[Springframework-developer] Re: [springframework - Help] Index properties in forms

[Rod J. <rod...@in...>]

Juergen,

I think we should provide indexed property support for M3.  I think you were
right to remove the inadequate support for now.

I think supporting the Commons syntax makes sense. I think at one point I
envisaged having an IndexedPropertyValue class, but that's probably
unnecessary.

Regards,
Rod

-----Original Message-----
From: jürgen höller [werk3AT]
Sent: Thursday, October 23, 2003 4:50 PM
To: spr...@li...
Subject: FW: [springframework - Help] Index properties in forms


Everybody,

Seems like we've got two people inquiring for indexed property support. The
second already dates back to mid-September :-(

I've just rechecked the BeanWrapper implementation and discovered that there
is no proper support for indexed properties yet. The existing
getIndexedProperty method was not complete (e.g. no support for nesting) and
untested (no unit test covered it), so I've decided to remove it for the
time being (for 1.0 M2). It just confused both of those guys that were
looking for indexed property support.

Jakarta Commons BeanUtils does support nested and mapped properties, quoting
from the javadocs of their PropertyUtils class:

<quote>
For the purposes of this class, five formats for referencing a particular
property value of a bean are defined, with the layout of an identifying
String in parentheses:

* Simple (name) - The specified name identifies an individual property of a
particular JavaBean. The name of the actual getter or setter method to be
used is determined using standard JavaBeans instrospection, so that (unless
overridden by a BeanInfo class, a property named "xyz" will have a getter
method named getXyz() or (for boolean properties only) isXyz(), and a setter
method named setXyz().

* Nested (name1.name2.name3) The first name element is used to select a
property getter, as for simple references above. The object returned for
this property is then consulted, using the same approach, for a property
getter for a property named name2, and so on. The property value that is
ultimately retrieved or modified is the one identified by the last name
element.

* Indexed (name[index]) - The underlying property value is assumed to be an
array, or this JavaBean is assumed to have indexed property getter and
setter methods. The appropriate (zero-relative) entry in the array is
selected. List objects are now also supported for read/write. You simply
need to define a getter that returns the List

* Mapped (name(key)) - The JavaBean is assumed to have an property getter
and setter methods with an additional attribute of type java.lang.String.

* Combined (name1.name2[index].name3(key)) - Combining mapped, nested, and
indexed references is also supported
</quote>

The question is: When and how to we add support for indexed and mapped
properties? I guess that if we do, we should adopt the Commons BeanUtils
style of specifying property paths for index and map access. This means that
we wouldn't need additional methods in the BeanWrapper interface but rather
just support for respective property paths in the BeanWrapperImpl
implementation.

Any thoughts on this? I've completely forgotten about these things in face
of all the enterprise stuff we've been addressing lately ;-)

Juergen


https://sourceforge.net/forum/message.php?msg_id=2251775
By: breidenr

I am using a SimpleFormController to help create an object using an HTTP
form.
Obviously, if my form object is a Vendor, that object has a setName(String)
method, and my HTTP form has a field named "name", the Controller will try
call
Vendor.setName(String) and pass in the value from the form. This also goes
for
nested properties: address.setCity -> vendor.getAddress().setCity(String).

My question is, is there any support for *indexed* properties? By that, I
mean
purchaseOrder[0].number -> ( (PurchaseOrder)
vendor.getPurchaseOrders().get(0)).setNumber(). I know that some expression
languages support something like this. IIRC, Struts has something like this,
but it has a little kludgy.

From what I can tell, nested porperies are supported by the Spring
BeanWrapperImpl,
but that is it. If this is correct and I want to implement nested
properties,
any suggestion as to the best route.

Thanks.

Ryan



Read and respond to this message at:
https://sourceforge.net/forum/message.php?msg_id=2193984
By: hogie

Hi,



If I have a command object that stores a collection and I want the data
binder
to populate that collection from the servlet request, how should I name the
parameters in my servlet request?


In Struts I can do field[index], but I can't see if the same is possible in
Spring.  I see BeanWrapper.getIndexedPropertyValue() , but no set()
equivalent.


Many thanks,

Mike.