gistfile1.txt

public abstract class Slide {
  private String title;
  private String text;

  public class Builder {
    Slide slide;
		
    public Builder(String type) {
      if ("ICON".equals(type)) {
        slide = new IconSlide();
      } else {
        slide = new AgeSlide();
      }
    }
		
    public Builder setTitle(String title) {
      slide.title = title;
      return this;
     }
		
    public Slide build() {
      return slide;
    }
  }
}

public class IconSlide extends Slide {
	Icon icon;
}

public class AgeSlide extends Slide {
	int age;
}