하위 클래스에서 구체적으로 처리.

• 상위 클래스에서 처리의 뼈대를 세우고, 구체적인 처리를 하위 클래스에서 실행.

GUI 앱에서 Menu, Sidebar를 열기/닫기/크기 얻기 동작을 한다고 가정.

/**
 * Template 역할
 */
public abstract class AbstractLayout {
	private int width;
	private int height;
	
	public AbstractLayout(int width, int height) {
		this.width = width;
		this.height = height;
	}
	
	public abstract void open();
	public abstract void close();
	
	public final int[] getMesasure() {
		return new int[] {width, height};
	}
}

public class MenuLayout extends AbstractLayout {

	public MenuLayout(int width, int height) {
		super(width, height);
	}

	@Override
	public void open() {
		System.out.println("Menu opened!");
	}

	@Override
	public void close() {
		System.out.println("Menu closed!");
	}
}

public class SidebarLayout extends AbstractLayout {

	public SidebarLayout(int width, int height) {
		super(width, height);
	}

	@Override
	public void open() {
		System.out.println("Sidebar opened!");
	}

	@Override
	public void close() {
		System.out.println("Sidebar closed!");
	}
}

public class Main {
	public static void main(String[] args) {
		AbstractLayout menuLayout = new MenuLayout(100, 100);
		AbstractLayout sidebarLayout = new SidebarLayout(100, 500);
		
		print(menuLayout);
		print(sidebarLayout);
	}
	
	private static void print(AbstractLayout layout) {
		layout.open();
		layout.close();
		
		for(int value : layout.getMesasure()) {
			System.out.println(value);
		}
		
		System.out.println();
	}
}

/*
Menu opened!
Menu closed!
100
100

Sidebar opened!
Sidebar closed!
100
500
*/