用java 定义Point类描述屏幕上的一个点。该 类包括点的x和y两个坐标，及对点进行的相 关操作，如：取得点的坐标值，对点的坐标进 行赋值。此类属于MyPackageTwoD包。此包 中另一个Rectangle类可以实现矩形的基本操 作，包含Point. width height等了个变量 及构造方法和其他方法。文件 TestPackage.java中包含maino方法，定义如 T:

以下是Point类的定义：

package MyPackageTwoD;

public class Point {
    private int x;
    private int y;

    public Point(int x, int y) {
        this.x = x;
        this.y = y;
    }

    public int getX() {
        return x;
    }

    public int getY() {
        return y;
    }

    public void setX(int x) {
        this.x = x;
    }

    public void setY(int y) {
        this.y = y;
    }
}

以下是Rectangle类的定义：

package MyPackageTwoD;

public class Rectangle {
    private Point topLeft;
    private int width;
    private int height;

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

    public Point getTopLeft() {
        return topLeft;
    }

    public int getWidth() {
        return width;
    }

    public int getHeight() {
        return height;
    }

    public void setTopLeft(Point topLeft) {
        this.topLeft = topLeft;
    }

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

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

以下是TestPackage.java中的main方法：

package MyPackageTwoD;

public class TestPackage {
    public static void main(String[] args) {
        Point p = new Point(3, 4);
        System.out.println("x = " + p.getX() + ", y = " + p.getY());

        Rectangle r = new Rectangle(p, 5, 6);
        System.out.println("width = " + r.getWidth() + ", height = " + r.getHeight());
    }
}