handlerequest.java

Ajax开发精要——概念、案例与框架.很适合初学者学习。

package com.ajaxlab.ajax;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.*;

public class HandleRequest extends HttpServlet {
	private static final long serialVersionUID = -7289744742462744450L;
	public void service (HttpServletRequest request, HttpServletResponse response)throws IOException, ServletException {
		String action = request.getParameter("action");
		System.out.println("操作类别："+action);
		if("showProduct".equalsIgnoreCase(action)) 
			this.showProduct(request, response);
		else if("addProduct".equalsIgnoreCase(action))
			this.addProduct(request, response);
		else if("deleteProduct".equalsIgnoreCase(action))
			this.deleteProduct(request, response);
		else if("adjustProduct".equalsIgnoreCase(action))
			this.adjustProduct(request, response);
		else if("viewShoppingCar".equalsIgnoreCase(action))
			this.viewShoppingCar(request, response);
	}
	/**
	 * 获取MP3播放器的信息
	 * @param request
	 * @param response
	 * @throws IOException
	 * @throws ServletException
	 */
	public void showProduct(HttpServletRequest request, HttpServletResponse response)throws IOException, ServletException {
		PrintWriter out = response.getWriter();
		String productName = ExtendString.formDecode(request.getParameter("productName"));
		response.setContentType("application/xml");
		MP3PlayerService service = new MP3PlayerService();
		try {
			service.outputProductInfo(out, productName);
		}catch(Exception ex) {
			
		}
	}
	/**
	 * 添加MP3播放器到购物车中
	 * @param request
	 * @param response
	 * @throws IOException
	 * @throws ServletException
	 */
	public void addProduct(HttpServletRequest request, HttpServletResponse response) 
		throws IOException, ServletException {
		PrintWriter out = response.getWriter();
		String productName = ExtendString.formDecode(request.getParameter("productName"));
		HttpSession session = request.getSession();
		MP3PlayerService service = new MP3PlayerService();
		Map products = (HashMap)session.getAttribute("products");
		if(products==null) products = new HashMap();
		if(products.get(productName)!=null) {
			ProductOrdered po = 
				(ProductOrdered)products.get(productName);
			po.setCount(po.getCount() + 1);
			products.put(po.getProductName(),po);
		}
		else {
			MP3Player mp3Player = service.getMP3Player(productName);
			if(mp3Player!=null) {
				ProductOrdered po = new ProductOrdered();
				po.setProductName(mp3Player.getProductName());
				po.setCount(1);
				po.setPrice(mp3Player.getPrice());
				products.put(po.getProductName(),po);
			}
		}
		session.setAttribute("products",products);
		response.setContentType("application/xml");
		try {
			service.outputCar(out, products);
		}catch(Exception ex) {
		}
	}
	/**
	 * 从购物车中删除MP3播放器
	 * @param request
	 * @param response
	 * @throws IOException
	 * @throws ServletException
	 */
	public void deleteProduct(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
		PrintWriter out = response.getWriter();
		String productName = ExtendString.formDecode(request.getParameter("productName"));
		HttpSession session = request.getSession();
		MP3PlayerService service = new MP3PlayerService();
		Map products = (HashMap)session.getAttribute("products");
		if(products==null) products = new HashMap();
		else {
			products.remove(productName);
		}
		session.setAttribute("products",products);
		response.setContentType("application/xml");
		try {
			service.outputCar(out, products);
		}catch(Exception ex) {
			
		}
	}
	/**
	 * 调整购物车中的MP3播放器
	 * @param request
	 * @param response
	 * @throws IOException
	 * @throws ServletException
	 */
	public void adjustProduct(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
		PrintWriter out = response.getWriter();
		String productName = ExtendString.formDecode(request.getParameter("productName"));
		String count = ExtendString.formDecode(request.getParameter("count"));
		HttpSession session = request.getSession();
		MP3PlayerService service = new MP3PlayerService();
		Map products = (HashMap)session.getAttribute("products");
		if(products==null) products = new HashMap();
		else {
			ProductOrdered po = (ProductOrdered)products.get(productName);
			po.setCount(Integer.parseInt(count));
			products.put(po.getProductName(),po);
		}
		session.setAttribute("products",products);
		response.setContentType("application/xml");
		try {
			service.outputCar(out, products);
		}catch(Exception ex) {
			
		}
	}
	/**
	 * 查看购物车
	 * @param request
	 * @param response
	 * @throws IOException
	 * @throws ServletException
	 */
	public void viewShoppingCar(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
		PrintWriter out = response.getWriter();
		HttpSession session = request.getSession();
		MP3PlayerService service = new MP3PlayerService();
		Map products = (HashMap)session.getAttribute("products");
		if(products==null) products = new HashMap();
		response.setContentType("application/xml");
		try {
			service.outputCar(out, products);
		}catch(Exception ex) {
			
		}
	}
}