Elena Taube

Hello everyone,
I am trying to describe my Interfaces and have following lack of understanding. I will show with the example in order to describe my problem:

I have defined a method in my Interface:
void changeObject(int position);
It changes an object at specified position. How can I describe the case if the object could not be found at this position as Precondition or Error?

precondition -> No object could not be found.

Error -> There is no object was found.

Could you help me?
Thanks a lot!

Could you make an example for VO and TO? Thanks a lot!

Hello Everyone,

what are the differences between Value Object and Transfer Object?

Thanks a lot!

I am decided to use the MVC model in my rich-Client Application (frontend is implemented with Swing,
Its' J2EE Client-Server Applikation).
I am trying to divide my Controller in the following function parts:
ActionController, DialogController and ModelController. The ActionController is responsible
for handling the user's action. The DialogController manages the view. ModelController
comunicates with the model part (some business objects).
But I am not sure if this separation is correct?
Maybe you have another idea about the functional separation of the Controller.
Thanks a lot for your help!
[ July 11, 2006: Message edited by: Elena Taube ]

Hello,

I am thinking about to make architecture of client-tier of my J2EE application. And have some problem to begin. There is a lot information about JSP or Servlets, but I found only litte information/examples about what patterns are suited to make the client artitecture for rich (fat) client (Swing-Application). The application should be data managing tool (the user recieves some forms to create data, can save it, cann call this data, can edit this data).
I have read about Front Controller. But only examples that i found was Servlets or JSP Can this pattern be applied to the rich-client?
Or what is the alternative for this?
Are there another patterns that I can use to create the architecture of the client tier?
Have you met maybe some examples of the client architecture for rich-client?

Any help are appreciated!
Elena
[ July 04, 2006: Message edited by: Elena Taube ]

Hi Jeanne,

thanks a lot for your reposponce.
I thought if I knew a list of my primary key, I could find all records That is why i have asked about the list of the pk.
Than I found that I can write find method, and I have implemented it together with ejb ql. It works fine!

Hello,
My LocalHome interface contains only 2 methods: create and findByPrimaryKey.
But how can I retrieve all primary keys?
Thanks a lot!

Hi Mark,

Thanks a lot for your fast answer.
The xml file should be saved (on hard drive) on the client. That is my problem.

But I�m not sure, if it is a good idea to generate XML on the server.

1. XML file generate on the client.
The client receives the information from the server and use it for the XML generation.

2.XML file generate on the server.
The server generate XML and transfer it to the client as one object. But what object can I use to transfer?

I�m not sure if the using of the JDOM is a good idea. I am thinking about to create it with StringBuffer or with java.io.Writer.
How do you think about it?
Thank a lot!

Hi everyone,
my client should create the XML files and save it on the hard drive. As the information that should be written in the XML file is on the server, my server (one EJB) will perform the XML- creation operation. I am planning to use JDOM for XML creation.
After the xml object is created the server returns it to the client.

My question is: What type (String, org.jdom.Document, OutputStream or etc.) is the better to use for transfer the XML object from the server to client?
Thanks a lot for your help!

Hi all,

I am sorry for my absurd question But I am a perfectionist and this is my problem
When you mention a class in your choices.txt documentation, do you use only class name or the class name with the package name? Could you give me an advice how to make this document as an assessor-friendly one?

For example:
Bla-bla bla MyClasss is bla-bla�

Or
Bla-bla bla suncertify.mypackage.MyClasss is bla-bla�

Thanks for your comments!

Hi all,

I wrote the user documentation and saved it in the html-files. These files contain some images that I placed in img directory. Can I place this img directory in the docs directory (that was mentioned by SUN�s instruction)?
Have you placed this images in another directory?

Thanks a lot for your help!

In the instruction that we have, the maximum point for the server part is 40.

But my server part is only one class that is called Server, that creates and binds the ConnectionFactory to the LocateRegistry and contains small GUI for shutting-down or configure of the server.

Is it all that we need? Or do I forget something?
What will be checks under this point?

Thanks a lot for your help!

Dear ranchers,

i have some doubt about version.txt document. I am not sure, if this correct to have this file with following context?

java version "1.4.2_10" System: Microsoft Windows XP Home Edition Version 2002 Service Pack 1 Computer: Mobile Intel(R) Pentium(R) 4 CPU 3.06GHz 1,00 GB RAM

could you correct me?

Thanks a lot for your help!

Hello all,

in some of the Data methods, I check if the current record locked or not. For this case I have defined a method, that return true, if the record is locked, otherwise false.
private boolean isRecordLocked(int recNo, long cookie) { Integer recNoInt = new Integer(recNo); Long lockCookie = new Long(cookie); synchronized (lockedRecords) { if (lockedRecords.containsKey(recNoInt) && lockedRecords.get(recNoInt).equals(lockCookie)) { return true; } } return false; }
But I am not sure, should I call the lockedRecords.notifyAll() at the end of this method?

I call lockedRecords.notifyAll() only in the unlock method, to notify that the current record was unlocked. But what about if this method will be called in the delete method or in the update? Is it correct not to call lockedRecords.notifyAll() in this method?

Can you help me?
[ January 06, 2006: Message edited by: Elena Taube ]

Hello everyone,

do you check in the unlock method, if the current record is deleted or not?

My unlock method looks like:

// checks if the record exist in the database
// checks if the record is locked
synchronize block {
// remove locks
}

I have a doubt about the check if the record is deleted or not in the unlock method.
But I am not sure, why the RecordNotFoundException should be thrown. Should it be thrown if the record is deleted in the database or if the record does not exist in the array where I save the record number with the lock cookie?

Thanks a lot for your help!