deletebook.java

使用servlet写的简单网上书店

package c;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
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 javax.sql.DataSource;

import utils.BookUtil;
import entity.Book;

public class DeleteBook extends HttpServlet {
	private ServletConfig config;
	private DataSource ds;
	private PrintWriter out;
	private ResultSet rs;

	public void init(ServletConfig config) throws ServletException {
		super.init(config);
		this.config = config;
		ServletContext context = config.getServletContext();
		ds = (DataSource) context.getAttribute("DataSource");
	}

	public void service(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		HttpSession session = request.getSession(false);
		String pageInfo = "../login.html";
		if(null==session){
		response.sendRedirect(pageInfo);
		}else{
		String str = (String) session.getAttribute("login");
		if ("success".equals(str)) {
			out = response.getWriter();
			this.displayInfo(request,response);

			out.close();
		} else {
			pageInfo = "../login.html";
			response.sendRedirect(pageInfo);
		}
		}
	}

	private void displayInfo(HttpServletRequest req,HttpServletResponse res) {
		Connection con=null;
		try {
			con = ds.getConnection();
			BookUtil bookUtil=new BookUtil(con);
			
			String[] books=req.getParameterValues("books");

			bookUtil.deleteBook(books);
			
			res.sendRedirect("../servlet/BookList");
		} catch (Exception e) {
			e.printStackTrace();
		} finally{
			if(con!=null){
				try {
					con.close();
				} catch (SQLException e) {
					e.printStackTrace();
				}
			}
		}
	}

	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
	}
}