判断当前商品是否在购物车中，如果有，改变商品的数量和总价；如果没有，则添加进购物车中
CartItem item = items.get(cartItem.getId());
if (item != null) {
// 此商品已存在
item.setCount(item.getCount() + 1);//商品的数量+1
item.setTotalPrice(item.getPrice().multiply(new BigDecimal(item.getCount())));//商品的总价=单价*数量
} else {
// 此商品不存在
items.put(cartItem.getId(),cartItem);
}
}
/**
* 删除商品的方法
*/
public void deleteItem(Integer id) {
items.remove(id);
}
/**
* 清空商品
*/
public void clear( ) {
items.clear();
}
/**
* 修改商品的数量
*/
public void updateCount(Integer id,Integer count) {
// 判断商品是否存在在购物车中，如果存在，则修改商品的数量，更新总金额;
CartItem cartItem = items.get(id);
if (cartItem != null) {
cartItem.setCount(count);//修改商品的数量
cartItem.setTotalPrice(cartItem.getPrice().multiply(new BigDecimal(cartItem.getCount())));//修改商品的总金额
}
}
@Override
public String toString() {
return "Cart{" +
"totalCount=" + getTotalCount() +
", totalPrice=" + getTotalPrice() +
", items=" + items +
'}';
}
}
Cart类中方法的测试
package test;
import org.junit.Test;
import pojo.Cart;
import pojo.CartItem;
import java.math.BigDecimal;
import static org.junit.Assert.*;
/**
* @description:
* @create 2022-01-19 23:08
*/
public class CartTest {
@Test
public void addItem() {
Cart cart = new Cart();
cart.addItem(new CartItem(1,"Java从入门到精通",1,new BigDecimal(1000),new BigDecimal(1000)));
cart.addItem(new CartItem(1,"Java从入门到精通",1,new BigDecimal(1000),new BigDecimal(1000)));
cart.addItem(new CartItem(2,"数据结构与算法",1,new BigDecimal(100),new BigDecimal(100)));
System.out.println(cart);
}
@Test
public void deleteItem() {
Cart cart = new Cart();
cart.addItem(new CartItem(1,"Java从入门到精通",1,new BigDecimal(1000),new BigDecimal(1000)));
cart.addItem(new CartItem(1,"Java从入门到精通",1,new BigDecimal(1000),new BigDecimal(1000)));
cart.addItem(new CartItem(2,"数据结构与算法",1,new BigDecimal(100),new BigDecimal(100)));
cart.deleteItem(1);
System.out.println(cart);
}
@Test
public void clear() {
Cart cart = new Cart();
cart.addItem(new CartItem(1,"Java从入门到精通",1,new BigDecimal(1000),new BigDecimal(1000)));
cart.addItem(new CartItem(1,"Java从入门到精通",1,new BigDecimal(1000),new BigDecimal(1000)));
cart.addItem(new CartItem(2,"数据结构与算法",1,new BigDecimal(100),new BigDecimal(100)));
cart.clear();
System.out.println(cart);
}
@Test
public void updateCount() {
Cart cart = new Cart();
cart.addItem(new CartItem(1,"Java从入门到精通",1,new BigDecimal(1000),new BigDecimal(1000)));
cart.addItem(new CartItem(1,"Java从入门到精通",1,new BigDecimal(1000),new BigDecimal(1000)));
cart.addItem(new CartItem(2,"数据结构与算法",1,new BigDecimal(100),new BigDecimal(100)));
cart.updateCount(2,2);
System.out.println(cart);
}
}6、加入购物车功能的实现
给按钮绑定单击事件
<div class="book_add">
<button class="addToCart" bookId="${book.id}">加入购物车</button>
</div>
<script type="text/javascript">
$(function () {
$("button.addToCart").click(function () {
var bookId = $(this).attr("bookId");
location = "${basePath}cartServlet?action=addItem&id=" + bookId;
});
});
</script>
编写CartServlet类并在web.xml中配置地址
package web;
import pojo.Book;
import pojo.Cart;
import pojo.CartItem;
import service.BookService;
import service.impl.BookServiceImpl;
import utils.WebUtils;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.math.BigDecimal;
/**
* @description:
* @create 2022-01-20 10:38
*/
public class CartServlet extends BaseServlet{
private BookService bookService = new BookServiceImpl();
protected void addItem(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// 获取添加图书的编号
int bookid = WebUtils.parseInt(req.getParameter("id"), 0);
// 根据图书编号获取图书信息
Book book = bookService.queryBookById(bookid);
// 将图书信息转化成商品项
CartItem cartItem = new CartItem(book.getId(),book.getName(),1,book.getPrice(),book.getPrice());
// 调用addItem向购物车内添加商品
Cart cart = (Cart) req.getSession().getAttribute("cart");
if (cart == null) {
cart = new Cart();
req.getSession().setAttribute("cart",cart);
}
cart.addItem(cartItem);
System.out.println(cart);
System.out.println("Referer:" + req.getHeader("Referer"));
