How to set a different look and feels to swing components in Java?

The Java Swing allows us to customize the GUI by changing the look and feel(L&F). The look defines the general appearance of components and the feel defines their behavior. L&Fs are subclasses of the LookAndFeel class and each L&F is identified by its fully qualified class name. By default, the L&F is set to the Swing L&F ( Metal L&F)

To set the L&F programmatically, we can call the method setLookAndFeel () of the UIManager class. The call to setLookAndFeel must be done before instantiating any Java Swing class, otherwise, the default Swing L&F will be loaded.

Syntax

public static void setLookAndFeel(LookAndFeel newLookAndFeel) throws UnsupportedLookAndFeelException

Example

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class LookAndFeelTest extends JFrame implements ActionListener {
   private JRadioButton windows, metal, motif, ;
   private ButtonGroup bg;
   public LookAndFeelTest() {
      setTitle("Look And Feels");
      windows = new JRadioButton("Windows");
      windows.addActionListener(this);
      metal = new JRadioButton("Metal");
      metal.addActionListener(this);
      motif = new JRadioButton("Motif");
      motif.addActionListener(this);
      bg = new ButtonGroup();
      bg.add(windows);
      bg.add(metal);
      bg.add(motif);
      setLayout(new FlowLayout());
      add(windows);
      add(metal);
      add(motif);
      setSize(400, 300);
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      setLocationRelativeTo(null);
      setVisible(true);
   }
   @Override
   public void actionPerformed(ActionEvent ae) {
      String LAF;
      if(ae.getSource() == windows)
         LAF = "com.sun.java.swing.plaf.windows.WindowsLookAndFeel";
      else if(ae.getSource() == metal)
         LAF = "javax.swing.plaf.metal.MetalLookAndFeel";
      else
         LAF = "com.sun.java.swing.plaf.motif.MotifLookAndFeel";
      try {
         UIManager.setLookAndFeel(LAF);
         SwingUtilities.updateComponentTreeUI(this);
      } catch (Exception e) {
         System.out.println("Error setting the LAF..." + e);
      }
   }
   public static void main(String args[]) {
      new LookAndFeelTest();
   }
}

Output