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From Aaron Longwell <>
Subject BeanUtils.copyProperties() Conversion Question
Date Sat, 28 Jun 2003 21:08:36 GMT
I'm new to this list... and new to BeanUtils as well. Somebody pointed 
out the BeanUtils.copyProperties method to me the other day... and WOW! 
It's a great function.... just one issue:

I'm using it in a struts application. On one edit form, I've got a 
number of Integer fields. Some of these can have an empty (null) value. 
When I populate the form, a null Business Object value converts to a 
blank string on the input form (this is what I want). Now, when I save 
that form back to the database, the empty string gets converted to a 0 
and stored in the database as a 0. Obviously, when the user edits the 
same object again, now the form is populated with a 0.

As a workaround, I am doing a manual check after the copyProperties 
method runs and storing null when the source string was empty.

Why does an empty string automatically convert to 0 when converted to an 
Integer (instead of null)?
Is there a way to alter the default conversions that occur?
Is there a way to alter the conversions on a per-property basis? (For 
some fields the blank->0 conversion may be desirable)

Thanks for the help,

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