jstl换行

在实际开发中遇到jstl换行问题，贴出来共享！！！
一.3列换行
<c:forEach var="i" begin="0" end="${size}" step="3">
<tr align="center" bgcolor="#FFFFFF">
<c:forEach var="product" items="${Product}" begin="${i}" end="${i+2}">
<td >${product.productName}</td>
<c:if test="${(i+1)==size&&size%3==1}">
<td> </td>
<td> </td>
</c:if>
</c:forEach>
<c:if test="${(i+2)==size&&size%3==2}">
<td> </td>
</c:if>
</tr>
</c:forEach>

二.4列换行
<c:forEach var="i" begin="0" end="${size}" step="4">
<tr align="left" height="25">
<c:forEach var="list" items="${retList}" begin="${i}" end="${i+3}">
<td ><a href="javaScript:toJD('${list['streetid']}','${list['streetname']}')" >${list["streetname"]}</a></td>
<c:if test="${(i+1)==size&&size%4==1}">
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td> 
</c:if> 
<c:if test="${(i+2)==size&&size%4==2}">
<td>&nbsp;</td>
<td>&nbsp;</td>
</c:if>
</c:forEach>
<c:if test="${(i+3)==size&&size%4==3}">
<td>&nbsp;</td>
</c:if>
</tr>
</c:forEach>
以此类推...