设计模式＝＝抽象工厂模式（Abstract Factory）
/* * * 抽象工厂模式（Abstract Factory） * * 针对多个产品等级的情况，而工厂方法模式针对单一产品等级的情况。 */package model;import java.awt.Button;import java.awt.Component;import java.awt.FlowLayout;import java.awt.Frame;import java.awt.TextField;import java.awt.event.WindowAdapter;import java.awt.event.WindowEvent;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JTextField;public class TestAbstractFactory { public static void main(String[] args) { GUIFactory fact = new SwingFactory(); Frame f = fact.getFrame(); Component c1 = fact.getButton(); Component c2 = fact.getTextField(); f.setSize(500, 300); f.setLayout(new FlowLayout()); f.add(c1); f.add(c2); f.setVisible(true); f.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }); }}abstract class GUIFactory { public abstract Component getButton(); public abstract Component getTextField(); public abstract Frame getFrame();}class AWTFactory extends GUIFactory { public Component getButton() { return new Button("AWT Button"); } public Frame getFrame() { return new Frame("AWT Frame"); } public Component getTextField() { return new TextField(20); }}class SwingFactory extends GUIFactory { public Component getButton() { return new JButton("Swing Button"); } public Frame getFrame() { return new JFrame("Swing Frame"); } public Component getTextField() { return new JTextField(20); }}?