HelloWorld com Design Patterns

interface Printer {
   void print(Message message);
}

class Message {
   
   private String message;

   public Message(String message) {
      this.message = message;
   }

   public void print(Printer printer) {
      printer.print(this);
   }

   public String toString() {
      return message;
   }
}

abstract class AbstractPrinterFactory {
   
   public static AbstractPrinterFactory getFactory() {
      return new SystemOutPrinterFactory();
   }

   public abstract Printer getPrinter();
}

class SystemOutPrinterFactory extends AbstractPrinterFactory {

   public Printer getPrinter() {
      return new SystemOutPrinter();
   }

}

class SystemOutPrinter implements Printer {
   
   public void print(Message message) {

      System.out.println(message);

   }

}

public class HelloWorld {

   public static void main(String[] args) {
      Message message = new Message("Hello, World!");
      AbstractPrinterFactory factory = AbstractPrinterFactory.getFactory();
      Printer printer = factory.getPrinter();
      message.print(printer);
   }

}