LookAndFeel changing program will not work?

[Laurence Turpin]

Hello,
I am running Java 6 on a Windows 7 PC.
I am using Eclipse Indigo to run my program.
My program has 2 files:
ToolbarFrame1.java
LnFListener.java

The files compile ok.
When run and I try to change the look and feel I get the following errors
-------------------------------------------------------------------------------------------
LookAndFeel class not found: com.apple.mrj.swing.MacLookAndFeel
LookAndFeel class not found: com.sun.java.swing.plaf.motif.Motif.MotifLookAndFeel
LookAndFeel class not found: com.sun.java.swing.plaf.windows.WindowsLookAndFeel

------------------------------------------------------------------------------------------

Below are the contents of the two files.

--------------------------------------------------------------------------------
ToolBarFrame1.java
----------------------------------------------------------------------------------------

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

public class ToolbarFrame1 extends Frame{
	
	JButton cutButton, copyButton, pasteButton;
	JButton javaButton, macButton, motifButton, winButton;
	public ToolbarFrame1() {
		super("Toolbar Example (Swing)");
		setSize(450, 250);
		addWindowListener(new WindowAdapter() {
			public void windowClosing(WindowEvent e) {
				System.exit(0);
			}
		});
	ActionListener printListener = new ActionListener() {
		public void actionPerformed(ActionEvent ae) {
			System.out.println(ae.getActionCommand());
		}
	};
	
	JPanel toolbar = new JPanel();
	toolbar.setLayout(new FlowLayout(FlowLayout.LEFT));
	
	cutButton = new JButton("Cut");
	cutButton.addActionListener(printListener);
	toolbar.add(cutButton);
	
	copyButton  = new JButton("Copy");
	copyButton.addActionListener(printListener);
	toolbar.add(copyButton);
	
	pasteButton  = new JButton("Paste");
	pasteButton.addActionListener(printListener);
	toolbar.add(pasteButton);
	
	add(toolbar, BorderLayout.NORTH);
	
	JPanel lnfPanel = new JPanel();
	LnFListener lnfListener = new LnFListener(this);
	macButton = new JButton("Mac");
	macButton.addActionListener(lnfListener);
	lnfPanel.add(macButton);
	javaButton = new JButton("Metal");
	javaButton.addActionListener(lnfListener);
	lnfPanel.add(javaButton);
	motifButton = new JButton("Motif");
	motifButton.addActionListener(lnfListener);
	lnfPanel.add(motifButton);
	winButton = new JButton("Windows");
	winButton.addActionListener(lnfListener);
	lnfPanel.add(winButton);
	add(lnfPanel, BorderLayout.SOUTH);
	}
	
	public static void main(String args[]) {
		ToolbarFrame1 tf1 = new ToolbarFrame1();
		tf1.setVisible(true);
	}
}

------------------------------------------------------------------------------
LnFListener. java
-------------------------------------------------------------------------------

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

public class LnFListener implements ActionListener {
	Frame frame;
	
	public LnFListener(Frame f) {
		frame = f;
	}
	
	public void actionPerformed(ActionEvent e) {
		String lnfName = null;
		if (e.getActionCommand().equals("Mac")) {
			lnfName = "com.apple.mrj.swing.MacLookAndFeel";
		} else if (e.getActionCommand().equals("Metal")) {
			lnfName = "javax.swing.plaf.metal.MetalLookAndFeel";
		} else if (e.getActionCommand().equals("Motif")) {
			lnfName = "com.sun.java.swing.plaf.motif.Motif.MotifLookAndFeel";
		} else if (e.getActionCommand().equals("Windows")) {
			lnfName = "com.sun.java.swing.plaf.windows.WindowsLookAndFeel";
		} else {
			System.err.println("Unrecognized L&F request action:" + e.getActionCommand());
			return;
		}
		try {
			UIManager.setLookAndFeel(lnfName);
			SwingUtilities.updateComponentTreeUI(frame);
		}
		catch (UnsupportedLookAndFeelException ex1) {
			System.err.println("Unsupported LookAndFeel: " + lnfName);
		}
		catch (ClassNotFoundException ex2) {
			System.err.println("LookAndFeel class not found: " + lnfName);
		}
		catch (InstantiationException ex3) {
			System.err.println("Could not load LookAndFeel: " + lnfName);
		}
		catch (IllegalAccessException ex4) {
			System.err.println("Cannot use LookAndFeel: " + lnfName);
		}
	}

}

I would be grateful for any helpful suggestions.

[Jesper de Jong]

Welcome to the Ranch!

The errors mean that the look & feel classes that you are trying to use do not exist on your system.

I'm not surprised that "com.apple.mrj.swing.MacLookAndFeel" does not exist, because you're running this on a Windows 7 system and not on an Apple Mac.

Note that class UIManager has a method named getInstalledLookAndFeels() that gives you information about what look & feels are available on your system. You could use that to check which ones you can use, instead of using hard-coded names of look & feels that apparently don't exist on your system.

[Laurence Turpin]

Thank you for your reply.
You are right about the mac LookAndFeel not working on windows.
I changed the mac LookAndFeel to nimbus
I also made a mistake with the motif LookAndFeel
Instead of :
com.sun.java.swing.plaf.motif.Motif.MotifLookAndFeel
It should be:
com.sun.java.swing.plaf.motif.MotifLookAndFeel
Now that I have made those changes it now all works.

Thank you again for your help

[Darryl Burke]

Laurence Turpin wrote:Instead of :
com.sun.java.swing.plaf.motif.Motif.MotifLookAndFeel
It should be:
com.sun.java.swing.plaf.motif.MotifLookAndFeel

You shouldn't be using com.sun.*... classes at all, as they are subject to change or removal. Jesper already told you how to get the list of installed LaFs.