用Java在鼠标方向上发送圆圈

Question

我正在做一个游戏，当我单击鼠标时，球会射击。我不太熟悉Java，所以很困惑。就像，球从屏幕的底部中间开始（因此，ballx和bally都有其位置），一旦鼠标单击一个方向，球便会朝该方向射击... 谢谢

package graphics;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;

public class Ballz extends LASSPanel
{
//Variables for the circle (Global Variables)

int circleX, circleY, circleDX, circleDY, circleSize, circleSpeed;

//Colors
Color circleColor;
Color backgroundColor;
Dimension size;
double mouseX;
double mouseY;

public Ballz()
{
    //Ball Variables
    circleX = 250;
    circleY = 250;
    circleSize = 15;
    circleSpeed = (1);  

    circleColor = new Color (245,245,245);
    backgroundColor = new Color (28,28,28);
    size = new Dimension(0,0);
}
public void update()
{
    //Get size of screen
    getSize(size);

    //Get mouse coordinates
    mouseX = getMouseX();
    mouseY = getMouseY();

    //Call custom method to find angle

    //Screen borders
    if (circleX >= (size.width) - circleSize)
    {
        circleDX = -circleDX;
        circleX = size.width-circleSize;

    }
    if (circleX <= 0)
    {
        circleDX = -circleDX;
        circleX = 0;
    }
    if (circleY >= (size.height -circleSize))
    {
        circleDY = -circleDY;
        circleY = size.height-circleSize;   
    }
    if (circleY <= 0)
    {
        circleDY = -circleDY;
        circleY = 0;
    }

    circleX += circleDX;
    circleY += circleDY;

    repaint();

}

public void paint(Graphics g)
{


    //Game Colors
    g.setColor(circleColor);
    g.fillOval(circleX, circleY, circleSize, circleSize);
    setBackground(backgroundColor); 

}
//This is the code that will get the direction between two points that I give.
    public double getAngle (int x1, int x2, int y1, int y2)
{

    double Direction = 0;

    double dx = y2-y1;
    double dy = x2-x1;

     Direction = Math.atan2(dy,dx);

    return Direction;

}
}