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基于Servlet Controller的Model2

示例

这个应用程序可以用来输入产品信息；在如图的表单中输入信息：

http://localhost:8080/base-webapp/product_input

并提交，然后，应用程序给用户发送一个确认页面，并显示所保存产品的详细信息。

http://localhost:8080/base-webapp/product_save

这个应用程序能够执行下面这两个action：

• 显示Add Product表单，URI中包含字符串“product_input”
• 保存产品，并返回确认页面，URI中包含字符串“product_save”

这个应用包含一下组件：

• Product类时模型对象，包含产品信息
• ProductForm类，封装用于输入产品的HTML表单域
• ControllerServlet类，是这个Model2应用的Controller
• Action类，用于保存产品信息
• View的两个JSP页面：ProductForm.jsp和ProductDetails.jsp

源码：

product bean 类：

package com.gof.test.bean;import java.io.Serializable;public class Product implements Serializable {	/**	 * 	 */	private static final long serialVersionUID = -2088880133830936693L;	private String nameString;	private String description;	private float price;		public String getName(){		return nameString;	}	public void setName(String name){		this.nameString = name;	}	public String getDescription(){		return description;	}	public void setDescription(String description){		this.description = description;	}	public float getPrice(){		return price;	}	public void setPrice(float price){		this.price = price;	}}

product form 类：

package com.gof.test.bean;public class ProductForm {	private String nameString;	private String description;	private String price;		public String getName(){		return nameString;	}	public void setName(String name){		this.nameString = name;	}	public String getDescription(){		return description;	}	public void setDescription(String description){		this.description = description;	}	public String getPrice(){		return price;	}	public void setPrice(String price){		this.price = price;	}}

ControllerServlet类：

package com.gof.test.servlet;import java.io.IOException;import java.net.URL;import javax.print.DocFlavor.STRING;import javax.servlet.RequestDispatcher;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.gof.test.action.SaveProductAction;import com.gof.test.bean.Product;import com.gof.test.bean.ProductForm;public class ControllerServlet extends HttpServlet {		protected void doGet(HttpServletRequest req, HttpServletResponse resp)			throws ServletException, IOException{		process(req, resp);	}		protected void doPost(HttpServletRequest req, HttpServletResponse resp)			throws ServletException, IOException{		process(req, resp);	}		private void process(HttpServletRequest req, HttpServletResponse resp)			throws ServletException, IOException{		String uri = req.getRequestURI();		int lastIndex = uri.lastIndexOf("/");		String action = uri.substring(lastIndex + 1);		String dispatchUrlString = null;				if (action.equals("product_input")){			dispatchUrlString = "/jsp/controller/ProductForm.jsp";		}else 		if (action.equals("product_save")){			ProductForm productForm = new ProductForm();						productForm.setName(req.getParameter("name"));			productForm.setDescription(req.getParameter("description"));			productForm.setPrice(req.getParameter("price"));						Product product = new Product();			product.setName(productForm.getName());			product.setDescription(productForm.getDescription());			try{				product.setPrice(Float.parseFloat(productForm.getPrice()));			}catch (NumberFormatException e){				e.printStackTrace();			}						SaveProductAction saveProductAction = new SaveProductAction();			saveProductAction.save(product);						req.setAttribute("product", product);			dispatchUrlString = "/jsp/controller/ProductDetails.jsp";		}        		if (dispatchUrlString != null){			RequestDispatcher rDispatcher = req.getRequestDispatcher(dispatchUrlString);			rDispatcher.forward(req, resp);		}	}}

在web.xml中注册这个servlet：

     
     	 
    
     controller
      	 
    
     com.gof.test.servlet.ControllerServlet
       
      
         
    
     controller
          
    
     /product_input
       
      
         
    
     controller
          
    
     /product_save
       
   

save action类：

package com.gof.test.action;import com.gof.test.bean.Product;public class SaveProductAction {    public void save(Product product){    	// insert product into the database    }}

View - ProductForm.jsp :

<%@ page language="java" contentType="text/html; charset=utf-8"    pageEncoding="utf-8"%>
   
   
    
    
Add a product
    
    
        
     
                  
       
                        
Product Name:
                        
                   
                   
                        
Description:
                        
                   
                   
                        
Price:
                        
                   
                   
                        
                        
                   
              
     
    
    
   

View - ProductDeails.jsp：

<%@ page language="java" contentType="text/html; charset=utf-8"    pageEncoding="utf-8"%>
   
   
    
    
The product has been saved.
    
    
        
    
Details:
        Product Name: ${product.name}
    
        Description: ${product.description}
    
        Price:${product.price}