Struts2:更新“对象列表"的值地图内 [英] Struts2: Updating the values of a "List Of Objects" inside a Map

问题描述

有一个对象ObjectA，它有一个ObjectB 的列表.ObjectB 中有一个 TreeMap.这个 TreeMap 有一个 String 作为键和一个 List 另一个对象 ObjectC 作为值.这个TreeMap和里面的list已经使用s:iterator和s显示在jsp上:textfield 并且显示正确.即 s:textfield 中的值"是正确的.现在，修改文本字段时会出现问题.我们如何在 action 类中捕获 ObjectC 中修改后的值?使用此处给出的代码，键(Key1")出现在操作中，但值为空.

There is an object ObjectA which has a list of ObjectB. There is a TreeMap inside the ObjectB. This TreeMap has a String as key and a List of another object ObjectC as value. This TreeMap and the list inside has been displayed on the jsp using the s:iterator and s:textfield and it is being displayed correctly. i.e. the "values" inside the s:textfield are correct. Now, the problem arises when the textfield is modified. How do we capture the modified values inside ObjectC in the action class? With the code given here, the key ("Key1") comes in the action but the value is null.

Java 代码

public class ObjectA implements Serializable {
private Integer attr1;
private List<ObjectB> objB;
//...getters and setters....
public class ObjectB implements Serializable {
private Integer attr11;
private TreeMap<String,List<ObjectC>> allPlainFields;
// ...getters and setters....
public class ObjectC implements Serializable {
private Integer attr111;
public String attr112;
// ...getters and setters....

JSP 代码

<s:iterator value="objA.objB" var="currentObjB" status="currentGroupStatus">

  <s:iterator value="#currentObjB.allPlainFields" var="parentMap" status="headerStatus">
     <s:iterator value="#parentMap.value" var="fieldList" status="fieldStatus">

       <s:textfield  name="objA.objB[%{#currentGroupStatus.index}].allPlainFields['%{#parentMap.key}'][%{#fieldStatus.index}].attr112"/>


</s:iterator>                       

 </s:iterator> 

HTML 呈现:<input type="text" id="review-act1_objA_objB_0__allPlainFields_'Key1'__6__attr112" value="正确值" name="objA.objB[0].allPlainFields['Key1'][0].attr112">

eclipse变量"视图中的对象结构显示:

objA    Object A  (id=955)  
objB    ArrayList<E>  (id=966)  
    elementData Object[10]  (id=967)    
        [0] ObjectB  (id=968)   
            allPlainFields  TreeMap<K,V>  (id=972)  
                comparator  null    
                descendingMap   null    
                entrySet    TreeMap$EntrySet  (id=979)  
                keySet  null    
                modCount    1   
                navigableKeySet null    
                root    TreeMap$Entry<K,V>  (id=980)    
                size    1   
                values  null    

        [1] ObjectB  (id=969)   
        [2] ObjectB  (id=970)   
        [3] ObjectB  (id=971)   
        [4] null    
        [5] null    
        [6] null    
        [7] null    
        [8] null    
        [9] null    
    modCount    4   
    size    4   

****在Eclipse变量"视图中，allPlainFields的值为**:** {Key1=}

****In the Eclipse "Variables" view, the value for allPlainFields is**:** {Key1=}

编辑(2013 年 2 月 27 日):

试过了，没用.这些值出现在 jsp 上，但在提交时，它们不会起作用:

Tried this but didn't work. The values appear on jsp but when submitted, they don't come in action:

在 Action 类中:

private TreeMap<String,ObjectCList> testTreeMap = new TreeMap<String,ObjectCList>();
//get,set and setting two keys in map "mykey1" and "mykey2"

在 ObjectCList 类中:

private ArrayList<ObjectC> paramMdlList;
 //default constructor, get, set

在JSP中:

<s:form id="test-map" method="post">
<s:iterator value="testTreeMap" var="pMap" status="hStatus">
     <li><label><s:property value="%{#pMap.key}" /></label> 
        <s:iterator value="%{#pMap.value.paramMdlList}" var="pList" status="innerStatus">
            <s:textfield name="testTreeMap['%{#pMap.key}'].paramMdlList[%{#innerStatus.index}].attr111"/>
            <s:textfield name="testTreeMap['%{#pMap.key}'].paramMdlList[%{#innerStatus.index}].attr112"/> 

        </s:iterator>


    </li>

</s:iterator>
<s:submit value=" " type='button' id="btnh1" action="saveTreeMap">
            <span>Save TreeMap</span>
</s:submit>
</s:form>

提交表单时，调用action的updateTreeMap方法.该地图按照此处所述打印:

When the form is submitted, updateTreeMap method of the action is called. The map is printed as mentioned here :

public String updateTreeMap(){

    for (Map.Entry<String, ObjectCList> entry : testTreeMap.entrySet())
    {
        System.out.println(entry.getKey() + "/" + entry.getValue());
    }

    return SUCCESS;

}

什么是打印":mykey1/mykey2/即空值

What is "printed" : mykey1/ mykey2/ i.e. null values

下面的屏幕显示了传入 jsp 的值

推荐答案

根据您的最新更新.如果您使用 TreeMap Struts2 无法正确确定其中的元素类型.将 testTreeMap 的声明从 TreeMap 更改为 Map.

According to your latest update. If you are using TreeMap Struts2 cannot correctly determine type of elements inside it. Change declaration of testTreeMap from TreeMap to Map.

private Map<String,ObjectCList> testTreeMap = new TreeMap<String,ObjectCList>();

或者用com.opensymphony.xwork2.util.Element注解testTreeMap来告诉Struts2里面的元素是什么类型的map.

Or annotate testTreeMap with com.opensymphony.xwork2.util.Element annotation to tell Struts2 what type are elements inside map.

@Element(value = ObjectCList.class)
private TreeMap<String,ObjectCList> testTreeMap = new TreeMap<String,ObjectCList>();

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