JavaWeb專案練習--分類模組、圖書模組
阿新 • • 發佈：2018-11-03
分類模組
1 分類模組的相關類建立
ywnxbx.bookstore.category
domain：Category
dao：CategoryDao
service：CategoryService
web.servlet：CategoryServlet
2 查詢所有分類
流程：main.jsp（< iframe >） --> CategoryService#findAll() --> left.jsp
domain:
public class Category { private String cid; private String cname; }
dao:
public class CategoryDao { private QueryRunner qr = new TxQueryRunner(); /** * 查詢所有分類 * @return */ public List<Category> findAllCategory() { String sql = "select * from category"; try { return qr.query(sql, new BeanListHandler<Category>(Category.class)); } catch (SQLException e) { throw new RuntimeException(e); } } /** * 新增分類 * @param category */ public void addCategory(Category category) { String sql = "insert into category values(?,?)"; try { qr.update(sql,category.getCid(),category.getCname()); } catch (SQLException e) { throw new RuntimeException(e); } } /** * 刪除分類 * @param cid */ public void deleteCategory(String cid) { String sql = "delete from category where cid = ?"; try { qr.update(sql,cid); } catch (SQLException e) { throw new RuntimeException(e); } } /** * 載入分類 * @param cid * @return */ public Category load(String cid) { String sql = "select * from category where cid = ?"; try { return qr.query(sql, new BeanHandler<Category>(Category.class),cid); } catch (SQLException e) { throw new RuntimeException(e); } } /** * 修改分類名稱 * @param category */ public void edit(Category category) { String sql = "update category set cname = ? where cid = ?"; try { qr.update(sql,category.getCname(),category.getCid()); } catch (SQLException e) { throw new RuntimeException(e); } } }
service:
public class CategoryService { private CategoryDao categoryDao = new CategoryDao(); private BookDao bookDao = new BookDao(); /** * 查詢所有分類 * @return */ public List<Category> findAllCategory() { return categoryDao.findAllCategory(); } /** * 新增分類 * @param category */ public void addCategory(Category category) { categoryDao.addCategory(category); } /** * 刪除分類 * @param string * @throws CategoryException */ public void deleteCategory(String cid) throws CategoryException { /* * 檢查此分類下是否含有圖書 * 若有：不能刪除此分類,丟擲異常 * 呼叫方法刪除 */ int count = bookDao.getCountByCid(cid); if(count > 0) throw new CategoryException("該分類下還有圖書，不能刪除"); categoryDao.deleteCategory(cid); } /** * 載入分類 * @param cid * @return */ public Category load(String cid) { return categoryDao.load(cid); } /** * 修改分類 * @param category */ public void edit(Category category) { categoryDao.edit(category); } }
web.servlet
public class CategoryServlet extends BaseServlet {
private static final long serialVersionUID = 3352017120523237513L;
private CategoryService categoryService = new CategoryService();
/**
* 查詢所有分類
* @param request
* @param response
* @return
* @throws ServletException
* @throws IOException
*/
public String findAllCategory(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//向request域中儲存CategoryList
request.setAttribute("categoryList", categoryService.findAllCategory());
return "f:/jsps/left.jsp";
}
}
圖書模組
1 建立相關類
ywnxbx.bookstore.book
domain：Book
dao：BookDao
service :BookService
web.servle：BookServlet
2 查詢所有圖書
流程：left.jsp（全部分類） BookServlet#findAll() /jsps/book/list.jsp
3 按分類查詢圖書
流程：left.jsp BookServlet#findByCategory() list.jsp
4 查詢詳細資訊（載入）
流程：list.jsp（點選某一本書） BookServlet#load() desc.jsp
domain
public class Book {
private String bid;
private String bname;
private double price;
private String author;
private String image;
private Category category; //多方（書）關聯一方（分類編號）
private boolean del;
}
dao
public class BookDao {
private QueryRunner qr = new TxQueryRunner();
/**
* 查詢所有圖書
* @return
*/
public List<Book> findAllBook(){
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);
}
}
/**
* 按類別編號查詢
* @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);
}
}
/**
* 載入指定圖書
* @param bid
* @return
*/
public Book findByBid(String bid) {
try {
String sql = "select * from book where bid = ?";
/*
* 資料庫表中cid無法與Book中Category完成對映，導致不能查詢到cid
*
* 解決:
* 1.使用map做結果集 目的：將所有查詢結果用鍵值對的方式儲存
* 2.分別用map映射出Category和Book物件
* 3.將Category設定進Book中
*/
Map<String,Object> map = qr.query(sql,new MapHandler(),bid);
