public class RectangleComparator implements Comparator<Rectangle2D> {
double x1;
double x2;
double y1;
double y2;
double w1;
double w2;
double h1;
double h2;
@Override
public int compare(Rectangle2D o1, Rectangle2D o2) {
x1 = o1.getX();
x2 = o2.getX();
y1 = o1.getY();
y2 = o2.getY();
w1 = o1.getWidth();
w2 = o2.getWidth();
h1 = o1.getHeight();
h2 = o2.getHeight();
int result = -1;
if (x1 == x2)
result = 0;
if (result == 0)
{
if (y1 == y2)
result = 0;
}
if (result == 0)
{
if (w1 == w2)
result = 0;
}
if (result == 0)
{
if (h1 == h2)
result = 0;
}
return result;
}
public class RectangleTester {
public static void main(String[] args)
{
ArrayList <Rectangle2D> rect = new ArrayList<Rectangle2D>();
rect.add(new Rectangle2D.Double(20,15,14, 10));
rect.add(new Rectangle2D.Double(20,16,11, 5));
rect.add(new Rectangle2D.Double(17,28,90, 100));
rect.add(new Rectangle2D.Double(15,9,60, 75));
rect.add(new Rectangle2D.Double(41,56,21, 19));
Collections.sort(rect, new RectangleComparator());
for (Rectangle2D temp : rect)
System.out.println(temp.toString());
}
}
}
嗨,我试图通过编写一个小程序来对矩形列表进行排序来学习比较器。但是,当我运行它时,输出与原始列表相反,而不是排序列表。我不太了解比较器,如果你们能提供一些帮助我真的很感激,谢谢。
答案 0 :(得分:2)
你的同事很糟糕。它有点处理平等,但没有别的。 尝试更像:
result = x2-x1;
if (result == 0) {
result = y2-y1;
if (result == 0) {
result = w2-w1;
等等。
答案 1 :(得分:1)
我认为你应该使用其他一些计算,如&#34; area&#34;比较它将是更有意义的矩形比较: 类似的东西:
area1 = o1.getWidth() * o1.getHeight();
area2 = o2.getWidth() * o2.getHeight();
if (area1 == area2)
return 0;
else if (area > area2)
return -1;
else if (area1 < area2)
return 1;
所以这将对矩形区域
进行排序