Re: Java Bean Question

From:

Lew <lew@lewscanon.com>

Newsgroups:

comp.lang.java.programmer

Date:

Mon, 08 Oct 2007 04:20:19 -0400

Message-ID:

<VOadnaw9u4HedZTanZ2dnUVZ_hisnZ2d@comcast.com>

Chris ( Val ) wrote:

Hi gang,

Are all Java Beans the same?

What I'm getting at is that I have seen some examples
on the internet that show sample Java Beans created
without them implementing the Serializable interface.

So if I use a Simple Java Bean with implementing the
Serializable interface, invoking it from withing a JSP
via "use:bean..." [sic], is it still a valid / legal Java Bean?

Yes. The question of being a JavaBean is not a question of being Serializable.

Primarily to be a JavaBean means to follow the convention that there is a
getX() and setX() for all properties X, except booleans which have an isX()
and setX() method.

There are also notifications and events connected to beans, but that doesn't
affect the ability to use <jsp:useBean> or <c:set> or Expression Language (EL)
references.

You do need to make an object Serializable to safely make it a session object.

Making a class Serializable incurs a huge responsibility. Serialization is
another public interface to a class, and it exposes the implementation
(private members). Joshua Bloch covers the issues in his seminal book
/Effective Java/.

Just follow the accessor (getX() or isX()) and mutator (setX()) method
conventions for all attributes and your class will work with JSPs just fine
for scope less than session.

--
Lew