resp.sendRedirect(req.getHeader("Referer"));
}
}
<servlet>
<servlet-name>CartServlet</servlet-name>
<servlet-class>web.CartServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>CartServlet</servlet-name>
<url-pattern>/cartServlet</url-pattern>
</servlet-mapping>
7、购物车页面的显示
<div id="main">
<table>
<tr>
<td>商品名称</td>
<td>数量</td>
<td>单价</td>
<td>金额</td>
<td>操作</td>
</tr>
<%--购物车内的商品不为空--%>
<c:if test="${not empty sessionScope.cart.items}">
<%--遍历输出商品--%>
<c:forEach items="${sessionScope.cart.items}" var="entry">
<tr>
<td>${entry.value.name}</td>
<td>${entry.value.count}</td>
<td>${entry.value.price}</td>
<td>${entry.value.totalPrice}</td>
<td><a href="#">删除</a></td>
</tr>
</c:forEach>
</c:if>
<%--购物车内的商品为空--%>
<c:if test="${empty sessionScope.cart.items}">
<tr>
<td colspan="5"><a href="index.jsp">当前购物车为空，赶快去选购吧</a> </td>
</tr>
</c:if>
</table>
<c:if test="${not empty sessionScope.cart.items}">
<div class="cart_info">
<span class="cart_span">购物车*有<span class="b_count">${sessionScope.cart.totalCount}</span>件商品</span>
<span class="cart_span">总金额<span class="b_price">${sessionScope.cart.totalPrice}</span>元</span>
<span class="cart_span"><a href="#">清空购物车</a></span>
<span class="cart_span"><a href="pages/cart/checkout.html">去结账</a></span>
</div>
</c:if>
</div>8、购物车删除商品功能的实现
deleteItem方法的编写
protected void deleteItem(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// 获取要删除的商品id
int id = WebUtils.parseInt(req.getParameter("id"), 0);
// 获取购物车对象
Cart cart = (Cart) req.getSession().getAttribute("cart");
if (cart != null) {
// 删除购物车里的商品项
cart.deleteItem(id);
// 重定向回原来的页面
resp.sendRedirect(req.getHeader("Referer"));
}
}提交地址的修改
<td><a class="deleteItem" href="cartServlet?action=deleteItem&id=${entry.value.id}">删除</a></td>确认删除功能的实现
<script type="text/javascript">
$(function () {
$("a.deleteItem").click(function () {
return confirm("确认要删除【" + $(this).parent().parent().find("td:first").text()+ "】吗？")
});
});
</script>9、清空购物车功能的实现
编写clear方法
protected void clear(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// 获取购物车对象
Cart cart = (Cart) req.getSession().getAttribute("cart");
if (cart != null) {
// 清空购物车
cart.clear();
// 重定向回原来的页面
resp.sendRedirect(req.getHeader("Referer"));
}
}修改提交地址
<span class="cart_span"><a id="clearCart" href="cartServlet?action=clear">清空购物车</a></span>确认清空购物车的提示
$("#clearCart").click(function () {
return confirm("确定要清空购物车吗？");
});10、修改购物车的商品数量
编写update方法
protected void update(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// 获取请求的商品id、数量
int count = WebUtils.parseInt(req.getParameter("count"), 1);
int id = WebUtils.parseInt(req.getParameter("id"), 0);
Cart cart = (Cart) req.getSession().getAttribute("cart");
if(cart != null){
cart.updateCount(id,count);
// 重定向回原来的页面
resp.sendRedirect(req.getHeader("Referer"));
}
}修改提交的表单
<td><input type="text" value="${entry.value.count}" style="width: 80px"
class="updateCount" bookId="${entry.value.id}"></td>确认修改数量的提示
$(".updateCount").change(function () {
var name = $(this).parent().parent().find("td:first").text();//获取商品名称
var id = $(this).attr("bookId");//获取商品id
var count = this.value;//获取商品数量
if(confirm("确定要修改【" + name + "】的数量为：" + count +"吗？")) {
// 确认修改，发起请求
location = "${basePath}cartServlet?action=update&count=" + count + "&id=" + id;
}else {
// 取消修改
this.value = this.defaultValue;
}
});11、购物车添加商品的回显
在添加商品功能中保存商品名称
System.out.println("Referer:" + req.getHeader("Referer"));
req.getSession().setAttribute("lastName",cartItem.getName());
resp.sendRedirect(req.getHeader("Referer"));在首页修改数据的显示
<div style="text-align: center">
<c:if test="${empty sessionScope.cart.items}">
<span></span>
<div>
<span style="color: red">当前购物车为空</span>
</div>
</c:if>
<c:if test="${not empty sessionScope.cart.items}">
<span>您的购物车中有${sessionScope.cart.totalCount}件商品</span>
<div>
您刚刚将<span style="color: red">${sessionScope.lastName}</span>加入到了购物车中
</div>
</c:if>
</div>
注：本文章所含内容来源于尚硅谷教育，仅供学习参考使用。