ChunYong Guan

I registered the SCJD over 1 year ago , I passed it after all.
Here are my results :

General Considerations (maximum = 100): 100
Documentation (maximum = 70) : 70
O-O Design (maximum = 30) : 30
GUI (maximum = 40) : 37
Locking (maximum = 80) : 80
Data store (maximum = 40) : 40
Network server (maximum = 40) : 40
-------------------------
score: 397

I am pleased but surprised for my score.
This certificate proved that:
1.My Eglish is not too bad
2.My java technology is not too bad .
3.Proper confidence is helpful.

Thanks for the great discussions and I wish all the best to each of you.
Especially, thanks my net firend Jack Horner.

Regards,
Guan

[ July 10, 2007: Message edited by: ChunYong Guan ]
[ July 11, 2007: Message edited by: ChunYong Guan ]

Thanks Hatim ,Andrew .
The factory disign is perfect .I like it!
I know what shall I do now!

Thanks a lot,Andrew.
what I designed above is indeed a overlap.It does a wrong way.

So,I do as follow
public class DBAccessFactory{ private DBAccess local; private DBACCessRemote remote; public DBAccessFactory(){ //accoridng the mode ,initializes one of the member varibles if (standalon){ local = .... } else { remote = ... } } public long lock(long recNo){ if (standalon){ return local.lock(recNo); } else { return remote.lock(recNo); } } public void update(long recNo){ if (standalon){ local.update(recNo); } else { remote.update(recNo); } } }
So,In my GUI client ,just need a reference of DBAccessFactory.Is this OK ?
by the way ,I think it has too many if/else clauses in this design.Would someboby give me some advice ?
Thanks and Thanks!

HI,Andrew !
Would you please have a look the question above?(the previous reply of me)
Thanks!

Thanks Thanks ,Andrew .
I understand it through your explain .
I have taken the wrong concept about RMI for 2 years.
So , I think about another question :
interface DataAccess{ longlock(long recNo) ; } //my remote interface interface DataAccessRemote{ long lock(long recNo) throws RemoteException; } //[B]I am hesitating to design this adapter [/B] class DataAccessAdapter implements DataAccess,DataAccessRemote{ longlock(long recNo){ //do something... } }

Can I use such a DataAccessAdapter ?
The client GUI use a DataAccessAdapter's reference to deal with the data(whatever the client GUI is local or remote ,just a DataAccessAdapter's reference.)
If it violates the following rules?

Non-Networked Mode
...
The operating mode is selected using the single command line argument that is permitted. Architecturally, this mode must use the database and GUI from the networked form, but must not use the network server code at all.

[ August 21, 2005: Message edited by: ChunYong Guan ]
[ August 21, 2005: Message edited by: ChunYong Guan ]

I do it as following:

static final short LIVE_RECORD=0x0000; static final short DELETED_RECORD=0x8000; //in delete method .... db.writeShort(DELETED_RECORD); ....
I think a deleted flag always holds 2 bytes.

Samuel,thanks you very much!Yesterday I read the 'Java tutorial'.
Just as you said! I am so careless ,the implementation class of sample codes never throws the RemoteException ,too.
Thanks again.
But I want to ask:
never concern with the RemoteException and then I never throw the RemoteException. so,The RemoteException is a redundant Exception??
If not ,who uses it and who generates it ?

Hello ,every one!Please give me some advice
Assume that :
//The remote interface public interface DataAccessRemote extends Remote{ void update() [B]throws RemoteException[/B]; } //Implements the DataAccessRemote public class DataAccessRemoteImpl implements DataAccessRemote { public void update(){ //do something... } }
the class DataAccessRemote doesn't throw the RemoteException which defines in the DataAccessRemote interface.
Is it illegal "Does it voilate the RMI rules?
But in myself test application,the code above runned happlily!
Can Someone tell detailedly what's wrong with me ??
Thanks very much.
Regards!

Non-Networked Mode
The program must be able to work in a non-networked mode. In this mode, the database and GUI must run in the same VM and must perform no networking, must not use loopback networking, and must not involve the serialization of any objects when communicating between the GUI and database elements.
The operating mode is selected using the single command line argument that is permitted.
Architecturally, this mode must use the database and GUI from the networked form, but must not use the network server code at all.

Since it's a Non-Networked Mode,why they say "Architecturally, this mode must use the database and GUI from the networked form"?
I can't understand.Please give me some explain.Thanks a lot!
(This is my first topic. )