[SOLVED] What is the correct request parameter for map proprerty inside an object in Struts Action?

What is the correct request parameter for map proprerty inside an object in Struts Action?

Consider the following AnswerAction:

public class AnswerAction extends CommonAction implements SessionAware {

    private CaseNumbering caseNumbering;
    (...)
}

And FormCaseNumbering

public class FormCaseNumbering implements CaseNumbering {

private Duplicable innermostElement;
Map<Duplicable, Integer> caseNumbersOfDuplicableFormElements = new HashMap<>();
(...)
}

and DuplicableFormElement

public class DuplicableFormElement implements Duplicable {

protected int id;
protected boolean duplicable;
}

In a Struts2 application where beans are injected via spring:

<bean id="caseNumbering" scope="prototype"
    class="model.FormCaseNumbering">
    <property name="innermostElement" ref="duplicableFormElement"></property>
</bean>


<bean id="answerAction" class="actions.AnswerAction" scope="prototype" autowire="byName">
    <property name="caseNumbering" ref="caseNumbering"/>
</bean>

Question:

How can you send a request parameter that populates the action with a caseNumbering containing a Map element with key duplicableElement.id=6 and value Integer=1 ?

My attempts:

Since the caseNumbering element is being injected via spring, I have no problem populating innermostElement , eg this works:

(MockHttpServletRequest)request.setParameter("caseNumbering.innermostElement.id","9");

However the following:

(MockHttpServletRequest)request.setParameter("caseNumbering.caseNumbersOfDuplicableFormElements[6]","1");

will fail with:

Invalid field value for field "caseNumbering.caseNumbersOfDuplicableFormElements[6]".

I have also tried adding an AnswerAction-conversion.properties with the following, with no luck:

Key_caseNumbering.caseNumbersOfDuplicableFormElements=model.DuplicableFormElement
KeyProperty_caseNumbering.caseNumbersOfDuplicableFormElements=id
Element_caseNumbering.caseNumbersOfDuplicableFormElements=java.lang.Integer
CreateIfNull_caseNumbering.caseNumbersOfDuplicableFormElements=true

Is this possible in Struts2 (without needing to create a custom converter)?

Solution

This is a similar question: Struts 2 map type conversion

And the answer, which can be found in struts2' mailing list, is still valid.

In short - there is a limitation in struts2 to handle this type of map and a custom converter is needed.