Re: records in jtable
Navnath Gadakh wrote:
how to delete selected rows from jtable and mysql table too??
Do you mean 'JTable', as in 'javax.swing.JTable'?
Do you mean 'MySQL'?
plz help
Sorry, "plz"?
In general terms, you need three cooperating components, a GUI widget
such as your 'JTable', a data model, and a controller or decision-maker.
Call the model the "model", the widget the "view", and the controller the
"controller". These are the "M", "V" and "C", respectively of the "MVC"
architecture.
Look all these terms up, btw.
Now, the model isn't just your database table. It's an *object* model that
is backed up by persistent storage. That means you have two layers - an
in-memory object model and a MySQL database model.
The "model" of MVC is your in-memory object model, more or less. It's
not really the persistent storage - that's a separate layer.
Your view does not tell the model what to do directly. It reports things
to the controller, and the controller dispatches commands to the model.
So if your view calls for a model change, like "delete this row from the
widget", it tells the controller, such as through an 'EventListener'.
The controller looks at the view's event and determines the object that
corresponds to the widget's notification. It then goes to the in-memory
model and says, "Remove this object from the model."
The model component is responsible to clean itself up as needed to
satisfy the request. Unlike all GUI action, this clean-up needs to occur
in a worker thread separate from the EDT (Event Dispatch Thread). You
use a 'SwingWorker' to accomplish that part.
http://docs.oracle.com/javase/7/docs/api/javax/swing/SwingWorker.html
Look all these terms up, btw.
It's the model that determines what, if any, changes need to happen in the
persistent store. If it receives a "Delete object X" command, for example, it
lets the persistent store (the database) know to delete everything relevant to
the disappearance of that object.
The model does this independently of the view, at the direction of the
controller.
Conversely if an external event changes the model, the next time the view goes
to display some information it retrieves it from the now-updated in-memory
model.
Read the Oracle Swing tutorial for initial guidance on how to do the actual coding.
http://docs.oracle.com/javase/tutorial/ui/index.html
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Lew