jstl中<c:forEach>的问题

                                  <c:if test="${b.Id==a.Id}">  

${b.Id==a.Id}

<c:forEach items="${ImgList}" var="row" varStatus="cou" >
    <c:if test="${cou.count eq 1 || (cou.count-1) % 4 eq 0}"><tr></c:if>
    <td colspan="2" >
        <a href="${pageContext.request.contextPath}/${row.url}" target="_blank">
            <div class="prod_item">
                <img src="${pageContext.request.contextPath}/${row.url}" title="${row.photoName}">
            </div>
        </a>
    </td>
    <c:if test="${cou.count % 4 eq 0 || cou.count eq 4}"></tr></c:if>
</c:forEach>