在JSP中使用EL计算Colloction的大小

载入functions taglib <%@ taglib uri=”http://java.sun.com/jsp/jstl/functions” prefix=”fn”%>

计算collection的size ${fn:length(your_collction)}

length函数的描述如下

fn.tld
<function>

    <description>

      Returns the number of items in a collection, or the number of characters in a string.

    </description>

    <name>length</name>

    <function-class>org.apache.taglibs.standard.functions.Functions</function-class>

    <function-signature>int length(java.lang.Object)</function-signature>

    <example>

      You have ${fn:length(shoppingCart.products)} in your shopping cart.

    </example>

 </function>