每日总结2023-05-19

package servlets;

import java.io.IOException;
import java.util.*;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.json.*;

import book.bean.Book;

/**
 * 接受客户端后缀为action的请求，并进行处理，并返回响应
 * 
 * @author Leiyu
 * @version 1.0
 *
 */
@WebServlet("*.action")
public class AjaxController extends HttpServlet {
    private static final long serialVersionUID = 1L;

    public AjaxController() {
        super();
        // TODO Auto-generated constructor stub
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doPost(request, response);
    }

    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");

        String actionUrl = request.getServletPath(); // 获取客户端的访问URL地址信息
        
        if (actionUrl.equals("/list.action")) { // 查询所有图书
            ArrayList<Book> list = Book.getBookList(); // 调用BookInfo的getBookList方法完成
            // 使用JSONArray对象将结果构建为json对象并输出到客户端
            JSONArray jsonArray = new JSONArray();
            for (int i = 0; i < list.size(); i++) {
                Book book = list.get(i);
                Map<String, Object> map = new HashMap<String, Object>();
                map.put("id", book.getId());
                map.put("bookname", book.getBookname());
                map.put("author", book.getAuthor());
                map.put("price", book.getPrice());
                JSONObject BookObj = new JSONObject(map);
                jsonArray.put(BookObj);
            }
            // 向客户端返回json结果
            response.getWriter().print(jsonArray.toString());

        } else if (actionUrl.equals("/add.action")) { // 增加图书操作
            Book bi = new Book();
            bi.setBookname(request.getParameter("bookname"));
            bi.setAuthor(request.getParameter("author"));
            bi.setPrice(request.getParameter("price"));
        
            int r = Book.addBook(bi); // 调用BookInfo的addBook方法完成
            // 向客户端返回结果
            response.getWriter().print(r);

        } else if (actionUrl.equals("/edit.action")) { // 编辑图书操作
            String id = request.getParameter("id");
            Book bi = Book.getBookById(id); // 调用BookInfo的getBookById方法完成
            // 将该对象构建为json数据
            Map<String, Object> map = new HashMap<String, Object>();
            map.put("id", bi.getId());
            map.put("bookname", bi.getBookname());
            map.put("author", bi.getAuthor());
            map.put("price", bi.getPrice());
            JSONObject BookObj = new JSONObject(map);
            // 向客户端返回结果
            response.getWriter().print(BookObj.toString());

        } else if (actionUrl.equals("/update.action")) { // 更新图书操作
            Book bi = new Book();
            bi.setId(request.getParameter("id"));
            bi.setBookname(request.getParameter("bookname"));
            bi.setAuthor(request.getParameter("author"));
            bi.setPrice(request.getParameter("price"));
            int r = Book.updateBook(bi);// 调用BookInfo的updateBook方法完成
            response.getWriter().print(r); // 向客户端返回结果

        } else if (actionUrl.equals("/delete.action")) { // 删除图书操作
            String id = request.getParameter("id");
            int r = Book.deleteBook(id); // 调用BookInfo的deleteBook方法完成
            response.getWriter().print(r); // 向客户端返回结果
        }
    }

}

使用Ajax来进行操作