java - 使用Iterator调用多参数方法

我正在尝试按区域对形状列表进行排序。我正在使用Iterator在列表中移动并在列表的每个元素上调用Rectangle.calculateArea，但是打印的列表不会输出每个元素的面积。输出是对每个元素的十六进制引用。下面是输出，后跟代码。如何使我的输出显示计算面积？

矩形区域：
矩形@ 15db9742
矩形@ 6d06d69c
矩形@ 7852e922
矩形@ 4e25154f
矩形@ 70dea4e

public class RectangleSortTest {
public static void main (String[] args) {
List<Rectangle> list = new ArrayList<>();
//Create Rectangle ArrayList

list.add(new Rectangle(4, 3));
list.add(new Rectangle(3, 3));
list.add(new Rectangle(4, 4));
list.add(new Rectangle(5, 1));
list.add(new Rectangle(1, 1));
//Add Rectangle elements to Rectangle list



calculateListArea(list);
//Calculates area for each rectangle element

System.out.print("Rectangle Areas:");
printList(list);
//Print rectangle list after area calculation


}

private static void calculateListArea(List<Rectangle> list) {//Calculates Rectangle list areas
    ListIterator<Rectangle> iterator = list.listIterator();

    while (iterator.hasNext()) {
        Rectangle rectangleElement = iterator.next();
        Rectangle.calculateArea(rectangleElement.getWidth(), rectangleElement.getHeight());
    }
}

private static void printList(List<Rectangle> list) {//Print Rectangle list
    for (Rectangle element: list) {
        System.out.printf("%n%s", element);
    }
}

}

最佳答案

您可以使其简单，如下所示：

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class RectangleSortTest {
    public static void main(String[] args) {

        List<Rectangle> list = new ArrayList<Rectangle>();

        // Add some rectangle to a list
        list.add(new Rectangle(4, 3));
        list.add(new Rectangle(3, 3));
        list.add(new Rectangle(4, 4));
        list.add(new Rectangle(5, 1));
        list.add(new Rectangle(1, 1));

        // Sort the list on area
        Collections.sort(list);

        // Print the list
        System.out.println("Rectangles in ascending order of areas:");
        printList(list);
    }

    static void printList(List<Rectangle> list) {
        for (Rectangle element : list) {
            System.out.println(element);
        }
    }
}

class Rectangle implements Comparable<Rectangle> {
    int width, height, area;

    public Rectangle(int width, int height) {
        this.width = width;
        this.height = height;
    }

    public int getWidth() {
        return width;
    }

    public void setWidth(int width) {
        this.width = width;
    }

    public int getHeight() {
        return height;
    }

    public void setHeight(int height) {
        this.height = height;
    }

    public int getArea() {
        return width * height;
    }

    @Override
    public int compareTo(Rectangle rectangle) {
        if (this.getArea() > rectangle.getArea())
            return 1;
        else if (this.getArea() == rectangle.getArea())
            return 0;
        else
            return -1;
    }

    @Override
    public String toString() {
        return "Rectangle [width=" + width + ", height=" + height + ", area=" + this.getArea() + "]";
    }
}

输出：

Rectangles in ascending order of areas:
Rectangle [width=1, height=1, area=1]
Rectangle [width=5, height=1, area=5]
Rectangle [width=3, height=3, area=9]
Rectangle [width=4, height=3, area=12]
Rectangle [width=4, height=4, area=16]

关于java - 使用Iterator调用多参数方法，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/58905051/