src/demo/share/jfc/SwingSet2/ListDemo.java - platform/libcore.git - Git at Google

 /*
  *
  * Copyright (c) 2007, 2021, Oracle and/or its affiliates. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  *   - Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  *
  *   - 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.
  *
  *   - Neither the name of Oracle nor the names of its
  *     contributors may be used to endorse or promote products derived
  *     from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
  */

 import javax.swing.AbstractAction;
 import javax.swing.AbstractListModel;
 import javax.swing.Action;
 import javax.swing.Box;
 import javax.swing.BoxLayout;
 import javax.swing.DefaultListCellRenderer;
 import javax.swing.ImageIcon;
 import javax.swing.JCheckBox;
 import javax.swing.JComponent;
 import javax.swing.JLabel;
 import javax.swing.JList;
 import javax.swing.JPanel;
 import javax.swing.JScrollPane;

 import java.awt.BorderLayout;
 import java.awt.Component;
 import java.awt.Insets;
 import java.awt.Rectangle;
 import java.awt.event.ActionEvent;
 import java.awt.event.FocusAdapter;
 import java.awt.event.FocusEvent;
 import java.awt.event.FocusListener;
 import java.util.Vector;

 /**
  * List Demo. This demo shows that it is not
  * always necessary to have an array of objects
  * as big as the size of the list stored.
  *
  * Indeed, in this example, there is no array
  * kept for the list data, rather it is generated
  * on the fly as only those elements are needed.
  *
  * @author Jeff Dinkins
  */
 public class ListDemo extends DemoModule {
     JList<String> list;

     JPanel prefixList;
     JPanel suffixList;

     Action prefixAction;
     Action suffixAction;

     GeneratedListModel listModel;

     Vector<JCheckBox> checkboxes = new Vector<>();

     /**
      * main method allows us to run as a standalone demo.
      */
     public static void main(String[] args) {
         ListDemo demo = new ListDemo(null);
         demo.mainImpl();
     }

     /**
      * ListDemo Constructor
      */
     public ListDemo(SwingSet2 swingset) {
         super(swingset, "ListDemo", "toolbar/JList.gif");

         loadImages();

         JLabel description = new JLabel(getString("ListDemo.description"));
         getDemoPanel().add(description, BorderLayout.NORTH);

         JPanel centerPanel = new JPanel();
         centerPanel.setLayout(new BoxLayout(centerPanel, BoxLayout.X_AXIS));
         centerPanel.add(Box.createRigidArea(HGAP10));
         getDemoPanel().add(centerPanel, BorderLayout.CENTER);

         JPanel listPanel = new JPanel();
         listPanel.setLayout(new BoxLayout(listPanel, BoxLayout.Y_AXIS));
         listPanel.add(Box.createRigidArea(VGAP10));

         centerPanel.add(listPanel);
         centerPanel.add(Box.createRigidArea(HGAP30));

         // Create the list
         list = new JList<>();
         list.setCellRenderer(new CompanyLogoListCellRenderer());
         listModel = new GeneratedListModel(this);
         list.setModel(listModel);

         // Set the preferred row count. This affects the preferredSize
         // of the JList when it's in a scrollpane.
         list.setVisibleRowCount(22);

         // Add list to a scrollpane
         JScrollPane scrollPane = new JScrollPane(list);
         listPanel.add(scrollPane);
         listPanel.add(Box.createRigidArea(VGAP10));

         // Add the control panel (holds the prefix/suffix list and prefix/suffix checkboxes)
         centerPanel.add(createControlPanel());