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);
}
}
/**
* 查詢指定分類下圖書數目
* @param cid
* @return
*/
public int getCountByCid(String cid) {
try {
String sql = "select count(*) from book where cid = ?";
Number count = (Number) qr.query(sql,new ScalarHandler(),cid);
return count.intValue();
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
/**
* 新增圖書
* @param book
*/
public void add(Book book) {
try {
String sql = "insert into book values(?,?,?,?,?,?,false)";
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);
}
}
/**
* 刪除圖書
* @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);
}
}
/**
* 編輯圖書
* @param book
*/
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);
}
}
}
service
public class BookService {
private BookDao bookDao = new BookDao();
/**
* 查詢所有圖書
* @return
*/
public List<Book> findAllBook(){
return bookDao.findAllBook();
}
/**
* 按類別查詢圖書
* @param cid
* @return
*/
public List<Book> findByCategory(String cid) {
return bookDao.findByCategory(cid);
}
/**
* 載入指定圖書
* @param bid
* @return
*/
public Book load(String bid) {
return bookDao.findByBid(bid);
}
/**
* 新增圖書
* @param book
*/
public void add(Book book) {
bookDao.add(book);
}
/**
* 刪除圖書
* @param bid
*/
public void delete(String bid){
bookDao.delete(bid);
}
/**
* 編輯圖書
* @param book
*/
public void edit(Book book) {
bookDao.edit(book);
}
}
servlet
public class BookServlet extends BaseServlet {
private static final long serialVersionUID = 1L;
private BookService bookService = new BookService();
/**
* 查詢所有圖書
* @param request
* @param response
* @return
* @throws ServletException
* @throws IOException
*/
public String findAllBook(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//查詢所有圖書，將查詢結果儲存到request中
request.setAttribute("bookList", bookService.findAllBook());
return "f:/jsps/book/list.jsp";
}
/**
* 按分類查詢圖書
* @param request
* @param response
* @return
* @throws ServletException
* @throws IOException
*/
public String findByCategory(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//得到類別編號
String cid = request.getParameter("cid");
//按分類查詢圖書，將查詢結果儲存到request中
request.setAttribute("bookList", bookService.findByCategory(cid));
return "f:/jsps/book/list.jsp";
}
/**
* 載入指定圖書
* @param request
* @param response
* @return
* @throws ServletException
* @throws IOException
*/
public String load(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//得到圖書bid
String bid = request.getParameter("bid");
//通過bid查詢，將結果儲存到request中
request.setAttribute("book", bookService.load(bid));
return "f:/jsps/book/desc.jsp";
}
}
jsps:
1）desc.jsp 顯示圖書資訊
<style type="text/css">
body {
font-size: 10pt;
}
div {
margin:20px;
border: solid 2px gray;
width: 150px;
height: 150px;
text-align: center;
}
li {
margin: 10px;
}
a {
background: url(<c:url value='/images/all.png'/>) no-repeat;
display: inline-block;
background-position: 0 -70px;
margin-left: 30px;
height: 36px;
width: 146px;
}
a:HOVER {
background: url(<c:url value='/images/all.png'/>) no-repeat;
display: inline-block;
background-position: 0 -106px;
margin-left: 30px;
height: 36px;
width: 146px;
}
</style>
</head>
<body>
<div>
<img src="<c:url value='/${book.image }'/>" border="0"/>
</div>
<ul>
<li>書名：${book.bname }</li>
<li>作者：${book.author }</li>
<li>單價：${book.price }</li>
</ul>
<form id="form" action="<c:url value='/CartServlet'/>" method="post">
<%--指定要呼叫的方法 --%>
<input type="hidden" name="method" value="add"/>
<input type="hidden" name="bid" value="${book.bid }"/>
<input type="text" size="3" name="count" value="1"/>
</form>
<a href="javascript:document.getElementById('form').submit();"></a>
</body>
2)list.jsp 遍歷顯示所有圖書
<style type="text/css">
body {
font-size: 10pt;
}
.icon {
margin:10px;
border: solid 2px gray;
width: 160px;
height: 180px;
text-align: center;
float: left;
}
</style>
</head>
<body>
<c:forEach items="${bookList }" var="book">
<div class="icon">
<a href="<c:url value='/BookServlet?method=load&bid=${book.bid }'/>">
<img src="<c:url value='/${book.image }'/>" border="0"/></a> <br/>
<a href="<c:url value='/BookServlet?method=load&bid=${book.bid }'/>">${book.bname }</a>
</div>
</c:forEach>
</body>