Binding with ArrayList in Spring

[pasquale vitale]

Hi all, I'm new with spring framework.

I have a bean AddExameForm with this parameters:

private String esame;
private String descrizione;
private List<Domanda> domande;

and the costructor is:
//initilize ArrayList with objects domanda
domande = new ArrayList<Domanda>(10);
for (int i=0;i<10;i++){
domande.add(new Domanda());
}

... setter and getter methods;

and bean Domanda is a bean with:

private String domanda;
... setter and getter

Now I want to populated my bean AddExameForm (with domande) and I using a binding; in the other words I want a form with 10 input (type=text) where I want to write my 10 strings (text) and then when I push a submit button I want to initialize my bean (my List domande) with my 10 strings.

My jsp code is:

<c:forEach varStatus="i" var="domande" items="${addExameForm.domande}">
<tr>
<td class="blank"><cut value="${i.count}" /></td>
<td class="blank">
<spring:bind path="addExameForm.domande[${i.index}].domanda">
<input type="text" name="<cut value="${status.expression}"/>" value="<cut value="${status.value}"/>">
<font color="red"><cut value="${status.errorMessage}" /></font>
</spring:bind>
</td>
</tr>
</c:forEach>

when I submit form I have this error:

javax.servlet.ServletException: org.springframework.beans.InvalidPropertyException : Invalid property 'domande[0]' of bean class [springweb.form.admin.AddExameForm]: Index of out of bounds in property path 'domande[0]'; nested exception is java.lang.IndexOutOfBoundsException: Index: 0, Size: 0

Can you help me?
Thanks Pasquy

[Vyas Sanzgiri]

Sorry but I am trying to revive an old thread. This is important for me. I am still not able to figure this out

[Hong Anderson]

It should work. Have you tried debug? Does the constructor get called?

Anyway, next time you should post in Spring forum (in this website).

[Nathan Pruett]

Yes, I would add debug to the constructor, *and* to the getter and setter - there may be something in the flow of the logic generating the page that looks for an existing "domande" value and if one isn't found sets it to an empty ArrayList.

[Vyas Sanzgiri]

I believe this is a known issue in Spring but I cannot find the work around

[Hong Anderson]

Vyas Sanzgiri wrote:I believe this is a known issue in Spring but I cannot find the work around

I don't think so. If it's a bug, it needs to be fixed. It's very normal to access an item in list.

Anyway, have you debugged?

[Vyas Sanzgiri]

Try it. Its not a bug it is an issue which has some work around. It is very difficult for me to get into the details of Spring as I have not debugged the framework.

Spring spits of all sorts of DEBUG level messages

[Hong Anderson]

I have no problem binding to items in list. What is your Spring version?
If Spring cannot do that, it's a bug for sure.

[Vyas Sanzgiri]

Spring MVC 2.5. Can you share your code?

[Hong Anderson]

I use SimpleFormControler, create empty items and add to list in formBackingObject method.
In JSP I use something like:

<form:input path="list[${status.count-1}].property"

There is no problem.

It's a very basic feature, Spring must be able to do this.

[Vyas Sanzgiri]

I am using annotations.

In my form I had to declare List as follows:

 private List<PidProcessParam> processParameters = ListUtils.lazyList(new ArrayList<PidProcessParam>(), FactoryUtils.instantiateFactory(PidProcessParam.class));

Otherwise it gives me InvalidPropertyException IndexOutOfBoundsException