巴巴运动网学习笔记(86-90)

1.显示大类别下的所有产品
a.查找某个类别下面的所有子类及子类的子类　　

@SuppressWarnings("unchecked")
    @Transactional(readOnly=true,propagation=Propagation.NOT_SUPPORTED)//该方法为只读，不需要事务支持
    public List<ProductType> getChildsByParentId(Integer parentId){
        Query query = entityManager.createQuery("select t from ProductType t where t.parent.id = ?1");
        query.setParameter(1, (int)parentId);
        return query.getResultList();
    }
    
    public List<ProductType> getAllChildsByParentId(Integer parentId){
        List<ProductType> productTypeIds = new ArrayList<ProductType>();
        Queue<ProductType> temp = new LinkedList<ProductType>();
        ProductType p = find(ProductType.class, (int)parentId);
        while(p!=null){
            productTypeIds.add(p);
            List<ProductType> childIds = getChildsByParentId(p.getId());
            for(ProductType i : childIds){
                temp.offer(i);
            }
            p = temp.poll();
        }
        return productTypeIds;
    }

b.获取某个类别下面的所有产品

    /**
     * 根据产品类型id查找该产品类型及子类型下的所有产品的品牌
     */
    @SuppressWarnings("unchecked")
    @Transactional(readOnly=true,propagation=Propagation.NOT_SUPPORTED)
    public List<Brand> getBrandsByProTyId(int proTypeID){
        List<ProductType> productTypes = productTypeService.getAllChildsByParentId(proTypeID);
        //组拼根据ids查询产品的语句
        StringBuffer jpql2 = new StringBuffer("");
        for(int i=0;i<productTypes.size();i++){
            jpql2.append("?").append(i+1).append(",");
        }
        jpql2.deleteCharAt(jpql2.length()-1);
        StringBuffer jpql = new StringBuffer("select distinct b from Brand b where b.id in (select p.brand.id from Product p where p.productType.id in ("+jpql2+"))");
        Query query = entityManager.createQuery(jpql.toString());
        //为其设置参数
        for(int i=0;i<productTypes.size();i++){
            query.setParameter(i+1, productTypes.get(i).getId());
        }
        return query.getResultList();
    }

2.在前台页面中显示导航菜单和子类别

//设置导航数据
        Stack<ProductType> navigation = new Stack<ProductType>();
        ProductType parent = productService.find(ProductType.class,productForm.getProductTypeId());
        while(parent!=null){
            navigation.push(parent);
            parent = parent.getParent();
        }
        List<ProductType> navigationList = new ArrayList<ProductType>();
        while(!navigation.empty()){
            navigationList.add(navigation.pop());
        }

<div id="position">您现在的位置:&gt;&gt; <a href="/" name="linkHome">巴巴运动网</a> 
        <c:forEach items="${navigation}" var="nv" varStatus="state">
            <c:choose>
                <c:when test="${state.count==fn:length(navigation)}">&gt;&gt;<em>${nv.name }</em></c:when>
                <c:otherwise>&gt;&gt;<a href="<html:rewrite action='/product/list'/>?productTypeId=${nv.id }">${nv.name }</a></c:otherwise>
            </c:choose>        
        </c:forEach>
    (${pagingBean.totalRecords })
    </div>

<div class="browse_t">${productType.name}</div>
            
                <h2><span class="gray">浏览下级分类</span></h2>
                <ul>
                    <c:forEach items="${productType.child}" var="proType" >
                        <li class='bj_blue'><a href="<html:rewrite action='/product/list'/>?productTypeId=${proType.id }">${proType.name }</a></li>    
                    </c:forEach>
            </ul>
         </div>

3.在前台页面中显示最畅销产品的技术分析
 a.某一个产品类别下面的
 b.后台推荐的
 c.按照销量进行排序
 d.使用ajax技术，进行异步显示
4.使用ajax技术展示最畅销产品

a.获取最畅销产品的业务方法

/**
     * 查找某个类别下面的最畅销的商品
     * @param productTypeId 类别id
     * @param maxCount 查找个数
     * @return
     */
    @SuppressWarnings("unchecked")
    public List<Product> getTopsellProduct(int productTypeId,int maxCount){
        List<ProductType> productTypes = productTypeService.getAllChildsByParentId(productTypeId);
        //组拼根据ids查询产品的语句
        StringBuffer jpql2 = new StringBuffer("");
        for(int i=0;i<productTypes.size();i++){
            jpql2.append("?").append(i+2).append(",");
        }
        jpql2.deleteCharAt(jpql2.length()-1);
        StringBuffer jpql = new StringBuffer("select p from Product p where p.commend = ?1 and p.productType.id in ("+jpql2+") order by sellCount desc");
        Query query = entityManager.createQuery(jpql.toString());
        //为其设置参数
        query.setParameter(1, true);
        for(int i=0;i<productTypes.size();i++){
            query.setParameter(i+2, productTypes.get(i).getId());
        }
        query.setFirstResult(0).setMaxResults(maxCount);
        return query.getResultList();
    }

b.处理请求的manageraction

@Controller("/product/manager")
public class FrontProductManagerAction extends DispatchAction {
    @Resource(name="productServiceImpl")
    ProductService productService;
    public ActionForward getTopsell(ActionMapping mapping, ActionForm form,HttpServletRequest request, HttpServletResponse response)
    throws Exception {
        FrontProductForm productForm = (FrontProductForm)form;
        request.setAttribute("topsell", productService.getTopsellProduct(productForm.getProductTypeId(), 10));
        return mapping.findForward("list");
    }
}

c.页面的代码

<SCRIPT LANGUAGE="JavaScript">
<!--
    function getTopSell(typeid){
        var salespromotion = document.getElementById('salespromotion');        
        if(salespromotion && typeid!=""){
            salespromotion.innerHTML= "数据正在加载...";
            send_request(function(value){salespromotion.innerHTML=value}, "<html:rewrite action='/product/manager'/>?method=getTopsell&productTypeId="+ typeid, true);
        }
    }
    function pageInit(){        
        getTopSell("${productType.id}");
    }
//-->
</SCRIPT>

<body class="ProducTypeHome2" onload="JavaScript:pageInit()">

<DIV class="lanmu_font">最畅销户外用品</DIV>
        <DIV style="PADDING-LEFT: 10px; COLOR: #333333" id="salespromotion">

5.修正按品牌和性别过滤的一些bug