Re: display a TableModel as a JTable

Mark Space <>
Thu, 03 Jul 2008 08:16:41 -0700
thufir wrote:

From the view, how do I make the JTable synchronize with the MyTableModel
instance? A listener of some sort?

First, I think I'd keep anything which has a DB connection away from
Swing. This feels like mixing layers. I'd invent a bean that contained
the actual data, then compose the Swing table model with that bean.

Also, the static fields in MyTableModel smell bad to me.

public class MyJFrame extends JFrame

   private MyTableModel tableModel;
   private JTable viewTable;

   public MyJFrame( MyBean b ) {
     tableModel = new MyTableModel( b ); // Make table model with data
     viewTable = new JTable( tableModel );
     // ... etc. finish JFrame here...

   public static main( String ... args ) {
     // Set up database connection and query...

     ResultSet rs = //...

     MyBean bean = new MyBean( rs ); // build bean from result set
     new MyJFrame( bean ).setVisible( true ); // show the result


class MyTableModel extends AbstractTableModel {

   private MyBean data;

   public MyTableModel( MyBean b ) {
     data = b.clone(); // defensive copy
   // Other methods pretty much as you had them...


// MyBean is "whatever" ... just some data with getters and setters.

So after sketching out the program above, I found that my
"synchronization" came from making a defensive copy. So I avoid any
actual synchronization. This seems like the best way, as a general
case. If you could produce something that's closer to your actual code
or explain why you think you need synchronization, we might be able to
help with some specifics.

Listeners in Swing run on the EDT, so there's no need to synchronize
with any Swing internal data (like models like AbstractTableModel). The
EDT is of course not synchronized with any events external to Swing, so
you have to deal with those yourself. It's this latter case -- events
external to Swing -- that I don't feel like I have enough information on.

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