Abstract Factory Pattern
Factory
- Abstract Factory
- Abstract Products
Concrete Factories
- Concrete Factory1 - ListFactory
  - Concrete Factory
  - Concrete Products
- Concrete Factory2 - DivFactory
  - Concrete Factory
  - Concrete Products
Client
- 실행 결과
  - Concrete Factory1 - ListFactory
  - Concrete Factory2 - DivFactory

Abstract Factory Pattern

관련 부품을 조합해서 인스턴스 생성

부품의 구체적인 구현에는 주목하지 않고, 인터페이스(API)에 주목.
추상적인 공장(Abstract Factory)에서 추상적인 부품을 조립하고 추상적인 제품을 완성한다.
- 많은 수의 연관된 하위 클래스를 특정 그룹으로 묶어 한번에 교체.
  ex) 특정 라이브러리 배포시 OS별로 지원하는 기능이 다를 때, OS별 기능 변경을 통합적으로 변경.

Architecture, Modeling, Design Pattern, Creational

Factory

Abstract Factory

package factory;

public abstract class Factory {
	public static Factory getFactory(String className) {
		Factory factory = null;
		
		try {
			factory = (Factory) Class.forName(className).newInstance();
		} catch (InstantiationException | IllegalAccessException | ClassNotFoundException e) {
			e.printStackTrace();
		}
		
		return factory;
	}
	
	public abstract LinkItem createLink(String caption, String url);
	public abstract TrayItem createTray(String caption);
	public abstract Page createPage(String caption, String author);
}

Abstract Products

public abstract class Item {
	protected String caption;

	public Item(String caption) {
		super();
		this.caption = caption;
	}
	
	public abstract String makeHTML();
}

package factory;

public abstract class LinkItem extends Item {

	protected String url;
	
	public LinkItem(String caption, String url) {
		super(caption);
		this.url = url;
	}
}

package factory;

import java.util.ArrayList;

public abstract class TrayItem extends Item {

	protected final ArrayList<Item> tray = new ArrayList<>();
	
	public TrayItem(String caption) {
		super(caption);
	}
	
	public void add(Item item) {
		tray.add(item);
	}
}

package factory;

import java.io.BufferedWriter;
import java.io.FileOutputStream;
import java.io.OutputStreamWriter;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;

public abstract class Page {
	protected String title;
	protected String author;
	protected ArrayList<Item> content = new ArrayList<>();
	
	public Page(String title, String author) {
		this.title = title;
		this.author = author;
	}
	
	public void add(Item item) {
		content.add(item);
	}
	
	public void output() {
		System.out.println(this.makeHTML());
		
		try (BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(title + ".html"), StandardCharsets.UTF_8))) {
			bw.write(this.makeHTML());
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	public abstract String makeHTML();
}

Concrete Factories

Concrete Factory1 - ListFactory

Concrete Factory

package listfactory;

import factory.Factory;
import factory.LinkItem;
import factory.Page;
import factory.TrayItem;

public class ListFactory extends Factory {

	@Override
	public LinkItem createLink(String caption, String url) {
		return new ListLink(caption, url);
	}

	@Override
	public TrayItem createTray(String caption) {
		return new ListTray(caption);
	}

	@Override
	public Page createPage(String caption, String author) {
		return new ListPage(caption, author);
	}

}

Concrete Products

package listfactory;

import factory.LinkItem;

public class ListLink extends LinkItem {
	
	public ListLink(String caption, String url) {
		super(caption, url);
	}

	@Override
	public String makeHTML() {
		StringBuilder sb = new StringBuilder();
		sb.append("<li>");
		sb.append("<a href=\"");
		sb.append(url);
		sb.append("\">");
		sb.append(caption);
		sb.append("</a>");
		sb.append("</li>\n");
		
		return sb.toString();
	}

}

package listfactory;

import factory.TrayItem;