         // create prefixes and suffixes
         addPrefix("Tera", true);
         addPrefix("Micro", false);
         addPrefix("Southern", false);
         addPrefix("Net", true);
         addPrefix("YoYo", true);
         addPrefix("Northern", false);
         addPrefix("Tele", false);
         addPrefix("Eastern", false);
         addPrefix("Neo", false);
         addPrefix("Digi", false);
         addPrefix("National", false);
         addPrefix("Compu", true);
         addPrefix("Meta", true);
         addPrefix("Info", false);
         addPrefix("Western", false);
         addPrefix("Data", false);
         addPrefix("Atlantic", false);
         addPrefix("Advanced", false);
         addPrefix("Euro", false);
         addPrefix("Pacific", false);
         addPrefix("Mobile", false);
         addPrefix("In", false);
         addPrefix("Computa", false);
         addPrefix("Digital", false);
         addPrefix("Analog", false);

         addSuffix("Tech", true);
         addSuffix("Soft", true);
         addSuffix("Telecom", true);
         addSuffix("Solutions", false);
         addSuffix("Works", true);
         addSuffix("Dyne", false);
         addSuffix("Services", false);
         addSuffix("Vers", false);
         addSuffix("Devices", false);
         addSuffix("Software", false);
         addSuffix("Serv", false);
         addSuffix("Systems", true);
         addSuffix("Dynamics", true);
         addSuffix("Net", false);
         addSuffix("Sys", false);
         addSuffix("Computing", false);
         addSuffix("Scape", false);
         addSuffix("Com", false);
         addSuffix("Ware", false);
         addSuffix("Widgets", false);
         addSuffix("Media", false);
         addSuffix("Computer", false);
         addSuffix("Hardware", false);
         addSuffix("Gizmos", false);
         addSuffix("Concepts", false);
     }

     void updateDragEnabled(boolean dragEnabled) {
         list.setDragEnabled(dragEnabled);
     }

     public JPanel createControlPanel() {
         JPanel controlPanel = new JPanel() {
             Insets insets = new Insets(0, 4, 10, 10);
             public Insets getInsets() {
                 return insets;
             }
         };
         controlPanel.setLayout(new BoxLayout(controlPanel, BoxLayout.X_AXIS));

         JPanel prefixPanel = new JPanel();
         prefixPanel.setLayout(new BoxLayout(prefixPanel, BoxLayout.Y_AXIS));
         prefixPanel.add(new JLabel(getString("ListDemo.prefixes")));

         JPanel suffixPanel = new JPanel();
         suffixPanel.setLayout(new BoxLayout(suffixPanel, BoxLayout.Y_AXIS));
         suffixPanel.add(new JLabel(getString("ListDemo.suffixes")));

         prefixList = new JPanel() {
             Insets insets = new Insets(0, 4, 0, 0);
             public Insets getInsets() {
                 return insets;
             }
         };
         prefixList.setLayout(new BoxLayout(prefixList, BoxLayout.Y_AXIS));
         JScrollPane scrollPane = new JScrollPane(prefixList);
         scrollPane.getVerticalScrollBar().setUnitIncrement(10);
         prefixPanel.add(scrollPane);
         prefixPanel.add(Box.createRigidArea(HGAP10));

         suffixList = new JPanel() {
             Insets insets = new Insets(0, 4, 0, 0);
             public Insets getInsets() {
                 return insets;
             }
         };
         suffixList.setLayout(new BoxLayout(suffixList, BoxLayout.Y_AXIS));
         scrollPane = new JScrollPane(suffixList);
         scrollPane.getVerticalScrollBar().setUnitIncrement(10);
         suffixPanel.add(scrollPane);
         suffixPanel.add(Box.createRigidArea(HGAP10));

         controlPanel.add(prefixPanel);
         controlPanel.add(Box.createRigidArea(HGAP15));
         controlPanel.add(suffixPanel);
         return controlPanel;
     }

     private FocusListener listFocusListener = new FocusAdapter() {
         public void focusGained(FocusEvent e) {
             JComponent c = (JComponent)e.getComponent();
             c.scrollRectToVisible(new Rectangle(0, 0, c.getWidth(), c.getHeight()));
         }
     };

     public void addPrefix(String prefix, boolean selected) {
         if(prefixAction == null) {
             prefixAction = new UpdatePrefixListAction(listModel);
         }
         final JCheckBox cb = (JCheckBox) prefixList.add(new JCheckBox(prefix));
         checkboxes.addElement(cb);
         cb.setSelected(selected);
         cb.addActionListener(prefixAction);
         if(selected) {
             listModel.addPrefix(prefix);
         }
         cb.addFocusListener(listFocusListener);
     }

     public void addSuffix(String suffix, boolean selected) {
         if(suffixAction == null) {
             suffixAction = new UpdateSuffixListAction(listModel);
         }
         final JCheckBox cb = (JCheckBox) suffixList.add(new JCheckBox(suffix));
         checkboxes.addElement(cb);
         cb.setSelected(selected);
         cb.addActionListener(suffixAction);
         if(selected) {
             listModel.addSuffix(suffix);
         }
         cb.addFocusListener(listFocusListener);
     }

     class UpdatePrefixListAction extends AbstractAction {
         GeneratedListModel listModel;
         protected UpdatePrefixListAction(GeneratedListModel listModel) {
             this.listModel = listModel;
         }

         public void actionPerformed(ActionEvent e) {
             JCheckBox cb = (JCheckBox) e.getSource();
             if(cb.isSelected()) {
                 listModel.addPrefix(cb.getText());
             } else {
                 listModel.removePrefix(cb.getText());
             }
         }
     }

     class UpdateSuffixListAction extends AbstractAction {
         GeneratedListModel listModel;
         protected UpdateSuffixListAction(GeneratedListModel listModel) {
             this.listModel = listModel;
         }

         public void actionPerformed(ActionEvent e) {
             JCheckBox cb = (JCheckBox) e.getSource();
             if(cb.isSelected()) {
                 listModel.addSuffix(cb.getText());
             } else {
                 listModel.removeSuffix(cb.getText());
             }
         }
     }


     class GeneratedListModel extends AbstractListModel<String> {
         ListDemo demo;
         Permuter permuter;

         public Vector<String> prefix = new Vector<>();
         public Vector<String> suffix = new Vector<>();

         public GeneratedListModel (ListDemo demo) {
             this.demo = demo;
         }

         private void update() {
             permuter = new Permuter(getSize());
             fireContentsChanged(this, 0, getSize());
         }

         public void addPrefix(String s) {
             if(!prefix.contains(s)) {
                 prefix.addElement(s);
                 update();
             }
         }

         public void removePrefix(String s) {
             prefix.removeElement(s);
             update();
         }

         public void addSuffix(String s) {
             if(!suffix.contains(s)) {
                 suffix.addElement(s);
                 update();
             }
         }

         public void removeSuffix(String s) {
             suffix.removeElement(s);
             update();
         }

         public int getSize() {
             return prefix.size() * suffix.size();
         }

         public String getElementAt(int index) {
             if(permuter == null) {
                 update();
             }
             // morph the index to another int -- this has the benefit of
             // causing the list to look random.
             int j = permuter.map(index);
             int ps = prefix.size();
             int ss = suffix.size();
             return (String) prefix.elementAt(j%ps) + (String) suffix.elementAt((j/ps)%ss);
         }
     }

     ImageIcon[] images = new ImageIcon[7];
     void loadImages() {
             images[0] = createImageIcon("list/red.gif",  getString("ListDemo.red"));
             images[1] = createImageIcon("list/blue.gif",  getString("ListDemo.blue"));
             images[2] = createImageIcon("list/yellow.gif",  getString("ListDemo.yellow"));
             images[3] = createImageIcon("list/green.gif",  getString("ListDemo.green"));
             images[4] = createImageIcon("list/gray.gif",  getString("ListDemo.gray"));
             images[5] = createImageIcon("list/cyan.gif",  getString("ListDemo.cyan"));
             images[6] = createImageIcon("list/magenta.gif",  getString("ListDemo.magenta"));
     }

     class CompanyLogoListCellRenderer extends DefaultListCellRenderer {
        public Component getListCellRendererComponent(
             JList<?> list,
             Object value,
             int index,
             boolean isSelected,
             boolean cellHasFocus)
         {
             Component retValue = super.getListCellRendererComponent(
                 list, value, index, isSelected, cellHasFocus
             );
             setIcon(images[index%7]);
             return retValue;
         }
     }
 }
	/*
	*
	* Copyright (c) 2007, 2021, Oracle and/or its affiliates. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	*
	* - Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	*
	* - 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.
	*
	* - Neither the name of Oracle nor the names of its
	* contributors may be used to endorse or promote products derived
	* from this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
	*/

	import javax.swing.AbstractAction;
	import javax.swing.AbstractListModel;
	import javax.swing.Action;
	import javax.swing.Box;
	import javax.swing.BoxLayout;
	import javax.swing.DefaultListCellRenderer;
	import javax.swing.ImageIcon;
	import javax.swing.JCheckBox;
	import javax.swing.JComponent;
	import javax.swing.JLabel;
	import javax.swing.JList;
	import javax.swing.JPanel;
	import javax.swing.JScrollPane;

	import java.awt.BorderLayout;
	import java.awt.Component;
	import java.awt.Insets;
	import java.awt.Rectangle;
	import java.awt.event.ActionEvent;
	import java.awt.event.FocusAdapter;
	import java.awt.event.FocusEvent;
	import java.awt.event.FocusListener;
	import java.util.Vector;

	/**
	* List Demo. This demo shows that it is not
	* always necessary to have an array of objects
	* as big as the size of the list stored.
	*
	* Indeed, in this example, there is no array
	* kept for the list data, rather it is generated
	* on the fly as only those elements are needed.
	*
	* @author Jeff Dinkins
	*/
	public class ListDemo extends DemoModule {
	JList<String> list;

	JPanel prefixList;
	JPanel suffixList;

	Action prefixAction;
	Action suffixAction;

	GeneratedListModel listModel;

	Vector<JCheckBox> checkboxes = new Vector<>();

	/**
	* main method allows us to run as a standalone demo.
	*/
	public static void main(String[] args) {
	ListDemo demo = new ListDemo(null);
	demo.mainImpl();
	}

	/**
	* ListDemo Constructor
	*/
	public ListDemo(SwingSet2 swingset) {
	super(swingset, "ListDemo", "toolbar/JList.gif");

	loadImages();

	JLabel description = new JLabel(getString("ListDemo.description"));
	getDemoPanel().add(description, BorderLayout.NORTH);

	JPanel centerPanel = new JPanel();
	centerPanel.setLayout(new BoxLayout(centerPanel, BoxLayout.X_AXIS));
	centerPanel.add(Box.createRigidArea(HGAP10));
	getDemoPanel().add(centerPanel, BorderLayout.CENTER);

	JPanel listPanel = new JPanel();
	listPanel.setLayout(new BoxLayout(listPanel, BoxLayout.Y_AXIS));
	listPanel.add(Box.createRigidArea(VGAP10));

	centerPanel.add(listPanel);
	centerPanel.add(Box.createRigidArea(HGAP30));

	// Create the list
	list = new JList<>();
	list.setCellRenderer(new CompanyLogoListCellRenderer());
	listModel = new GeneratedListModel(this);
	list.setModel(listModel);

	// Set the preferred row count. This affects the preferredSize
	// of the JList when it's in a scrollpane.
	list.setVisibleRowCount(22);

	// Add list to a scrollpane
	JScrollPane scrollPane = new JScrollPane(list);
	listPanel.add(scrollPane);
	listPanel.add(Box.createRigidArea(VGAP10));

	// Add the control panel (holds the prefix/suffix list and prefix/suffix checkboxes)
	centerPanel.add(createControlPanel());

	// create prefixes and suffixes
	addPrefix("Tera", true);
	addPrefix("Micro", false);
	addPrefix("Southern", false);
	addPrefix("Net", true);
	addPrefix("YoYo", true);
	addPrefix("Northern", false);
	addPrefix("Tele", false);
	addPrefix("Eastern", false);
	addPrefix("Neo", false);
	addPrefix("Digi", false);
	addPrefix("National", false);
	addPrefix("Compu", true);
	addPrefix("Meta", true);
	addPrefix("Info", false);
	addPrefix("Western", false);
	addPrefix("Data", false);
	addPrefix("Atlantic", false);
	addPrefix("Advanced", false);
	addPrefix("Euro", false);
	addPrefix("Pacific", false);
	addPrefix("Mobile", false);
	addPrefix("In", false);
	addPrefix("Computa", false);
	addPrefix("Digital", false);
	addPrefix("Analog", false);

	addSuffix("Tech", true);
	addSuffix("Soft", true);
	addSuffix("Telecom", true);
	addSuffix("Solutions", false);
	addSuffix("Works", true);
	addSuffix("Dyne", false);
	addSuffix("Services", false);
	addSuffix("Vers", false);
	addSuffix("Devices", false);
	addSuffix("Software", false);
	addSuffix("Serv", false);
	addSuffix("Systems", true);
	addSuffix("Dynamics", true);
	addSuffix("Net", false);
	addSuffix("Sys", false);
	addSuffix("Computing", false);
	addSuffix("Scape", false);
	addSuffix("Com", false);
	addSuffix("Ware", false);
	addSuffix("Widgets", false);
	addSuffix("Media", false);
	addSuffix("Computer", false);
	addSuffix("Hardware", false);
	addSuffix("Gizmos", false);
	addSuffix("Concepts", false);
	}

	void updateDragEnabled(boolean dragEnabled) {
	list.setDragEnabled(dragEnabled);
	}

	public JPanel createControlPanel() {
	JPanel controlPanel = new JPanel() {
	Insets insets = new Insets(0, 4, 10, 10);
	public Insets getInsets() {
	return insets;
	}
	};
	controlPanel.setLayout(new BoxLayout(controlPanel, BoxLayout.X_AXIS));

	JPanel prefixPanel = new JPanel();
	prefixPanel.setLayout(new BoxLayout(prefixPanel, BoxLayout.Y_AXIS));
	prefixPanel.add(new JLabel(getString("ListDemo.prefixes")));

	JPanel suffixPanel = new JPanel();
	suffixPanel.setLayout(new BoxLayout(suffixPanel, BoxLayout.Y_AXIS));
	suffixPanel.add(new JLabel(getString("ListDemo.suffixes")));

	prefixList = new JPanel() {
	Insets insets = new Insets(0, 4, 0, 0);
	public Insets getInsets() {
	return insets;
	}
	};
	prefixList.setLayout(new BoxLayout(prefixList, BoxLayout.Y_AXIS));
	JScrollPane scrollPane = new JScrollPane(prefixList);
	scrollPane.getVerticalScrollBar().setUnitIncrement(10);
	prefixPanel.add(scrollPane);
	prefixPanel.add(Box.createRigidArea(HGAP10));

	suffixList = new JPanel() {
	Insets insets = new Insets(0, 4, 0, 0);
	public Insets getInsets() {
	return insets;
	}
	};
	suffixList.setLayout(new BoxLayout(suffixList, BoxLayout.Y_AXIS));
	scrollPane = new JScrollPane(suffixList);
	scrollPane.getVerticalScrollBar().setUnitIncrement(10);
	suffixPanel.add(scrollPane);
	suffixPanel.add(Box.createRigidArea(HGAP10));

	controlPanel.add(prefixPanel);
	controlPanel.add(Box.createRigidArea(HGAP15));
	controlPanel.add(suffixPanel);
	return controlPanel;
	}

	private FocusListener listFocusListener = new FocusAdapter() {
	public void focusGained(FocusEvent e) {
	JComponent c = (JComponent)e.getComponent();
	c.scrollRectToVisible(new Rectangle(0, 0, c.getWidth(), c.getHeight()));
	}
	};

	public void addPrefix(String prefix, boolean selected) {
	if(prefixAction == null) {
	prefixAction = new UpdatePrefixListAction(listModel);
	}
	final JCheckBox cb = (JCheckBox) prefixList.add(new JCheckBox(prefix));
	checkboxes.addElement(cb);
	cb.setSelected(selected);
	cb.addActionListener(prefixAction);
	if(selected) {
	listModel.addPrefix(prefix);
	}
	cb.addFocusListener(listFocusListener);
	}

	public void addSuffix(String suffix, boolean selected) {
	if(suffixAction == null) {
	suffixAction = new UpdateSuffixListAction(listModel);
	}
	final JCheckBox cb = (JCheckBox) suffixList.add(new JCheckBox(suffix));
	checkboxes.addElement(cb);
	cb.setSelected(selected);
	cb.addActionListener(suffixAction);
	if(selected) {
	listModel.addSuffix(suffix);
	}
	cb.addFocusListener(listFocusListener);
	}

	class UpdatePrefixListAction extends AbstractAction {
	GeneratedListModel listModel;
	protected UpdatePrefixListAction(GeneratedListModel listModel) {
	this.listModel = listModel;
	}

	public void actionPerformed(ActionEvent e) {
	JCheckBox cb = (JCheckBox) e.getSource();
	if(cb.isSelected()) {
	listModel.addPrefix(cb.getText());
	} else {
	listModel.removePrefix(cb.getText());
	}
	}
	}

	class UpdateSuffixListAction extends AbstractAction {
	GeneratedListModel listModel;
	protected UpdateSuffixListAction(GeneratedListModel listModel) {
	this.listModel = listModel;
	}

	public void actionPerformed(ActionEvent e) {
	JCheckBox cb = (JCheckBox) e.getSource();
	if(cb.isSelected()) {
	listModel.addSuffix(cb.getText());
	} else {
	listModel.removeSuffix(cb.getText());
	}
	}
	}


	class GeneratedListModel extends AbstractListModel<String> {
	ListDemo demo;
	Permuter permuter;

	public Vector<String> prefix = new Vector<>();
	public Vector<String> suffix = new Vector<>();

	public GeneratedListModel (ListDemo demo) {
	this.demo = demo;
	}

	private void update() {
	permuter = new Permuter(getSize());
	fireContentsChanged(this, 0, getSize());
	}

	public void addPrefix(String s) {
	if(!prefix.contains(s)) {
	prefix.addElement(s);
	update();
	}
	}

	public void removePrefix(String s) {
	prefix.removeElement(s);
	update();
	}

	public void addSuffix(String s) {
	if(!suffix.contains(s)) {
	suffix.addElement(s);
	update();
	}
	}

	public void removeSuffix(String s) {
	suffix.removeElement(s);
	update();
	}

	public int getSize() {
	return prefix.size() * suffix.size();
	}

	public String getElementAt(int index) {
	if(permuter == null) {
	update();
	}
	// morph the index to another int -- this has the benefit of
	// causing the list to look random.
	int j = permuter.map(index);
	int ps = prefix.size();
	int ss = suffix.size();
	return (String) prefix.elementAt(j%ps) + (String) suffix.elementAt((j/ps)%ss);
	}
	}

	ImageIcon[] images = new ImageIcon[7];
	void loadImages() {
	images[0] = createImageIcon("list/red.gif", getString("ListDemo.red"));
	images[1] = createImageIcon("list/blue.gif", getString("ListDemo.blue"));
	images[2] = createImageIcon("list/yellow.gif", getString("ListDemo.yellow"));
	images[3] = createImageIcon("list/green.gif", getString("ListDemo.green"));
	images[4] = createImageIcon("list/gray.gif", getString("ListDemo.gray"));
	images[5] = createImageIcon("list/cyan.gif", getString("ListDemo.cyan"));
	images[6] = createImageIcon("list/magenta.gif", getString("ListDemo.magenta"));
	}

	class CompanyLogoListCellRenderer extends DefaultListCellRenderer {
	public Component getListCellRendererComponent(
	JList<?> list,
	Object value,
	int index,
	boolean isSelected,
	boolean cellHasFocus)
	{
	Component retValue = super.getListCellRendererComponent(
	list, value, index, isSelected, cellHasFocus
	);
	setIcon(images[index%7]);
	return retValue;
	}
	}
	}