javaweb图书商城 javaweb图书商城设计之图书模块(4)
Android-Dev 人气:0想了解javaweb图书商城设计之图书模块(4)的相关内容吗,Android-Dev在本文为您仔细讲解javaweb图书商城的相关知识和一些Code实例,欢迎阅读和指正,我们先划重点:javaweb,图书商城,图书模块,下面大家一起来学习吧。
本文接着上一篇图书商城分类模块进行学习,供大家参考,具体内容如下
1、创建相关类
cn.itcast.bookstore.book
domain:Book
dao:BookDao
service :BookService
web.servle:BookServlet
Book
public class Book { private String bid; private String bname; private double price; private String author; private String image; private Category category; private boolean del; }
BookDao
public class BookDao { private QueryRunner qr = new TxQueryRunner(); /** * 查询所有图书 * @return */ public List<Book> findAll() { try { String sql = "select * from book where del=false"; return qr.query(sql, new BeanListHandler<Book>(Book.class)); } catch(SQLException e) { throw new RuntimeException(e); } } /** * 按分类查询 * @param cid * @return */ public List<Book> findByCategory(String cid) { try { String sql = "select * from book where cid=? and del=false"; return qr.query(sql, new BeanListHandler<Book>(Book.class), cid); } catch(SQLException e) { throw new RuntimeException(e); } } /** * 加载方法 * @param bid * @return */ public Book findByBid(String bid) { try { /* * 我们需要在Book对象中保存Category的信息 */ String sql = "select * from book where bid=?"; Map<String,Object> map = qr.query(sql, new MapHandler(), bid); /* * 使用一个Map,映射出两个对象,再给这两个对象建立关系! */ Category category = CommonUtils.toBean(map, Category.class); Book book = CommonUtils.toBean(map, Book.class); book.setCategory(category); return book; } catch(SQLException e) { throw new RuntimeException(e); } } /** * 查询指定分类下的图书本数 * @param cid * @return */ public int getCountByCid(String cid) { try { String sql = "select count(*) from book where cid=?"; Number cnt = (Number)qr.query(sql, new ScalarHandler(), cid); return cnt.intValue(); } catch(SQLException e) { throw new RuntimeException(e); } } /** * 添加图书 * @param book */ public void add(Book book) { try { String sql = "insert into book values(?,?,?,?,?,?)"; Object[] params = {book.getBid(), book.getBname(), book.getPrice(), book.getAuthor(), book.getImage(), book.getCategory().getCid()}; qr.update(sql, params); } catch(SQLException e) { throw new RuntimeException(e); } } /** * 删除图书 * @param bid */ public void delete(String bid) { try { String sql = "update book set del=true where bid=?"; qr.update(sql, bid); } catch(SQLException e) { throw new RuntimeException(e); } } public void edit(Book book) { try { String sql = "update book set bname=?, price=?,author=?, image=?, cid=? where bid=?"; Object[] params = {book.getBname(), book.getPrice(), book.getAuthor(), book.getImage(), book.getCategory().getCid(), book.getBid()}; qr.update(sql, params); } catch(SQLException e) { throw new RuntimeException(e); } } }
BookService
public class BookService { private BookDao bookDao = new BookDao(); /** * 查询所有图书 * @return */ public List<Book> findAll() { return bookDao.findAll(); } /** * 按分类查询图书 * @param cid * @return */ public List<Book> findByCategory(String cid) { return bookDao.findByCategory(cid); } public Book load(String bid) { return bookDao.findByBid(bid); } /** * 添加图书 * @param book */ public void add(Book book) { bookDao.add(book); } public void delete(String bid) { bookDao.delete(bid); } public void edit(Book book) { bookDao.edit(book); } }
BookServlet
public class BookServlet extends BaseServlet { private BookService bookService = new BookService(); public String load(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { /* * 1. 得到参数bid * 2. 查询得到Book * 3. 保存,转发到desc.jsp */ request.setAttribute("book", bookService.load(request.getParameter("bid"))); return "f:/jsps/book/desc.jsp"; } /** * 查询所有图书 * @param request * @param response * @return * @throws ServletException * @throws IOException */ public String findAll(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setAttribute("bookList", bookService.findAll()); return "f:/jsps/book/list.jsp"; } /** * 按分类查询 * @param request * @param response * @return * @throws ServletException * @throws IOException */ public String findByCategory(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String cid = request.getParameter("cid"); request.setAttribute("bookList", bookService.findByCategory(cid)); return "f:/jsps/book/list.jsp"; } }
2、查询所有图书
流程:left.jsp(全部分类) -> BookServlet#findAll() -> /jsps/book/list.jsp
3、按分类查询图书
流程:left.jsp -> BookServlet#findByCategory() -> list.jsp
4、查询详细信息(加载)
流程:list.jsp(点击某一本书) -> BookServlet#load() -> desc.jsp
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持。
加载全部内容