一、流程分析
二、代码
1.view层
(1）list.jsp
1 <c:forEach items="${parents }" var="parent"> 2 <tr class="trOneLevel"> 3 <td width="200px;">${parent.cname }</td> 4 <td>${parent.desc }</td> 5 <td width="200px;"> 6 <a href="<c:url value='/admin/AdminCategoryServlet?method=addChildPre&pid=${parent.cid }'/>">添加二级分类</a> 7 <a href="<c:url value='/admin/AdminCategoryServlet?method=editParentPre&cid=${parent.cid }'/>">修改</a> 8 <a onclick="return confirm('您是否真要删除该一级分类？')" href="<c:url value='/admin/AdminCategoryServlet?method=deleteParent&cid=${parent.cid }'/>">删除</a> 9 </td> 10 </tr> 11 <c:forEach items="${parent.children }" var="child"> 12 <tr class="trTwoLevel"> 13 <td>${child.cname }</td> 14 <td>J${child.desc }</td> 15 <td width="200px;" align="right"> 16 <a href="<c:url value='/admin/AdminCategoryServlet?method=editChildPre&cid=${child.cid }'/>">修改</a> 17 <a onclick="return confirm('您是否真要删除该二级分类？')" href="<c:url value='/admin/AdminCategoryServlet?method=deleteChild&cid=${child.cid }'/>">删除</a> 18 </td> 19 </tr> 20 </c:forEach> 21 </c:forEach>
(2)add2.jsp
1 <script type="text/javascript" src="<c:url value='/jquery/jquery-1.5.1.js'/>"></script> 2 <script type="text/javascript"> 3 function checkForm() { 4 if(!$("#cname").val()) { 5 alert("分类名不能为空！"); 6 return false; 7 } 8 if(!$("#pid").val()) { 9 alert("一级分类不能为空！"); 10 return false; 11 } 12 if(!$("#desc").val()) { 13 alert("分类描述不能为空！"); 14 return false; 15 } 16 return true; 17 } 18 </script> 19 <style type="text/css"> 20 body {background: rgb(254,238,189);} 21 </style> 22 </head> 23 24 <body> 25 <h3>添加2级分类</h3> 26 <h1></h1> 27 <p style="font-weight: 900; color: red">${msg }</p> 28 <form action="<c:url value='/admin/AdminCategoryServlet'/>" method="post" onsubmit="return checkForm()"> 29 <input type="hidden" name="method" value='addChild'/> 30 分类名称：<input type="text" name="cname" id="cname"/><br/> 31 一级分类：<select name="pid" id="pid"> 32 <option value="">===选择1级分类===</option> 33 <c:forEach items="${parents }" var="parent"> 34 <option value="${parent.cid }" <c:if test="${parent.cid eq pid }">selected="selected"</c:if>>${parent.cname }</option> 35 </c:forEach> 36 </select><br/> 37 分类描述：<textarea rows="5" cols="50" name="desc" id="desc"></textarea><br/> 38 <input type="submit" value="添加二级分类"/> 39 <input type="button" value="返回" onclick="history.go(-1)"/> 40 </form> 41 </body> 42 </html>
2.servlet层
(1）AdminCategoryServlet.java
1 /** 2 * 准备添加二级分类 3 * @param req 4 * @param resp 5 * @return 6 * @throws ServletException 7 * @throws IOException 8 */ 9 public String addChildPre(HttpServletRequest req, HttpServletResponse resp) 10 throws ServletException, IOException { 11 String pid = req.getParameter("pid"); 12 List<Category> parents = service.findParents(); 13 req.setAttribute("pid", pid); 14 req.setAttribute("parents", parents); 15 return "/adminjsps/admin/category/add2.jsp"; 16 } 17 18 /** 19 * 添加二级 20 * @param req 21 * @param resp 22 * @return 23 * @throws ServletException 24 * @throws IOException 25 */ 26 public String addChild(HttpServletRequest req, HttpServletResponse resp) 27 throws ServletException, IOException { 28 Category child = CommonUtils.toBean(req.getParameterMap(), Category.class); 29 child.setCid(CommonUtils.uuid()); 30 31 Category parent = new Category(); 32 parent.setCid(req.getParameter("pid")); 33 child.setParent(parent); 34 35 service.add(child); 36 return findAll(req, resp); 37 }
3.service层
(1）AdminCategoryService.java
1 /** 2 * 查找所有一级分类 3 * @return 4 */ 5 public List<Category> findParents() { 6 try { 7 return categoryDao.findParents(); 8 } catch (SQLException e) { 9 throw new RuntimeException(e); 10 } 11 } 12 13 /** 14 * 添加分类 15 * @param category 16 */ 17 public void add(Category category) { 18 try { 19 categoryDao.add(category); 20 } catch (SQLException e) { 21 throw new RuntimeException(e); 22 } 23 }
4.dao层
(1）AdminCategroyDao.java
1 /** 2 * 查询所有一级分类 3 * @return 4 * @throws SQLException 5 */ 6 public List<Category> findParents() throws SQLException { 7 // 1. 查询出所有一级分类 8 String sql = "SELECT * FROM t_category WHERE pid IS NULL ORDER BY orderBy"; 9 List<Map<String,Object>> mapList = qr.query(sql, new MapListHandler()); 10 List<Category> parents = toCategoryList(mapList); 11 return parents; 12 } 13 14 /** 15 * 添加分类 16 * @param category 17 * @throws SQLException 18 */ 19 public void add(Category category) throws SQLException { 20 String pid = null; 21 if(category.getParent() != null) { 22 pid = category.getParent().getCid(); 23 } 24 String sql = "insert into t_category(cid, cname, pid, `desc`) values (?,?,?,?)"; 25 Object [] params = {category.getCid(), category.getCname(), pid, category.getDesc()}; 26 qr.update(sql, params); 27 }