design_model（11）flyweight

Posted 2021-01-03 gg128

1.享元模式//假如已经有了这么对象就是用这个对象，没有就创建这个对象，例如String等。

2.实例

public class Color {
    private  String  color;

	public String getColor() {
		return color;
	}

	public void setColor(String color) {
		this.color = color;
	}
    
}

public class FlyWeight {
	private Map<String, Color> colors = new HashMap<>();

	public Color getColor(String str) {
		if (colors.containsKey(str)) {
			return colors.get(str);
		} else {
			Color color = new Color();
			colors.put(str, color);
			return color;
		}
	}
}

public class Client {
	public static void main(String[] args) {
		FlyWeight flyWeight = new FlyWeight();
		Color color = flyWeight.getColor("红色");
		Color color2 = flyWeight.getColor("红色");
		System.out.println(color == color2);// true
	}
}