Implementing the Serializable interface

Hi guys,
I have a conceptual question about implementing the Serializable interface - since it's only a marker interface (i.e. - it doesn't have any abstract methods) why does Java demand an object to implement this interface in order to be written into a file? What I'm asking is why wouldn't they make the writeObject method's signature
public void writeObject(*Object* o)
so any object can get in? What is the point of forcing a class to implement an interface in order to enable it to be written to a file?

So that serialization requires the explicit consent of the class or superclass/superinterface.

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Hi,
I am not sure - given the information you provide - that you posted to the right forum
Frank

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See the type hierarchy below:
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┃
┣AbstractMap<K,V>
┃┃
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Thanks in advance.

georgemc wrote:
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899440 wrote:
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Im trying to understand the Serialization of objects?
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When you say the trace shows the ItreeIterator is wrong, do you mean it's not the correct class name or that there is an error coming back? If error, what's the message in the trace?
ross

A Bean must implement the java.io.Serializable interface? What makes the di

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Thanks for your help.
- Jeremy

I don't know, the assignment asks for it. I think I have to be able to write the objects into a file and read them back again later.

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Yep, it is basically just a marker interface to let Java know that this class is allowed to be serialized. You don't want to do this with sensitive information such as an User object with a password as unencrypted string property --in such case, you could also declare it transient and live with the fact that it doesn't come back after deserialization.

Is the remote interface implemented by some class

Hi,
I have a simple question, googled, no help.
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Sarvananda wrote:
Hi,
I have a simple question, googled, no help.look better...
I am trying to udnerstand, where exactly is the remote interface implemented ?
I mean, i know that it contains all the business methods which have a body in the bean. so, that's what implements it :)
But is the remote interface implemented somewhere ? Is there any class which implements the Remote interface ?
the bean class :)
But the actual implementor is a class generated by the appserver that delegates to the bean class.

Why do we need Serializable Interface since there is no method decl. inside

On working with Serialization in java
I could see that the Serializable Interface is empty without any method inside.
Also, the writeObject() and readObject() accepts only if the Serializable interface is implemented to a class.
What is the use of implementing an empty Interface?
Please clarify.
Thanks in advance.
Regards,
R.Mahendra Babu

The completely empty Serializable is only a marker interface -- it simply allows the serialization mechanism to verify that the class is able to be persisted.

Implementing the Serializable interface

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