Strange extra shape drawn

[eyebrow]

The program below has a strange (to me) error.
The program is supposed to ask the user for a circle's radius and then for a number of degrees.
It will then draw the circle with a filled red arc using the degrees entered (along with some stat calculations that are shown as strings).
The strange thing is that if you enter a radius larger than 35 or so and a number of degrees greater than 270, an extra bit of filled arc shows up at the top-left of the frame. It appears that a second, unasked for filled arc is being drawn at the frame's 'origin'.
Thanks,
eyebrow.

import java.awt.Color;
import javax.swing.JFrame;
import java.awt.Graphics;
import javax.swing.JOptionPane;

public class P02 extends JFrame {

// Declare global constants
private static final int FRAME_SIZE = 400;
// Declare class level variables
int halfFrameSize;
int radiusOfCircle;
int degreeOfAngle;
int fillArcX;
int fillArcY;
double radianOfAngle;
double arcLength;
double areaOfSlice;
int diameterOfCircle;

@Override
public void paint(Graphics canvas) {

// Math for canvas output.
fillArcX = halfFrameSize - radiusOfCircle;
fillArcY = halfFrameSize - radiusOfCircle;
halfFrameSize = FRAME_SIZE / 2;
diameterOfCircle = radiusOfCircle * 2;
radianOfAngle = (degreeOfAngle * (Math.PI / 180));
arcLength = radianOfAngle * radiusOfCircle;
areaOfSlice = Math.pow(radiusOfCircle,2) * 0.5 * radianOfAngle;

// Draws circle with radius input from user.
canvas.drawOval(halfFrameSize-radiusOfCircle,
halfFrameSize-radiusOfCircle,
diameterOfCircle, diameterOfCircle);

// Draws X and Y axes
canvas.drawLine(halfFrameSize, 0, halfFrameSize, FRAME_SIZE);
canvas.drawLine(0, halfFrameSize, FRAME_SIZE, halfFrameSize);

// Draws output strings
canvas.drawString(("Stats:"),5,50);
canvas.drawString(("Radius: " + radiusOfCircle),5,65);
canvas.drawString(("Angle Degrees: " + degreeOfAngle),5,80);
canvas.drawString("Angle Radians: " + String.format("%1.3f",
radianOfAngle),5,95);
canvas.drawString("Arc Length: " + String.format("%1.3f",
arcLength),5,110);
canvas.drawString("Slice Area: " + String.format("%1.3f",
areaOfSlice),5,125);

// Fills in arc on inside of circle using radius and degree input from
// user.
canvas.setColor(Color.RED);
canvas.fillArc(fillArcX,fillArcY,radiusOfCircle * 2,radiusOfCircle * 2,
0,degreeOfAngle);
}// end paint

// The P02 method sets up the frame (window) size and makes sure the frame
// is erased properly when the program is closed.
public P02() {
setSize(FRAME_SIZE, FRAME_SIZE);
setDefaultCloseOperation(EXIT_ON_CLOSE);
// JOptionPanes asking for user input.
String radiusString = JOptionPane.showInputDialog(
"Enter the radius of the circle (10..150)");
radiusOfCircle = Integer.parseInt(radiusString);
String angleString = JOptionPane.showInputDialog(
"Enter the angle in degrees (0..360)");
degreeOfAngle = Integer.parseInt(angleString);
}// end P02

// Creates the frame and makes it visible.
public static void main(String[] args) {
P02 guiWindow = new P02();
guiWindow.setVisible(true);
}// end main
}// end Jframe

[Fubarable]

I don't get your problem but get other issues with your code. I recommend:

• Draw in the paintComponent method of a class that extends JPanel, and then either place that JPanel in the JFrame's contentPane or set it as the JFrame's contentPane.
• You usually want to call the class's super's paint or paintComponent method (depending on if it's a paint or paintComponent override method) as the first method call in the overridden method.
• Be sure to call your Swing code on the event thread. This can be done by putting the two lines of code in your main method inside of a Runnable's run method and adding the Runnable to the event queue using SwingUtilities.invokeLater(...) method.

[eyebrow]

Ok. Thanks for the feedback.
When I called the super's paint, the problem went away. It looks like I'll have to read up on what exactly is going on, but your observation really helped.
Thanks again,
eyebrow.