排序或比较的方法 集合

 

比较Date类

 

java.utli.Date date1 = new java.util.Date(2013,1,1);

java.utli.Date date2 = new java.util.Date(2011,1,1);

System.out.printn(date1.compareTo(date2));

 

 

Arrays类排序数组:

string cities = { "abs","bao","daj","dae"};

java.util.Arrays.sort(cities);　　　　//用Arrays类直接排序

 

 

实现Comparable接口实现排序:

　　例:比较卡片类:

class Card  implements Comparable<Card>{        
    //表明Comparable类用于比较cara类

    Shape shape;

    public Shape getShape() {
        return shape;
    }

    public void setShape(Shape shape) {
        this.shape = shape;
    }

   
    @Override
    public int compareTo(Card card) {       
         //实现Comparable类中的方法,用于比较
        
        // TODO 自动生成的方法存根
        if(card.getShape().getArea() > this.shape.getArea()) 
            return 1;
        
        else if(card.getShape().getArea() == this.shape.getArea())
            return 0;
        
        else
            return -1;
    }
}