The Graphical User Interfaces - SCJD Exam with J2SE 5 - page 259

Tip The preceding DVDTableModel has the capability to convert DVD model objects one at a time, but
sometimes it is more convenient to provide a method that will convert entire collections of model objects.
That way, a search method could use a single call to convert its entire set of search results.

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Using the TableModel with a JTable
Once a TableModel has been implemented, using it with a JTable is a simple task. A TableModel
may be specified in the constructor of a JTable object. For example, the following snippet will
create a new JTable using the DVDTableModel that was described in the previous section:

JTable table = new JTable (new DVDTableModel ());

The preceding statement will create a JTable using a DVDTableModel , but the table display
will be empty, since no data is contained in the specified DVDTableModel instance.

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Note A JTable instance can have its internal table model modified after it is instantiated. The setModel
method updates a JTable 's internal TableModel member and therefore updates the data the JTable
displays. Data can also be added to a JTable 's TableModel reference by calling the method getModel
method on a JTable instance. In our case, this method can be called to get a reference to the JTable 's
internal DVDTableModel reference. Then the method addRecord can be called to add a row to a JTable .

Because alterations to a JTable 's TableModel translates into an updated View, the client
must be set up to take advantage of this schema. The MainWindow class contains the private
member

private DVDTableModel tableData;

This data member will always hold the main JTable 's TableModel . Because all data trans-
fer between the View and the Controller is done via a DVDTableModel object, this member is
always updated to reflect changes to the database's state.
Once the database has been updated or queried, the resulting table model is placed into
the tableData member. After calling the Controller, the MainWindow class calls its internal pri-
vate method setupTable . This method contains the statements in Listing 8-17.

Listing 8-17. The setupTable Method

private void setupTable() {
// Preserve the previous selection
int index = mainTable.getSelectedRow();
String prevSelected = (index >= 0)
? (String) mainTable.getValueAt(index, 0)
: "";