ShoppingCart.java
package com.aff.bookstore.domain; import java.util.Collection; import java.util.HashMap; import java.util.Map; public class ShoppingCart { private Map<Integer, ShoppingCartItem> books = new HashMap<>(); /** * 修改指定购物项的数量 */ public void updateItemQuantity(Integer id, int quantity){ ShoppingCartItem sci =books.get(id); if(sci != null){ sci.setQuantity(quantity); } } /** * 移除指定的购物项 * @param id */ public void removeItem(Integer id){ books.remove(id); } /** * 清空购物车 */ public void clear(){ books.clear(); } /** * 返回购物车是否为空 * @return */ public boolean isEmpty(){ return books.isEmpty(); } /** * 获取购物车中所有的商品的总的钱数 * @return */ public float getTotalMoney(){ float total = 0; for(ShoppingCartItem sci: getItems()){ total += sci.getItemMoney(); } return total; } /** * 获取购物车中的所有的 ShoppingCartItem 组成的集合 * @return */ public Collection<ShoppingCartItem> getItems(){ return books.values(); } /** * 返回购物车中商品的总数量 * @return */ public int getBookNumber(){ int total = 0; for(ShoppingCartItem sci: books.values()){ total += sci.getQuantity(); } return total; } public Map<Integer, ShoppingCartItem> getBooks() { return books; } /** * 检验购物车中是否有 id 指定的商品 * @param id * @return */ public boolean hasBook(Integer id){ return books.containsKey(id); } /** * 向购物车中添加一件商品 * @param book */ public void addBook(Book book){ //1. 检查购物车中有没有该商品, 若有, 则使其数量 +1, 若没有, //新创建其对应的 ShoppingCartItem, 并把其加入到 books 中 ShoppingCartItem sci = books.get(book.getId()); if(sci == null){ sci = new ShoppingCartItem(book); books.put(book.getId(), sci); }else{ sci.increment(); } } }
ShoppingCartItem.java
package com.aff.bookstore.domain; /** * 封装了购物车中的商品, 包含对商品的引用以及购物车中该商品的数量 * */ public class ShoppingCartItem { private Book book; private int quantity; public ShoppingCartItem(Book book) { this.book = book; this.quantity = 1; } public Book getBook() { return book; } public int getQuantity() { return quantity; } public void setQuantity(int quantity) { this.quantity = quantity; } /** * 返回该商品在购物车中的钱数 * @return */ public float getItemMoney(){ return book.getPrice() * quantity; } /** * 使商品数量 + 1 */ public void increment(){ quantity++; } }
BookStoreWebUtils.java
package com.aff.bookstore.web; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import com.aff.bookstore.domain.ShoppingCart; //从session中获取购物车对象，若session中没有，则创建一个新的购物车对象放入到session中， 若有则直接返回 public class BookStoreWebUtils { public static ShoppingCart getShopingCart(HttpServletRequest request) { HttpSession session = request.getSession(); ShoppingCart sc = (ShoppingCart) session.getAttribute("ShoppingCart"); if (sc==null ) { sc = new ShoppingCart(); session.setAttribute("ShoppingCart", sc); } return sc; } }
cart.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 PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> <script type="text/javascript" src="script/jquery-1.12.3.js"></script> <%@include file="/commons/queryCondition.jsp" %> <script type="text/javascript"> $(function(){ $(".delete").click(function(){ var tr = $(this).parent().parent(); var title =$.trim($tr.find("td:first").text()); var flag = confirm("确定要删除"+title+"的信息吗""); if (flag) { return true; } return false; }); }); </script> </head> <body> <center> <br><br> <div>您的购物差中共有 ${sessionScope.ShoppingCart.bookNumber} 本书</div> <table cellpadding="10"> <tr> <td>Title</td> <td>Quantity</td> <td>Price</td> <td> </td> </tr> <c:forEach items="${sessionScope.ShoppingCart.items }" var="item"> <tr> <td>${item.book.title }</td> <td>${item.quantity }</td> <td>${item.book.price }</td> <td><a href="bookServlet?method=remove&pageNo=${param.pageNo }&id=${item.book.id}" class="delete">删除</a></td> </tr> </c:forEach> <tr> <td colspan="4"> 总金额：￥${sessionScope.ShoppingCart.totalMoney}</td> </tr> <tr> <td colspan="4"> <a href="bookServlet?method=getBooks&pageNo=${param.pageNo }">继续购物</a> <a href="bookServlet?method=clear" >清空购物车</a> <a href="">结账</a> </td> </tr> </table> </center> <br><br> </body> </html>
empty.jsp
<body> <h3>您的购物车为空</h3> <a href="index.jsp">继续购物</a> </body>
BookServlet.java
package com.aff.bookstore.servlet; import java.io.IOException; import java.lang.reflect.Method; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.aff.bookstore.domain.Book; import com.aff.bookstore.domain.ShoppingCart; import com.aff.bookstore.service.BookService; import com.aff.bookstore.web.BookStoreWebUtils; import com.aff.bookstore.web.CriteriaBook; import com.aff.bookstore.web.Page; @WebServlet("/bookServlet") public class BookServlet extends HttpServlet { private static final long serialVersionUID = 1L; protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request, response); } private BookService bookService = new BookService(); protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String methodName = request.getParameter("method"); try { Method method = getClass().getDeclaredMethod(methodName, HttpServletRequest.class, HttpServletResponse.class); method.setAccessible(true); method.invoke(this, request, response); } catch (Exception e) { e.printStackTrace(); } } protected void clear(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { ShoppingCart sc = BookStoreWebUtils.getShopingCart(request); bookService.clearShoppingCart(sc); request.getRequestDispatcher("/WEB-INF/pages/empty.jsp").forward(request, response); } // 删除商品 protected void remove(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String idStr = request.getParameter("id"); int id = -1; try { id = Integer.parseInt(idStr); } catch (Exception e) { } ShoppingCart sc = BookStoreWebUtils.getShopingCart(request); bookService.removeItemFromShoppingCart(sc, id); if (sc.isEmpty()) { request.getRequestDispatcher("/WEB-INF/pages/empty.jsp").forward(request, response); } // 删除完再转发为回来 request.getRequestDispatcher("/WEB-INF/pages/cart.jsp").forward(request, response); } protected void toCartPage(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.getRequestDispatcher("/WEB-INF/pages/cart.jsp").forward(request, response); } protected void addToCart(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // 1.获取商品的id String idStr = request.getParameter("id"); int id = -1; boolean flag = false; try { id = Integer.parseInt(idStr); } catch (Exception e) { } if (id > 0) { // 2.获取购物差对象 ShoppingCart sc = BookStoreWebUtils.getShopingCart(request); // 3.调用 BookService 的addToCart() 方法 把商品放到购物车中 flag = bookService.addToCart(id, sc); } if (flag) { // 4.直接调用 getBooks()方法 getBooks(request, response); return; } response.sendRedirect(request.getContextPath() + "/errror-1.jsp"); } protected void getBook(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String idStr = request.getParameter("id"); int id = -1; Book book = null; try { id = Integer.parseInt(idStr); } catch (NumberFormatException e) { } if (id > 0) { book = bookService.getBook(id); if (book == null) { response.sendRedirect(request.getContextPath() + "/errror-1.jsp"); return; } } request.setAttribute("book", book); request.getRequestDispatcher("/WEB-INF/pages/book.jsp").forward(request, response); } protected void getBooks(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String pageNoStr = request.getParameter("pageNo"); String minPriceStr = request.getParameter("minPrice"); String maxPriceStr = request.getParameter("maxPrice"); int pageNo = 1; int minPrice = 0; int maxPrice = Integer.MAX_VALUE; try { pageNo = Integer.parseInt(pageNoStr); } catch (Exception e) { } try { minPrice = Integer.parseInt(minPriceStr); } catch (Exception e) { } try { maxPrice = Integer.parseInt(maxPriceStr); } catch (Exception e) { } CriteriaBook criteriaBook = new CriteriaBook(minPrice, maxPrice, pageNo); Page<Book> page = bookService.getPage(criteriaBook); request.setAttribute("bookpage", page); request.getRequestDispatcher("/WEB-INF/pages/books.jsp").forward(request, response); } }
解决中文乱码问题
EncodingFilter.java
package com.aff.bookstore.filter; import java.io.IOException; import javax.servlet.Filter; import javax.servlet.FilterChain; import javax.servlet.FilterConfig; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.annotation.WebFilter; @WebFilter("/*") public class EncodingFilter implements Filter { public EncodingFilter() { } public void destroy() { } public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { String encoding = filterConfig.getServletContext().getInitParameter("encoding"); request.setCharacterEncoding(encoding); chain.doFilter(request, response); } private FilterConfig filterConfig = null; public void init(FilterConfig fConfig) throws ServletException { this.filterConfig = fConfig; } }
web.xml
<context-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </context-param>
目录
