Java tutorial
/* * Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002. * All rights reserved. Software written by Ian F. Darwin and others. * $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $ * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * Java, the Duke mascot, and all variants of Sun's Java "steaming coffee * cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's, * pioneering role in inventing and promulgating (and standardizing) the Java * language and environment is gratefully acknowledged. * * The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for * inventing predecessor languages C and C++ is also gratefully acknowledged. */ import java.awt.BorderLayout; import java.awt.Container; import java.awt.GridLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.ItemEvent; import java.awt.event.ItemListener; import java.util.Enumeration; import java.util.HashMap; import javax.comm.CommPortIdentifier; import javax.comm.SerialPort; import javax.swing.JButton; import javax.swing.JComboBox; import javax.swing.JDialog; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; /** * Choose a port, any port! * * Java Communications is a "standard extention" and must be downloaded and * installed separately from the JDK before you can even compile this program. * * @author Ian F. Darwin, http://www.darwinsys.com/ * @version $Id: PortChooser.java,v 1.9 2004/04/11 23:50:40 ian Exp $ */ public class PortChooser extends JDialog implements ItemListener { /** A mapping from names to CommPortIdentifiers. */ protected HashMap map = new HashMap(); /** The name of the choice the user made. */ protected String selectedPortName; /** The CommPortIdentifier the user chose. */ protected CommPortIdentifier selectedPortIdentifier; /** The JComboBox for serial ports */ protected JComboBox serialPortsChoice; /** The JComboBox for parallel ports */ protected JComboBox parallelPortsChoice; /** The JComboBox for anything else */ protected JComboBox other; /** The SerialPort object */ protected SerialPort ttya; /** To display the chosen */ protected JLabel choice; /** Padding in the GUI */ protected final int PAD = 5; /** * This will be called from either of the JComboBoxen when the user selects * any given item. */ public void itemStateChanged(ItemEvent e) { // Get the name selectedPortName = (String) ((JComboBox) e.getSource()).getSelectedItem(); // Get the given CommPortIdentifier selectedPortIdentifier = (CommPortIdentifier) map.get(selectedPortName); // Display the name. choice.setText(selectedPortName); } /* The public "getter" to retrieve the chosen port by name. */ public String getSelectedName() { return selectedPortName; } /* The public "getter" to retrieve the selection by CommPortIdentifier. */ public CommPortIdentifier getSelectedIdentifier() { return selectedPortIdentifier; } /** A test program to show up this chooser. */ public static void main(String[] ap) { PortChooser c = new PortChooser(null); c.setVisible(true); // blocking wait System.out.println("You chose " + c.getSelectedName() + " (known by " + c.getSelectedIdentifier() + ")."); System.exit(0); } /** * Construct a PortChooser --make the GUI and populate the ComboBoxes. */ public PortChooser(JFrame parent) { super(parent, "Port Chooser", true); makeGUI(); populate(); finishGUI(); } /** * Build the GUI. You can ignore this for now if you have not yet worked * through the GUI chapter. Your mileage may vary. */ protected void makeGUI() { Container cp = getContentPane(); JPanel centerPanel = new JPanel(); cp.add(BorderLayout.CENTER, centerPanel); centerPanel.setLayout(new GridLayout(0, 2, PAD, PAD)); centerPanel.add(new JLabel("Serial Ports", JLabel.RIGHT)); serialPortsChoice = new JComboBox(); centerPanel.add(serialPortsChoice); serialPortsChoice.setEnabled(false); centerPanel.add(new JLabel("Parallel Ports", JLabel.RIGHT)); parallelPortsChoice = new JComboBox(); centerPanel.add(parallelPortsChoice); parallelPortsChoice.setEnabled(false); centerPanel.add(new JLabel("Unknown Ports", JLabel.RIGHT)); other = new JComboBox(); centerPanel.add(other); other.setEnabled(false); centerPanel.add(new JLabel("Your choice:", JLabel.RIGHT)); centerPanel.add(choice = new JLabel()); JButton okButton; cp.add(BorderLayout.SOUTH, okButton = new JButton("OK")); okButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { PortChooser.this.dispose(); } }); } /** * Populate the ComboBoxes by asking the Java Communications API what ports * it has. Since the initial information comes from a Properties file, it * may not exactly reflect your hardware. */ protected void populate() { // get list of ports available on this particular computer, // by calling static method in CommPortIdentifier. Enumeration pList = CommPortIdentifier.getPortIdentifiers(); // Process the list, putting serial and parallel into ComboBoxes while (pList.hasMoreElements()) { CommPortIdentifier cpi = (CommPortIdentifier) pList.nextElement(); // System.out.println("Port " + cpi.getName()); map.put(cpi.getName(), cpi); if (cpi.getPortType() == CommPortIdentifier.PORT_SERIAL) { serialPortsChoice.setEnabled(true); serialPortsChoice.addItem(cpi.getName()); } else if (cpi.getPortType() == CommPortIdentifier.PORT_PARALLEL) { parallelPortsChoice.setEnabled(true); parallelPortsChoice.addItem(cpi.getName()); } else { other.setEnabled(true); other.addItem(cpi.getName()); } } serialPortsChoice.setSelectedIndex(-1); parallelPortsChoice.setSelectedIndex(-1); } protected void finishGUI() { serialPortsChoice.addItemListener(this); parallelPortsChoice.addItemListener(this); other.addItemListener(this); pack(); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } }