Learning Java, 4th Edition

Tables

Tables present information in orderly rows and columns. This is useful for presenting financial figures or representing data from a relational database. Like trees, tables in Swing are incredibly powerful and customizable. If you go with the default options, they’re also pretty easy to use.

The JTable class represents a visual table component. A JTable is based on a TableModel, one of a dozen or so supporting interfaces and classes in the javax.swing.table package.

A First Stab: Freeloading

JTable has one constructor that creates a default table model for you from arrays of data. You just need to supply it with the names of your column headers and a 2D array of Objects representing the table’s data. The first index selects the table’s row; the second index selects the column. The following example shows how easy it is to get going with tables using this constructor:

    //file: DullShipTable.java
    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    import javax.swing.table.*;

    public class DullShipTable {
      public static void main(String[] args) {
        // create some tabular data
        String[] headings =
          new String[] {"Number", "Hot?", "Origin",
                        "Destination", "Ship Date", "Weight" };
        Object[][] data = new Object[][] {
          { "100420", Boolean.FALSE, "Des Moines IA", "Spokane WA",
              "02/06/2000", new Float(450) },
          { "202174", Boolean.TRUE, "Basking Ridge NJ", "Princeton NJ",
              "05/20/2000", new Float(1250) },
          { "450877", Boolean.TRUE, "St. Paul MN", "Austin TX",
              "03/20/2000", new Float ...