select.java

网上购书系统 采用jsp+servlet+sql2000

package servlet;

import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import base.DaoBase;
import bean.Book;



public class Select extends HttpServlet {

	@Override
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		String tiaojian=request.getParameter("tiaojian");
		tiaojian=new String(tiaojian.getBytes("iso-8859-1"),"gbk");
		String lei=request.getParameter("select");
		lei=new String(lei.getBytes("iso-8859-1"),"gbk");
		DaoBase db=new DaoBase();
		Connection con=db.getConn();
		ArrayList arraylist=new ArrayList();
		int flag=0;
		String sql="select * from book where "+lei+" like'%"+tiaojian+"%'";
		try{
			PreparedStatement ps=con.prepareStatement(sql);
			ResultSet rest=ps.executeQuery();
			 while (rest.next()) 
			 {

				 	flag=1;
					Book book=new Book();
					
					book.setId(rest.getInt(1));
					book.setBookname(rest.getString(2));
					book.setAuthor(rest.getString(3));
					book.setPublish(rest.getString(4));
					book.setBooknum(rest.getString(5));
					book.setContext(rest.getString(6));
					book.setPrice(rest.getFloat(7));
					book.setAmount(rest.getInt(8));
					arraylist.add(book);
				
			}
			if(flag==1){
				request.setAttribute("books", arraylist);
				request.getRequestDispatcher("select.jsp").forward(request,response);
			}
			else {
				request.setAttribute("book", "book");
				request.getRequestDispatcher("view.jsp").forward(request,response);
			}
			rest.close();
			ps.close();
		}catch (Exception e){
		e.printStackTrace();
	}
		db.closeConn();
}
	@Override
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doGet(request,response);
	}

}