CelsiusConverter.java

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package jpl.test;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class CelsiusConverter implements ActionListener {
        JFrame          converterFrame;
        JPanel          converterPanel;
        JTextField      tempCelsius;
        JLabel          celsiusLabel, fahrenheitLabel;
        JButton         convertTemp;
        public CelsiusConverter() { // initially locate the window at top-left of desktop
                this(0, 0);
        }
        public CelsiusConverter(int left, int top) { // initially locate the window at top-left of desktop
                // create and set up the window
                converterFrame = new JFrame("Convert Celsius to Fahrenheit");
                converterFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                converterFrame.setSize(new Dimension(120, 40));
                converterFrame.setLocation(left, top);
                // create and set up the panel
                converterPanel = new JPanel(new GridLayout(2, 2));
                // create widgets
                tempCelsius = new JTextField(2);
                celsiusLabel = new JLabel("Celsius", SwingConstants.LEFT);
                celsiusLabel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
                //
                convertTemp = new JButton("Convert");
                fahrenheitLabel = new JLabel("Fahrenheit", SwingConstants.LEFT);
                // listen to events from the Convert button
                convertTemp.addActionListener(this);
                // add the widgets to the container
                converterPanel.add(tempCelsius);
                converterPanel.add(celsiusLabel);
                converterPanel.add(convertTemp);
                converterPanel.add(fahrenheitLabel);
                fahrenheitLabel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
                converterFrame.getRootPane().setDefaultButton(convertTemp); // make "convert" the window's default button
                // add the panel to the window
                converterFrame.getContentPane().add(converterPanel, BorderLayout.CENTER);
                // display the window
                converterFrame.pack();
                converterFrame.setVisible(true);
        }
        public void actionPerformed(ActionEvent event) {
                // parse degrees Celsius as a double
                double tC = (Double.parseDouble(tempCelsius.getText()));
                //
                // convert to Fahrenheit (in Java)
                // int tempFahr = (int) (tC * 1.8 + 32);
                //
                // convert to Fahrenheit (in Prolog, via JPL)
                int tempFahr = ((jpl.Float) jpl.Query.oneSolution("TF is ? * 1.8 + 32", new jpl.Term[] {new jpl.Float(tC)}).get("TF")).intValue();
                //
                // display the result
                fahrenheitLabel.setText(tempFahr + " Fahrenheit");
        }
        public static void spawnGUI(final int left, final int top) {
                // schedule a job for the event-dispatching thread: create and show an instance of this application at (left,top)
                javax.swing.SwingUtilities.invokeLater(new Runnable() {
                        int x = left;
                        int y = top;
                        public void run() {
                                new CelsiusConverter(x, y); // can we be sure this won't be garbage collected?
                        }
                });
        }
        public static void main(String[] args) {
                // just for fun, we ask Prolog to start five instances of this class (at stepped offsets from top-left of display)
                jpl.Query.allSolutions("between(1, 5, N), X is 10*N, Y is 20*N, jpl_call('jpl.test.CelsiusConverter', spawnGUI, [X,Y], _)");
        }
}

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jpl
Author(s): Lorenz Moesenlechner
autogenerated on Fri Jan 11 09:40:29 2013