Learning Java

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. If you go with the default options, however, 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 two-dimensional 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", ...