Getter/Setter - Serialization

[Thomas Lehmann]

Hi,

probably a silly question. I have a class and some members will be
initialized only when calling a 'create' method. I'm using Eclipse and
there I get a warning "Found non-transient, non-static member. Please
mark as transient or provide accessors."

My question is now how to handle it correct. When I provide a setter
(assume a creation date) then I could set the creation date to another
as initialized when calling 'create'. That's why I wouldn't provide a
setter for this member. But obviously the warning want to tell me that
I might have problems with the serialization then obviously requiring
that the setter exists (and yes I'm intending to do serialization -
probably XML).

Could you please give some helpful comments on this?

 

[markspace]

I might have problems with the serialization then obviously requiring
that the setter exists

Yeah, I think the setter/getter might be required for XML style
serialization, but not in the general case.

What are you doing that Eclipse says you need to mark a field as
transient? This doesn't make sense to me, because general serialization
will handle this just fine. I think I need some context here.

Here's a good article on serialization:

<http://java.sun.com/developer/technicalArticles/Programming/serialization/>

 

[Thomas Lehmann]

The warning message comes with PMD (plugin).
I'm intending to use XStream for XML serialization and so far I can
see
there is no need to provide getter and setter.

I know that article (URL) but reading also "Effective Java" you will
be warned
about the problem with using "Serializable".

 

[markspace]

The warning message comes with PMD (plugin). I'm intending to use
XStream for XML serialization and so far I can see there is no need
to provide getter and setter.

I haven't used XStream; if you don't think there's a problem, I'd
ignore the PMD plug-in and just do the right thing. PMD is likely in error.

I know that article (URL) but reading also "Effective Java" you will
be warned about the problem with using "Serializable".

I don't have time to review EJ right now, care to refresh my memory what
is pertinent in EJ to this problem?

 

[lewbloch]

Hi,

probably a silly question. I have a class and some members will be
initialized only when calling a 'create' method. I'm using Eclipse and
there I get a warning "Found non-transient, non-static member. Please
mark as transient or provide accessors."

My question is now how to handle it correct. When I provide a setter
(assume a creation date) then I could set the creation date to another
as initialized when calling 'create'. That's why I wouldn't provide a
setter for this member. But obviously the warning want to tell me that

Did you declare the attribute as 'final'? If you want to protect a
member variable from change, that's often the best way. It has other
benefits as well.

I might have problems with the serialization then obviously requiring
that the setter exists (and yes I'm intending to do serialization -
probably XML).

Could you please give some helpful comments on this?

Could you please give us an SSCCE?
http://sscce.org/

As markspace points out, we need some context here.

To grok serialization, you should rigorously study the material in
Joshua Bloch's seminal book /Effective Java/, which thoroughly covers
the risks and best practices involved.
http://java.sun.com/docs/books/effective/
Chapter 11

 

[Arne Vajhøj]

The warning message comes with PMD (plugin).
I'm intending to use XStream for XML serialization and so far I can
see
there is no need to provide getter and setter.

I know that article (URL) but reading also "Effective Java" you will
be warned
about the problem with using "Serializable".

Yes.

But his arguments against serialization applies to xstream as
well, so ...

Arne

 

[Roedy Green]

Hi,

probably a silly question. I have a class and some members will be
initialized only when calling a 'create' method. I'm using Eclipse and
there I get a warning "Found non-transient, non-static member. Please
mark as transient or provide accessors."

Is this field for some reason non-serialisable? If it is serialisable,
you could just ignore the warning.