public class ListTray extends TrayItem {

	public ListTray(String caption) {
		super(caption);
	}

	@Override
	public String makeHTML() {
		StringBuilder sb = new StringBuilder();
		sb.append("<li>\n");
		sb.append(caption);
		
		sb.append("\n<ul>\n");
		tray.forEach(item -> sb.append(item.makeHTML()));
		sb.append("</ul>\n");
		
		sb.append("</li>");
		
		return sb.toString();
	}
}

package listfactory;

import factory.Page;

public class ListPage extends Page {

	public ListPage(String title, String author) {
		super(title, author);
	}

	@Override
	public String makeHTML() {
		StringBuilder sb = new StringBuilder();
		sb.append("<html>\n");
		sb.append("<head><title>");
		sb.append(title);
		sb.append("</title></head>\n");
		
		sb.append("<body>\n");

		sb.append("<h1>");
		sb.append(title);
		sb.append("</h1>");
		
		sb.append("<ul>\n");
		content.forEach(item -> sb.append(item.makeHTML()));
		sb.append("</ul>\n");
		
		sb.append("<hr>");
		
		sb.append("<footer>");
		sb.append(author);
		sb.append("</footer>");
		
		sb.append("</body>\n</html>");
		
		return sb.toString();
	}

}

Concrete Factory2 - DivFactory

Concrete Factory

package divfactory;

import factory.Factory;
import factory.LinkItem;
import factory.Page;
import factory.TrayItem;

public class DivFactory extends Factory {

	@Override
	public LinkItem createLink(String caption, String url) {
		return new DivLink(caption, url);
	}

	@Override
	public TrayItem createTray(String caption) {
		return new DivTray(caption);
	}

	@Override
	public Page createPage(String caption, String author) {
		return new DivPage(caption, author);
	}

}

Concrete Products

package divfactory;

import factory.LinkItem;

public class DivLink extends LinkItem {

	public DivLink(String caption, String url) {
		super(caption, url);
	}

	@Override
	public String makeHTML() {
		StringBuilder sb = new StringBuilder();
		sb.append("\n<span>");
		sb.append("<a href=\"");
		sb.append(url);
		sb.append("\">");
		sb.append(caption);
		sb.append("</a>");
		sb.append("</span>\n");
		
		return sb.toString();
	}
}

package divfactory;

import factory.TrayItem;

public class DivTray extends TrayItem {

	public DivTray(String caption) {
		super(caption);
	}

	@Override
	public String makeHTML() {
		StringBuilder sb = new StringBuilder();
		sb.append("\n<div style=\"border: 1px solid black; ; margin: 5px; padding: 5px\">");
		
		sb.append("\n<div>");
		sb.append(caption);
		sb.append("</div>\n");
		
		sb.append("\n<div>");
		tray.forEach(item -> sb.append(item.makeHTML()));
		sb.append("</div>\n");
		
		sb.append("</div>\n");
		sb.append("<br>\n");
		
		return sb.toString();
	}

}

package divfactory;

import factory.Page;

public class DivPage extends Page {

	public DivPage(String title, String author) {
		super(title, author);
	}

	@Override
	public String makeHTML() {
		StringBuilder sb = new StringBuilder();
		sb.append("<html>\n");
		sb.append("<head><title>");
		sb.append(title);
		sb.append("</title></head>\n");
		
		sb.append("<body>\n");

		sb.append("<h1>");
		sb.append(title);
		sb.append("</h1>");
		
		sb.append("\n<div>");
		content.forEach(item -> sb.append(item.makeHTML()));
		sb.append("</div>\n");
		
		sb.append("<hr>");
		
		sb.append("<footer>");
		sb.append(author);
		sb.append("</footer>");
		
		sb.append("</body>\n</html>");
		
		return sb.toString();
	}

}

Client

Client는 구체적인 부품, 제품, 공장에 대해 모른다!
- API만 이용! 말그대로 추상적인 공장(Abstract Factory)에서 추상적인 부품을 조립하고 추상적인 제품을 완성한다.

