asked on

not saving

Hi experts,
I got some help with a question last week were I was trying to save my 2 arrays of classes(doctors and hospitals)

both these classes have string, boolean and integer (and even a class) attributes.

the code used saves the array and a string attribute"name" but it doesnt seem to save the boolean or class attribues

here is part of the code. if you have any solutions or alternatives please include code

try {XMLEncoder r = new XMLEncoder(new BufferedOutputStream(new FileOutputStream(fileName)));}

catch (Exception x) {x.printStackTrace();}

r.writeObject(allDoctors);
r.writeObject(allHospitals);
r.close();
}

thank you

Mick Barry

XMLEncoder is limitied in what it can do, depending on how your class is written.
It is designed to work on beans.

If you just want to serialize your class to be read by another Java application then ObjectOutputStream is perhaps a better approach.

Samooramad

ASKER

how do I need to change the code?

ASKER CERTIFIED SOLUTION

Mick Barry

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Samooramad

ASKER

just change the declaration to JavaBeans instead of class?

also, what do I need to import for your code objects?

Samooramad

ASKER

if I change to java beans will they still work or will it affect other aspects of the program?

Mick Barry

> also, what do I need to import for your code objects?

import java.io.*;

What are you using the serialized instance for?

Samooramad

ASKER

I dont know what you mean
I got an error by the way.
not serializable object on one of the lines

Mick Barry

I meant why do you need to save you object(s) to a file.

> I got an error by the way.
> not serializable object on one of the lines

Sorry forgot to add you'll need to make your class implement Serializable

eg.

public class Doctor implements java.io.Serializable
{
...

Samooramad

ASKER

oh ok :) will try that and see if I get any more trouble :)

thanks

Samooramad

ASKER

to answer your question I have an array of class Doctor and an array of class Hospital, some calculations are done then some doctors are set as employees of certain hospitals (obviously more than one doctor ends up in each hospital). I just need to save the final result (meaning all hospital names and all the employees in them)

got any pointers?

thanks

Mick Barry

Serialization should be fine then.

Samooramad

ASKER

I dont get errors but it still isnt working..
say I only want to save certain fields in each element of the array ..like in the hospital class, I only want to save the name attribute(string) and the employee attribute(array of String)
how do I go about doing that?
and how do I read them?

thanks for the help

Mick Barry

How exactly is it not working?

Samooramad

ASKER

it saves the "name" attribute but doesnt seem to save the others..

Samooramad

ASKER

I really only need to save the two attributes "name" and the employee array. is there any way to just save those two?

Mick Barry

yes, call the writeObject() method on each object you want to save:

out.writeObject(a);
out.writeObject(b);
out.writeObject(c);

Samooramad

ASKER

ok will try that

thanks