[자바] Template Method 패턴

package templateomethod;

public abstract class AbstractDisplay {
	public abstract void open();
	public abstract void print();
	public abstract void close();
	
	public final void display() {
		open();
		for (int i = 0; i < 5; i++) {
			print();
		}
		close();
	}
}

package templateomethod;

public class CharDisplay extends AbstractDisplay {

	private char ch;
	
	public CharDisplay(char ch) {
		this.ch = ch;
	}
	
	@Override
	public void open() {
		System.out.print("<<");
	}

	@Override
	public void print() {
		System.out.print(ch);
	}

	@Override
	public void close() {
		System.out.println(">>");
	}

}

package templateomethod;

public class StringDisplay extends AbstractDisplay {

	private String str;
	private int width;
	
	public StringDisplay(String str) {
		this.str = str;
		this.width = str.getBytes().length;
	}
	
	@Override
	public void open() {
		printLine();
	}

	@Override
	public void print() {
		System.out.println("|" + str + "|");
	}

	@Override
	public void close() {
		printLine();
	}

	private void printLine() {
		System.out.print("+");
		for (int i = 0; i < width; i++) {
			System.out.print("-");
		}
		System.out.println("+");
	}
}

package templateomethod;

public class Main {
	public static void main(String[] args) {
		AbstractDisplay d1 = new CharDisplay('H');
		d1.display();
		
		AbstractDisplay d2 = new StringDisplay("Hello, World");
		d2.display();
	}
}

 

결과:

<<HHHHH>>
+------------+
|Hello, World|
|Hello, World|
|Hello, World|
|Hello, World|
|Hello, World|
+------------+