showbook.java

书店实现用struts实现的一个系统 采用mysql数据库

/**
 * 该Servlet接受来自index.jsp中图书导航链接及站内搜索的请求， 
 * 用于判断需显示图书并从数据库中读出对应图书信息，
 * 最后将控制权交给index.jsp
 */

import java.io.*;
import java.sql.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import bean.BookInf;
import bean.DBClass;
import bean.StrClass;

public class ShowBook extends HttpServlet{
	public void doGet(HttpServletRequest request, HttpServletResponse response)
	throws ServletException, IOException{
		request.setCharacterEncoding("gb2312");
		String key=request.getParameter("key");  //key变量用于储存用户搜索信息
		String message="";
		Vector booklist=new Vector();  //booklist变量用于显示待显示图书的信息
		HttpSession session=request.getSession();
		String query="SELECT * FROM book WHERE ";  //query变量用于储存SQL语句
		
		/* 移除session中已有booklist变量 */
		if(session.getAttribute("boolist")!=null){
			session.removeAttribute("boolist");
		}
		
		/* 判断哪些图书需要被显示 */
		if(key==null){    //用户没有进行站内搜索
			if(request.getParameter("type")==null){  
				query+="ifNew='yes'";
			} else {
				String type="";
				if(request.getParameter("type").equals("computer")){
					type="计算机";
				}
				if(request.getParameter("type").equals("electron")){
					type="电子";
				}
				if(request.getParameter("type").equals("communication")){
					type="通信";
				}
				if(request.getParameter("type").equals("biology")){
					type="生物";
				}
				if(request.getParameter("type").equals("iatrology")){
					type="医学";
				}
				if(request.getParameter("type").equals("geography")){
					type="地理";
				}
				if(request.getParameter("type").equals("astronomy")){
					type="天文";
				}
				if(request.getParameter("type").equals("machine")){
					type="机械";
				}
				if(request.getParameter("type").equals("chemistry")){
					type="化学";
				}
				if(request.getParameter("type").equals("physics")){
					type="物理";
				}
				if(request.getParameter("type").equals("maths")){
					type="数学";
				}
				if(request.getParameter("type").equals("literature")){
					type="文学";
				}
				if(request.getParameter("type").equals("art")){
					type="美术";
				}
				if(request.getParameter("type").equals("music")){
					type="音乐";
				}
				if(request.getParameter("type").equals("photography")){
					type="摄影";
				}
				if(request.getParameter("type").equals("sculpture")){
					type="雕塑";
				}
				if(request.getParameter("type").equals("modernart")){
					type="现代艺术";
				}
				if(request.getParameter("type").equals("folkart")){
					type="中国民间艺术";
				}
				if(request.getParameter("type").equals("dress")){
					type="时装";
				}
				if(request.getParameter("type").equals("sociality")){
					type="社交";
				}
				if(request.getParameter("type").equals("cook")){
					type="烹饪";
				}
				if(request.getParameter("type").equals("home")){
					type="家居";
				}
				if(request.getParameter("type").equals("car")){
					type="汽车";
				}
				if(request.getParameter("type").equals("health")){
					type="保健";
				}
				if(request.getParameter("type").equals("health")){
					type="宠物";
				}
				if(request.getParameter("type").equals("economy")){
					type="经济";
				}
				if(request.getParameter("type").equals("law")){
					type="法律";
				}
				if(request.getParameter("type").equals("politics")){
					type="政治";
				}
				if(request.getParameter("type").equals("philosophy")){
					type="哲学";
				}
				if(request.getParameter("type").equals("history")){
					type="历史";
				}
				if(request.getParameter("type").equals("military")){
					type="军事";
				}
				if(request.getParameter("type").equals("religion")){
					type="宗教";
				}
				if(request.getParameter("type").equals("fashion")){
					type="时尚";
				}
				if(request.getParameter("type").equals("film")){
					type="影视";
				}
				if(request.getParameter("type").equals("cartoon")){
					type="动漫";
				}
				if(request.getParameter("type").equals("travel")){
					type="旅游";
				}
				if(request.getParameter("type").equals("sport")){
					type="运动";
				}
				if(request.getParameter("type").equals("science")){
					type="科幻";
				}
				if(request.getParameter("type").equals("fight")){
					type="武侠";
				}
				if(request.getParameter("type").equals("chess")){
					type="棋牌";
				}
				if(request.getParameter("type").equals("baby")){
					type="幼儿启蒙";
				}
				if(request.getParameter("type").equals("teaching")){
					type="中小学教材";
				}
				if(request.getParameter("type").equals("reference")){
					type="教学参考书";
				}
				if(request.getParameter("type").equals("reading")){
					type="课外读物";
				}
				if(request.getParameter("type").equals("copybook")){
					type="字帖";
				}
				if(request.getParameter("type").equals("picture")){
					type="画册";
				}
				if(request.getParameter("type").equals("comity")){
					type="礼仪";
				}
				query+="type="+"\'"+ type + "\'";
			}
		} else {      //请求来自用户搜索
			query+="name LIKE " + "\'%"+ key+ "%\'"
					                   + " OR author LIKE " + "\'%"+ key + "%\'"
					                   + " OR publisher LIKE " + "\'%"+ key+ "%\'";
		} 
		
		/* 数据库操作 */
		DBClass db=new DBClass();   
		db.connect();   
		ResultSet resultset=db.executeQuery(query);
		try{
			while(resultset.next()){
				BookInf book=new BookInf(resultset.getString("id"),
				                         resultset.getString("name"),
				                         resultset.getString("author"),
				                         resultset.getString("publisher"),
				                         resultset.getString("price"),
				                         resultset.getString("type"));
				booklist.addElement(book);
			}
		}catch(SQLException sqle){
			message="executeUpdate:"+sqle;
		}
		db.closeConnection();
		
		/* 将booklist写入session并转到index.jsp */
		session.setAttribute("booklist", booklist);
		response.sendRedirect("/bookshop/index.jsp");
	}
	public void doPost(HttpServletRequest request, HttpServletResponse response) 
	throws ServletException, IOException {
		doGet(request, response);
	}
}