Re: persistent object?
Lew wrote:
If it's not new news that you're taking on a lot of responsibility to
use 'Serializable', so much the better. It is enough of a surprise to
enough people that it's worth mentioning. Joshua Bloch's major
chapter on the subject goes into the details. He also outlines many
ways to lessen the burden.
Arne Vajh??j wrote:
But practically all the problems would be the same no matter how
the objects were persisted. If the objects need to be completely
reconstructed when read again then all implementation information
somehow has to be there.
I have a rather pragmatic view on that. Serialization is OK for
short term transfer like write to a socket. Serialization is bad for
long term transfer like saving in a file. If an object has to
be saved in a file, then I usually suggests XML. Sure it is possible
to make incompatible changes to the class later on, but with an
XML format it is much easier to convert a file from old to new
format.
XML serialization is serialization still. However, my comments are more
specific to the use of 'java.io.Serializable'. Because of the built-in
support in Java for that type, there are special considerations for it. I
agree with your points about short-term persistence and the advantages of XML
serialization. In addition, there are advantages to XML being human-readable
and cross-platform.
--
Lew
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