二、实验项目内容（实验题目）
编写代码，掌握MVC的用法。
三、源代码以及执行结果截图：
inputMenu.jsp：
<%@ page contentType="text/html" %>
<%@ page pageEncoding = "utf-8" %>
<jsp:useBean id="menu" class ="save.data.MenuBean" scope="session" />
<style>
#textStyle {
font-family:宋体 ;font-size:36 ;color:blue
}
</style>
<HTML><body bgcolor=#ffccff >
<form action="addMenu" id= textStyle method=post >
输入餐单(每次输入一个消费项目)：<br>
名称：<input type=text name='foodName' id =textStyle value =' 剁椒鱼头 ' size = 8 />
价格：<input type=text name='price' id =textStyle value ='26.9' size = 8 />
<br><input type=submit id=textStyle value=" 添加到餐单 " >
</form>
</body></HTML>
showMenu.jsp：
<%@ page contentType="text/html" %>
<%@ page pageEncoding = "utf-8" %>
<jsp:useBean id="menu" class ="save.data.MenuBean" scope="session" />
<style>
#tom {
font-family:宋体 ;font-size:26 ;color:blue
}
</style>
<HTML><body bgcolor=pink >
<table border=1 >
<tr><th id=tom >序号</th><th id=tom >食物名称</th><th id=tom >价格</th>
<% request.setCharacterEncoding("utf-8");
String index = request.getParameter("删除");
if (index!=null ){
menu.removeFood(Integer.parseInt(index));
}
for (int i=0;i<menu.size();i++){
out.print("<tr>");
out.print("<td id=tom>"+(i+1)+"</td>");
out.print("<td id=tom>"+menu.getFoodName(i)+"</td>");
out.print("<td id=tom>"+menu.getPrice(i)+"</td>");
out.print("<td ><form action ="+"showMenu.jsp"+" method=post>");
out.print("<input type = hidden name = 删除 value = "+i+" />");
out.print("<input type = submit value = 删除该食物 />");
out.print("</form></td>");
out.print("</tr>");
}
%> </table>
<p id = tom >
餐单总额(共有<%=menu.size()%>道食物):
<jsp:getProperty name="menu" property="totalPrice" /><br>
点餐时间:
<jsp:getProperty name="menu" property="time" /></p>
<a id =tom href="inputMenu.jsp" >继续点餐</a>
</body></HTML>
web.xml：
<?xml version="1.0" encoding="utf-8" ?>
<web-app>
<!-- 以下是web.xml文件新添加的内容 -->
<servlet>
<servlet-name>addMenu</servlet-name>
<servlet-class>handle.data.HandleMenu_Servlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>addMenu</servlet-name>
<url-pattern>/addMenu</url-pattern>
</servlet-mapping>
</web-app>
Food：
package save.data;
public class Food implements Comparable<Food>{
String foodName ;
double price;
public void setFoodName(String name){
foodName = name;
}
public String getFoodName(){
return foodName;
}
public void setPrice(double d){
price = d;
}
public double getPrice(){
return price;
}
public int compareTo(Food food){
return (int )(food.getPrice()*1000-price*1000);
}
}
MenuBean：
package save.data;
import java.util.ArrayList;
import java.util.Collections;
public class MenuBean {
String time ;
String totalPrice;
ArrayList<Food> foodList;
public MenuBean(){
foodList = new ArrayList<Food>();
}
public void addFood(Food food){
foodList.add(food);
Collections.sort(foodList);
}
public void removeFood(int index){
if (index>=0){
foodList.remove(index);
Collections.sort(foodList);
}
}
public String getFoodName(int index) {
return foodList.get(index).getFoodName();
}
public double getPrice(int index) {
return foodList.get(index).getPrice();
}
public int size() {
return foodList.size();
}
public void setTime(String time){
this .time = time;
}
public String getTime(){
return time;
}
public String getTotalPrice(){
double sum = 0;
for (Food food:foodList){
sum += food.getPrice();
}
totalPrice = String.format("%.2f",sum);
return totalPrice;
}
}
HandleMenu_Servlet：
package handle.data;
import save.data.Food;
import save.data.MenuBean;
import ++java.util++.*;
import java.io.*;
import java.time.LocalTime;
import javax.servlet.*;
import javax.servlet.http.*;
public class ++HandleMenu_Servlet++ extends HttpServlet{
public void init(ServletConfig config) throws ServletException{
super .init(config);
}
public void service(HttpServletRequest request,HttpServletResponse response)
throws ServletException,IOException{
request.setCharacterEncoding("utf-8");
MenuBean menu = null ;
HttpSession session=request.getSession(true );
menu = (MenuBean)session.getAttribute("menu");
if (menu == null ){
menu = new MenuBean();
session.setAttribute("menu",menu);
}
String foodName = request.getParameter("foodName");
String price = request.getParameter("price");
Food food = new Food();
if (foodName.length()==0||price.length()==0){
response.sendRedirect("inputMenu.jsp");
return ;
}
food.setFoodName(foodName);
food.setPrice(Double.parseDouble(price));
LocalTime dateTime = LocalTime.now();
String str = dateTime.toString();
String time =str.substring(0,str.lastIndexOf("."));
menu.setTime(time);
menu.addFood(food);
response.sendRedirect("showMenu.jsp");
}
}
运行结果图：
点餐：
增加菜单：
删除：
