Thanks for your response Mike. I think you must have copy-pasted from another
post or something, I am not working with a Country object. But I think your
idea applies to both of my scenarios.
In scenario (1) I already have a PropertyEditor defined for StreetSection.
It looks like this:
public class StreetSectionPropertyEditor extends PropertyEditorSupport
{
public void setAsText(String id) {
StreetSection streetSection = streetSectionManager.get(new Long(id));
setValue(streetSection);
}
And it seems to work fine. I don't have a getAsText() defined and it has
worked until now. But I am unsure of what I should use in the
establishmentform.jsp. Should I use:
<form:hidden path="streetSection" id="streetSection" /> or
<form:hidden path="streetSection.id" id="streetSection.id" /> ?
It was working ok using 'streetSection' instead of 'streetSection.id' but I
had problems when saving a NEW establishment (it worked fine when saving an
existing Establishment curiously enough ...), 'can't save a transient
object' error. Could this be because I don't have getAsText() defined?
In scenario (2), how would I go about creating an
EstablishmentContainerPropertyEditor? What I would need to do is tell
Spring, 'Hey! Create an EstablishmentContainer object with '1' for
idEstablishment, '2' for idContainer and '50' for quantity, and add it to
the list of EstablishmentContainers, using values from the .jsp, either a
multi-select or hiddens. But the setAsText() method takes only one string,
usually an id. Do I need to override some other method in
PropertyEditorSupport?
I think this is the way to go though, just not sure how to do it.
Thanks!
Bob
Mike Horwitz wrote:
>
> I believe you could resolve both cases by registering custom editors in
> your
> controllers - this would allow Spring MVC to automatically convert between
> the object and its string representation. See the thread on this
> discussion
> for more details http://tinyurl.com/3yghfd:
>
> You are going to need to provide *Spring* *MVC* with a way to get from an
> id
> to a country and vice-versa. As you correctly point out this is done by
> registering a custom property editor in your controller. To do this you
> need
> to:
>
> 1) Extend the class *PropertyEditorSupport* to create the property editor:
> http://java.sun.com/j2se/1.5.0/docs/api/java/beans/*PropertyEditorSupport*.html
> <http://java.sun.com/j2se/1.5.0/docs/api/java/beans/PropertyEditorSupport.html>
>
> You need to override the getAsText() and setAsText() methods. The first
> should call getValue() and return the id as text, and the second should
> accept a text id and call setValue() on the editor with the corresponding
> country object.
>
> 2) You then register this custom editor using one of the appropriate
> methods
> on your controller: initBinder() see api on http://tinyurl.com/2sutrm
>
> And it should all work like magic....
>
> Mike.
>
>
> On 10/2/07, syg6 <[EMAIL PROTECTED]> wrote:
>>
>>
>> I have a couple scenarios, one typical the other not so much, that I am
>> trying to implement as quickly and easily as possible.
>>
>> The first is pretty straight-forward:
>>
>> @Entity
>> public class Application
>> ...
>> private StreetSection streetSecion;
>> ...
>> @ManyToOne(cascade = { CascadeType.PERSIST, CascadeType.MERGE })
>> @JoinColumn(name="streetSection", nullable=false)
>> public StreetSection getStreetSection()
>> {
>> return streetSection;
>> }
>>
>> In my form, which is the correct way to do the input?
>>
>> <form:hidden path="streetSection" id="streetSection" />
>>
>> or
>>
>> <form:hidden path="streetSection.id" id="streetSection.id" />
>>
>> In my testing I have found that they both work but each one has its own
>> little quirks. For example, if I use 'streetSection.id', when it's a new
>> Application the page crashes because streetSection.id is null. So I have
>> to
>> put a <c:if> in there and if it's null just use a normal <input
>> type='hidden'> tag.
>>
>> If I use 'streetSection' I believe (I've done so many tests I forget ...)
>> that Hibernate is giving me 'can't save transient object' errors. Anyway,
>> just curious what the best practice is.
>>
>> The other scenario is more complicated. I have an object, Establishment,
>> and
>> another, Container, and they both have a list of EstablishmentContainer
>> objects, which saved in a join table that has an attribute, quantity. So
>> each POJO, Establishment and Container, have a OneToMany relationship
>> with
>> EstablishmentContainer, and EstablishmentContainer has a ManyToOne
>> relationship with both Establishment and Container. This is apparently
>> the
>> best way to map join tables with attributes.
>>
>> @Entity
>> public class Establishment
>> ...
>> private List<EstablishmentContainers> establishmentContainers;
>> ...
>> @OneToMany(mappedBy="establishment", fetch = FetchType.EAGER, cascade = {
>> CascadeType.PERSIST, CascadeType.MERGE })
>> public List<EstablishmentContainer> getEstablishmentContainers()
>> {
>> return establishmentContainer;
>> }
>>
>> @Entity
>> public class Container
>> ...
>> @OneToMany(mappedBy="container")
>> public List<EstablishmentContainer> getEstablishmentContainers ()
>> {
>> return establishmentContainers;
>> }
>>
>> @Entity
>> public class EstablishmentContainer extends
>> {
>> private Long id;
>> private Establishment establishment;
>> private Container container;
>>
>> private int quantity;
>> ...
>> @ManyToOne
>> @JoinColumn(name="idEstablishment")
>> public Establishment getEstablishment()
>> {
>> return establishment;
>> }
>>
>> @ManyToOne
>> @JoinColumn(name="idContainer")
>> public Cubo getContainer()
>> {
>> return container;
>> }
>>
>> @Column(name="quantity")
>> public int getQuantity()
>> {
>> return quantity;
>> }
>>
>> In my EstablishmentFormController do I have to do the following for each
>> EstablishmentContainer created in the page:
>>
>> 1. instantiate an EstablishmentContainer object
>> 2. fill it it request parameters by hand
>> 3. add it to a List
>> 4. assign that list to my Establishment object
>>
>> ... for the EstablishmentContainers list to be properly saved when I do
>> an
>> establishmentManager.save()?
>> This is what I am doing currently and it works but it seems to me that if
>> I
>> put the following in my jsp:
>>
>> input type="text" id="establishmentContainers.container.id"
>> input type="text" id="establishmentContainers.establihsment.id"
>> input type="text" id="establishmentContainers.quantity"
>>
>> Spring should be able to populate the List of EstablishmentObjects
>> automatically, just as in the first example it populates my
>> Application.StreetSection object when I put a
>>
>> input type="text" id="application.streetSection"
>>
>> element in the page. If it's not possible I can keep doing it the way I
>> currently do, I just don't want to reinvent the wheel.
>>
>> Sorry for the long post. I look forward to any and all responses.
>> Bob
>>
>> --
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>> Sent from the AppFuse - User mailing list archive at Nabble.com.
>>
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>
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