Dynamic array creation
Hi all... here's a good one for you...
I have a situation where I have some bean, and I need to populate an
array field in it... here's the problem... I do not know the element
type of the array before runtime.
Now, I've been planning on using Commons Beanutils, since the rest of
this particular app does (it's doing a lot of introspection of the
beans and such).
So, here's the question... can anyone figure out a way to dynamically
create an array at runtime? What I mean is, I want to do the
followig:
PropertyUtils.s etProperty(obj, fieldName,
((List)fieldVal ues).toArray()) ;
So, I want to set the field named by fieldName on the bean instance
referenced by obj, and I want to do it by taking the fieldValues List
and converting it to an array. Now, I can do:
PropertyUtils.s etProperty(obj, fieldName,
((List)fieldVal ues).toArray(ne w String[0]));
....and that's great, except that I don't know until runtime that the
field of the bean is of type String, it could be anything else. So,
how can I dynamically do the equivalent of the new String[0] is really
the question?
FYI, I don't really care if this is done with Beanutils, but I think
that's probably the logical course of action. Any ideas? Thanks all! 1 20547
"None" <no**@none.co m> wrote in message
news:3b******** *************** *********@4ax.c om... Dynamic array creation
Hi all... here's a good one for you...
I have a situation where I have some bean, and I need to populate an array field in it... here's the problem... I do not know the element type of the array before runtime.
Now, I've been planning on using Commons Beanutils, since the rest of this particular app does (it's doing a lot of introspection of the beans and such).
So, here's the question... can anyone figure out a way to dynamically create an array at runtime? What I mean is, I want to do the followig:
PropertyUtils.s etProperty(obj, fieldName, ((List)fieldVal ues).toArray()) ;
So, I want to set the field named by fieldName on the bean instance referenced by obj, and I want to do it by taking the fieldValues List and converting it to an array. Now, I can do:
PropertyUtils.s etProperty(obj, fieldName, ((List)fieldVal ues).toArray(ne w String[0]));
...and that's great, except that I don't know until runtime that the field of the bean is of type String, it could be anything else. So, how can I dynamically do the equivalent of the new String[0] is really the question?
FYI, I don't really care if this is done with Beanutils, but I think that's probably the logical course of action. Any ideas? Thanks all!
Use the Array.newInstan ce(Class, int) method: http://java.sun.com/j2se/1.5.0/docs/...g.Class,%20int)
(note that there's a close parenthesis at the end that's part of this URL).
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