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。