how to create a Graphics object?

I am trying to create a small animation applet which requires to generate a Graphics object dynamically. I am using getGraphics() method on a Canvas object and then painting on that but when I run my program it says NullPointerException.

I don't know why the method getGraphics() is not returning any Graphics object. A part of my code is below.

class Fan extends Thread
        private int r,x,y,deg;
        private Canvas myfan;
        public boolean direction;

        Fan(int new_r, int new_x, int new_y, int new_deg, Canvas C)
                this.direction = true;
        }// constructor

        public void draw()
                int rx, ry;
                Graphics g = myfan.getGraphics();
            if (myfan.getGraphics()==null)
                rx=(int) (r*Math.cos(deg));
                ry=(int) (r*Math.sin(deg));

I appreciate your help.

Thank you,
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You never created the Canvas you are trying to
do a getGraphics() on.  Canvas myfan = new Canvas();

should fix your NullPointer problem.


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kunalaAuthor Commented:
Thank you
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