Java设计模式之多例设计模式

多例设计模式是单例模式的拓展，单例模式是只保留一个类的实例化对象，而多例模式是定义了多个对象。是有限个数对象的。

public class ManyCases {

public static void main(String[] args) {
    Color color = Color.getInstance("blue");
    System.out.println(color.getTitle());

}

}

//多例设计模式
class Color{
private static final Color RED = new Color("red");
private static final Color BLUE = new Color("blue");
private static final Color GREEN= new Color("green");
private static final Color YELLOW = new Color("yellow");

private String title;
private Color(String title){
    this.title = title;
}

public static Color getInstance(String title){
    switch (title){
        case "red":
            return RED;
        case "blue":
            return BLUE;
        case "green":
            return GREEN;
        case "yellow":
            return YELLOW;
        default:
            return null;
    }
}

public String getTitle(){
    return title;
}

}