抽象工厂
在本例中，按钮和复选框将被作为产品。它们有两个变体：macOS 版和 Windows 版。
抽象工厂定义了用于创建按钮和复选框的接口。而两个具体工厂都会返回同一变体的两个产品。
客户端代码使用抽象接口与工厂和产品进行交互。同样的代码能与依赖于不同工厂对象类型的多种产品变体进行交互。
buttons: 第一个产品层次结构
buttons/Button.java
代码语言：javascript复制package refactoring_guru.abstract_factory.example.buttons;
/**
* Abstract Factory assumes that you have several families of products,
* structured into separate class hierarchies (Button/Checkbox). All products of
* the same family have the common interface.
*
* This is the common interface for buttons family.
*/
public interface Button {
void paint();
}buttons/MacOSButton.java
代码语言：javascript复制package refactoring_guru.abstract_factory.example.buttons;
/**
* All products families have the same varieties (MacOS/Windows).
*
* This is a MacOS variant of a button.
*/
public class MacOSButton implements Button {
@Override
public void paint() {
System.out.println("You have created MacOSButton.");
}
}buttons/WindowsButton.java
代码语言：javascript复制package refactoring_guru.abstract_factory.example.buttons;
/**
* All products families have the same varieties (MacOS/Windows).
*
* This is another variant of a button.
*/
public class WindowsButton implements Button {
@Override
public void paint() {
System.out.println("You have created WindowsButton.");
}
}checkboxes: 第二个产品层次结构
checkboxes/Checkbox.java
代码语言：javascript复制package refactoring_guru.abstract_factory.example.checkboxes;
/**
* Checkboxes is the second product family. It has the same variants as buttons.
*/
public interface Checkbox {
void paint();
}checkboxes/MacOSCheckbox.java
代码语言：javascript复制package refactoring_guru.abstract_factory.example.checkboxes;
/**
* All products families have the same varieties (MacOS/Windows).
*
* This is a variant of a checkbox.
*/
public class MacOSCheckbox implements Checkbox {
@Override
public void paint() {
System.out.println("You have created MacOSCheckbox.");
}
}checkboxes/WindowsCheckbox.java
代码语言：javascript复制package refactoring_guru.abstract_factory.example.checkboxes;
/**
* All products families have the same varieties (MacOS/Windows).
*
* This is another variant of a checkbox.
*/
public class WindowsCheckbox implements Checkbox {
@Override
public void paint() {
System.out.println("You have created WindowsCheckbox.");
}
}factories
factories/GUIFactory.java: 抽象工厂
代码语言：javascript复制package refactoring_guru.abstract_factory.example.factories;
import refactoring_guru.abstract_factory.example.buttons.Button;
import refactoring_guru.abstract_factory.example.checkboxes.Checkbox;
/**
* Abstract factory knows about all (abstract) product types.
*/
public interface GUIFactory {
Button createButton();
Checkbox createCheckbox();
}factories/MacOSFactory.java: 具体工厂（ macOS）
代码语言：javascript复制package refactoring_guru.abstract_factory.example.factories;
import refactoring_guru.abstract_factory.example.buttons.Button;
import refactoring_guru.abstract_factory.example.buttons.MacOSButton;
import refactoring_guru.abstract_factory.example.checkboxes.Checkbox;
import refactoring_guru.abstract_factory.example.checkboxes.MacOSCheckbox;
/**
* Each concrete factory extends basic factory and responsible for creating
* products of a single variety.
*/
public class MacOSFactory implements GUIFactory {
@Override
public Button createButton() {
return new MacOSButton();
}
@Override
public Checkbox createCheckbox() {
return new MacOSCheckbox();
}
}factories/WindowsFactory.java: 具体工厂（Windows）
代码语言：javascript复制package refactoring_guru.abstract_factory.example.factories;
import refactoring_guru.abstract_factory.example.buttons.Button;
import refactoring_guru.abstract_factory.example.buttons.WindowsButton;
import refactoring_guru.abstract_factory.example.checkboxes.Checkbox;
import refactoring_guru.abstract_factory.example.checkboxes.WindowsCheckbox;
/**
* Each concrete factory extends basic factory and responsible for creating
* products of a single variety.
*/
public class WindowsFactory implements GUIFactory {
@Override
public Button createButton() {
return new WindowsButton();
}
@Override
public Checkbox createCheckbox() {
return new WindowsCheckbox();
}
}app
app/Application.java: 客户端代码
代码语言：javascript复制package refactoring_guru.abstract_factory.example.app;
import refactoring_guru.abstract_factory.example.buttons.Button;
import refactoring_guru.abstract_factory.example.checkboxes.Checkbox;
import refactoring_guru.abstract_factory.example.factories.GUIFactory;
/**
* Factory users don't care which concrete factory they use since they work with
* factories and products through abstract interfaces.
*/
public class Application {
private Button button;
private Checkbox checkbox;
public Application(GUIFactory factory) {
button = factory.createButton();
checkbox = factory.createCheckbox();
}
public void paint() {
button.paint();
checkbox.paint();
}
}Demo.java: 程序配置
代码语言：javascript复制package refactoring_guru.abstract_factory.example;
import refactoring_guru.abstract_factory.example.app.Application;
import refactoring_guru.abstract_factory.example.factories.GUIFactory;
import refactoring_guru.abstract_factory.example.factories.MacOSFactory;
import refactoring_guru.abstract_factory.example.factories.WindowsFactory;
/**
* Demo class. Everything comes together here.
*/
public class Demo {
/**
* Application picks the factory type and creates it in run time (usually at
* initialization stage), depending on the configuration or environment
* variables.
*/
private static Application configureApplication() {
Application app;
GUIFactory factory;
String osName = System.getProperty("os.name").toLowerCase();
if (osName.contains("mac")) {
factory = new MacOSFactory();
} else {
factory = new WindowsFactory();
}
app = new Application(factory);
return app;
}
public static void main(String[] args) {
Application app = configureApplication();
app.paint();
}
}OutputDemo.txt: 执行结果
代码语言：javascript复制You create WindowsButton.
You created WindowsCheckbox.
