/* * A 1.4 application that requires the following files: *   ConversionPanel.java *   ConverterRangeModel.java *   FollowerRangeModel.java *   Unit.java */import javax.swing.*;import javax.swing.event.*;import java.awt.*;import java.awt.event.*;import java.util.*;public class Converter {    ConversionPanel metricPanel, usaPanel;    Unit[] metricDistances = new Unit[3];    Unit[] usaDistances = new Unit[4];    final static boolean MULTICOLORED = false;    //Specify the look and feel to use.  Valid values:    //null (use the default), "Metal", "System", "Motif", "GTK+"    final static String LOOKANDFEEL = null;    ConverterRangeModel dataModel = new ConverterRangeModel();    JPanel mainPane;    /**     * Create the ConversionPanels (one for metric, another for U.S.).     * I used "U.S." because although Imperial and U.S. distance     * measurements are the same, this program could be extended to     * include volume measurements, which aren't the same.     */    public Converter() {        //Create Unit objects for metric distances, and then        //instantiate a ConversionPanel with these Units.        metricDistances[0] = new Unit("Centimeters", 0.01);        metricDistances[1] = new Unit("Meters", 1.0);        metricDistances[2] = new Unit("Kilometers", 1000.0);        metricPanel = new ConversionPanel(this, "Metric System",                                          metricDistances,                                          dataModel);        //Create Unit objects for U.S. distances, and then        //instantiate a ConversionPanel with these Units.        usaDistances[0] = new Unit("Inches", 0.0254);        usaDistances[1] = new Unit("Feet", 0.305);        usaDistances[2] = new Unit("Yards", 0.914);        usaDistances[3] = new Unit("Miles", 1613.0);        usaPanel = new ConversionPanel(this, "U.S. System",                                       usaDistances,                                       new FollowerRangeModel(dataModel));        //Create a JPanel, and add the ConversionPanels to it.        mainPane = new JPanel();        mainPane.setLayout(new BoxLayout(mainPane, BoxLayout.PAGE_AXIS));        if (MULTICOLORED) {            mainPane.setOpaque(true);            mainPane.setBackground(new Color(255, 0, 0));        }        mainPane.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));        mainPane.add(Box.createRigidArea(new Dimension(0, 5)));        mainPane.add(metricPanel);        mainPane.add(Box.createRigidArea(new Dimension(0, 5)));        mainPane.add(usaPanel);        mainPane.add(Box.createGlue());        resetMaxValues(true);    }    public void resetMaxValues(boolean resetCurrentValues) {        double metricMultiplier = metricPanel.getMultiplier();        double usaMultiplier = usaPanel.getMultiplier();        int maximum = ConversionPanel.MAX;        if (metricMultiplier > usaMultiplier) {            maximum = (int)(ConversionPanel.MAX *                      (usaMultiplier/metricMultiplier));        }        dataModel.setMaximum(maximum);        if (resetCurrentValues) {            dataModel.setDoubleValue(maximum);        }    }    private static void initLookAndFeel() {        String lookAndFeel = null;        if (LOOKANDFEEL != null) {            if (LOOKANDFEEL.equals("Metal")) {                lookAndFeel = UIManager.getCrossPlatformLookAndFeelClassName();            } else if (LOOKANDFEEL.equals("System")) {                lookAndFeel = UIManager.getSystemLookAndFeelClassName();            } else if (LOOKANDFEEL.equals("Motif")) {                lookAndFeel = "com.sun.java.swing.plaf.motif.MotifLookAndFeel";            } else if (LOOKANDFEEL.equals("GTK+")) { //new in 1.4.2                lookAndFeel = "com.sun.java.swing.plaf.gtk.GTKLookAndFeel";            } else {                System.err.println("Unexpected value of LOOKANDFEEL specified: "                                   + LOOKANDFEEL);                lookAndFeel = UIManager.getCrossPlatformLookAndFeelClassName();            }            try {                UIManager.setLookAndFeel(lookAndFeel);            } catch (ClassNotFoundException e) {                System.err.println("Couldn't find class for specified look and feel:"                                   + lookAndFeel);                System.err.println("Did you include the L&F library in the class path?");                System.err.println("Using the default look and feel.");            } catch (UnsupportedLookAndFeelException e) {                System.err.println("Can't use the specified look and feel ("                                   + lookAndFeel                                   + ") on this platform.");                System.err.println("Using the default look and feel.");            } catch (Exception e) {                System.err.println("Couldn't get specified look and feel ("                                   + lookAndFeel                                   + "), for some reason.");                System.err.println("Using the default look and feel.");                e.printStackTrace();            }        }    }    /**     * Create the GUI and show it.  For thread safety,     * this method should be invoked from the     * event-dispatching thread.     */    private static void createAndShowGUI() {        //Set the look and feel.        initLookAndFeel();        //Make sure we have nice window decorations.        JFrame.setDefaultLookAndFeelDecorated(true);        //Create and set up the window.        JFrame frame = new JFrame("Converter");        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);        //Create and set up the content pane.        Converter converter = new Converter();        converter.mainPane.setOpaque(true); //content panes must be opaque        frame.setContentPane(converter.mainPane);        //Display the window.        frame.pack();        frame.setVisible(true);    }    public static void main(String[] args) {        //Schedule a job for the event-dispatching thread:        //creating and showing this application's GUI.        javax.swing.SwingUtilities.invokeLater(new Runnable() {            public void run() {                createAndShowGUI();            }        });    }}