评估列表是否为空JSTL

Question

我一直在尝试评估此数组列表是否为空，但是这些都没有被编译：

<c:if test="${myObject.featuresList.size == 0 }">                   
<c:if test="${myObject.featuresList.length == 0 }">                 
<c:if test="${myObject.featuresList.size() == 0 }">                 
<c:if test="${myObject.featuresList.length() == 0 }">                   
<c:if test="${myObject.featuresList.empty}">                    
<c:if test="${myObject.featuresList.empty()}">                  
<c:if test="${myObject.featuresList.isEmpty}">  

我如何评估ArrayList是否为空？

Answer 1

empty运算符是prefix

Answer 2