前台开发------------开发新品推荐在首页显示

Posted 2021-02-14 jiguiyan

没有连接数据库之前：

同上一节热销推荐几乎一样，代码如下：

只有SQL语句中的type的值不一样，热销的type=2,新品的type=3

 

因此我们在GoodsDao.java中的SQL语句将type设置等于？并新加一个参数recommendType

public  List<Map<String, Object>>  getGoodsList(int recommendType) throws SQLException  {
        
        
        QueryRunner r=new QueryRunner(DBUtil.getDataSource());
        String sql="select g.id,g.name,g.cover,g.price,t.name typename from recommend r,goods g,type t where type=2 and r.goods_id and g.type_id=t.id";
        return  r.query(sql,new MapListHandler(),recommendType);
    
    }

 

当type=3时，在数据库中查询的结果：

 

GoodsService.java

public List<Map<String, Object>>  getNewGoodsList(){
        
        
         List<Map<String, Object>> list=null;
            try {
                list = gDao.getGoodsList(3);
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            
             
             
             return list;
    }

IndexServlet.java

//取得新品商品
        List<Map<String, Object>> newList=gService.getHotGoodsList();
        request.setAttribute("newList", newList);

index.jsp

<div class="alert alert-info">新品推荐</div>
            <div class="gallery-grids">    
                <c:forEach items="${newList}" var="g">
                    <div class="col-md-3 gallery-grid ">
                        <a href="detail.action?goodid=14">
                            <img src="${pageContext.request.contextPath }${g.cover}" class="img-responsive" alt="${g.name}"/>
                        </a>
                        <div class="gallery-info">
                            <p>
                                <span class="glyphicon glyphicon-eye-open" aria-hidden="true"></span> 
                                <a href="detail.action?goodid=14">查看详情</a>
                            </p>
                            <a class="shop" href="javascript:;" onclick="buy(14)">立刻购买</a>
                            <div class="clearfix"> </div>
                        </div>
                        <div class="galy-info">
                            <p>${g.typeName}> ${g.name}</p>
                            <div class="galry">
                                <div class="prices">
                                    <h5 class="item_price">¥ ${g.price}</h5>
                                </div>
                                <div class="clearfix"></div>
                            </div>
                        </div>
                    </div>
                    </c:forEach>
                
                    
                
    </div>    

最终新品推荐经过数据库的连接显示的商品：