logic标签用法

logic
    <logic:iterate>
<%
        Dog dog1=new Dog();
        dog1.setAge(2);
        dog1.setName("xiaoming");

         Dog dog2=new Dog();
        dog2.setAge(2);
        dog2.setName("xiaoming");
         Dog dog3=new Dog();
        dog3.setAge(2);
        dog3.setName("xiaoming");

        LinkedList linkedList=new LinkedList();
        linkedList.add(dog1);
        linkedList.add(dog2);
        linkedList.add(dog3);
        request.setAttribute("dogList",linkedList);
     %>

     <h1>strust-logic</h1>
     <logic:iterate id="dog" name="dogList">
         ${dog.name}||${dog.age}
     </logic:iterate>
name:是指域对象的名字。id是要集合中的单个对象
    <logic:empty〉
判断是否是空对象
<logic:empty name="ww">
         ww不存在
</logic:empty>

    <logic:netEmpty>
判断不为空
<logic:notEmpty name="dogList">
        dogList中存在的
</logic:notEmpty>
    <login:greaterThan>
<logic:greaterThan value="20" name="dog" property="age">
             ${dog.age }大于20
 </logic:greaterThan>
如果name这个对象的属性大于20就输出。