import factory.Factory;
import factory.LinkItem;
import factory.Page;
import factory.TrayItem;

public class Main {
	public static void main(String[] args) {
		operateFactory("listfactory.ListFactory");
		operateFactory("divfactory.DivFactory");
	}
	
	private static void operateFactory(String className) {
		Factory factory = Factory.getFactory(className);
		
		
		LinkItem link_todayHumor = factory.createLink("오늘의 유머", "http://www.todayhumor.co.kr");
		LinkItem link_ruliweb = factory.createLink("루리웹", "http://ruliweb.com/");
		
		TrayItem trary_community = factory.createTray("커뮤니티");
		trary_community.add(link_todayHumor);
		trary_community.add(link_ruliweb);
		
		
		LinkItem link_google = factory.createLink("Google", "http://www.google.com");
		LinkItem link_daum = factory.createLink("Daum", "http://www.daum.net");
		
		LinkItem link_naver = factory.createLink("Naver", "http://www.naver.com");
		LinkItem link_naver_m = factory.createLink("Naver Mobile", "http://m.naver.com");

		
		TrayItem tray_naver = factory.createTray("Naver");
		tray_naver.add(link_naver);
		tray_naver.add(link_naver_m);
		
		TrayItem tray_searchEngine = factory.createTray("검색 엔진");
		tray_searchEngine.add(link_google);
		tray_searchEngine.add(link_daum);
		tray_searchEngine.add(tray_naver);
		
		
		Page page = factory.createPage(className, "By ledyx");
		page.add(trary_community);
		page.add(tray_searchEngine);
		
		page.output();
	}
}

실행 결과

Concrete Factory1 - ListFactory

<html>
<head><title>listfactory.ListFactory</title></head>
<body>
<h1>listfactory.ListFactory</h1><ul>
<li>
커뮤니티
<ul>
<li><a href="http://www.todayhumor.co.kr">오늘의 유머</a></li>
<li><a href="http://ruliweb.com/">루리웹</a></li>
</ul>
</li><li>
검색 엔진
<ul>
<li><a href="http://www.google.com">Google</a></li>
<li><a href="http://www.daum.net">Daum</a></li>
<li>
Naver
<ul>
<li><a href="http://www.naver.com">Naver</a></li>
<li><a href="http://m.naver.com">Naver Mobile</a></li>
</ul>
</li></ul>
</li></ul>
<hr><footer>By ledyx</footer></body>
</html>

Concrete Factory2 - DivFactory

<html>
<head><title>divfactory.DivFactory</title></head>
<body>
<h1>divfactory.DivFactory</h1>
<div>
<div style="border: 1px solid black; ; margin: 5px; padding: 5px">
<div>커뮤니티</div>

<div>
<span><a href="http://www.todayhumor.co.kr">오늘의 유머</a></span>

<span><a href="http://ruliweb.com/">루리웹</a></span>
</div>
</div>
<br>

<div style="border: 1px solid black; ; margin: 5px; padding: 5px">
<div>검색 엔진</div>

<div>
<span><a href="http://www.google.com">Google</a></span>

<span><a href="http://www.daum.net">Daum</a></span>

<div style="border: 1px solid black; ; margin: 5px; padding: 5px">
<div>Naver</div>

<div>
<span><a href="http://www.naver.com">Naver</a></span>

<span><a href="http://m.naver.com">Naver Mobile</a></span>
</div>
</div>
<br>
</div>
</div>
<br>
</div>
<hr><footer>By ledyx</footer></body>
</html>

Table of Contents

Abstract Factory Pattern

Factory

Abstract Factory

Abstract Products

Concrete Factories

Concrete Factory1 - ListFactory

Concrete Factory

Concrete Products

Concrete Factory2 - DivFactory

Concrete Factory

Concrete Products

Client

실행 결과

Concrete Factory1 - ListFactory

Concrete Factory2 - DivFactory