import java.awt.*;
import java.awt.geom.GeneralPath;
import javax.swing.*;

public class DrawCircle extends JPanel
{
Point[] points;
GeneralPath circle;
final int INC = 5;

public DrawCircle()
{
    initPoints();

    initCircle();
}

private void initPoints()
{
    int numberOfPoints = 360/INC;
    points = new Point[numberOfPoints];
    double cx = 200.0;
    double cy = 200.0;
    double r = 100.0;
    // Dimension variables
    int count = 0;
    for(int theta = 0; theta < 360; theta+=INC)
    {
        int x = (int)(cx + r * Math.cos(Math.toRadians(theta)));
        int y = (int)(cy + r * Math.sin(Math.toRadians(theta)));
        points[count++] = new Point(x, y);
    }
}

private void initCircle()
{
    circle = new GeneralPath();
    for(int j = 0; j < points.length; j++)
    {
        if(j == 0)
            circle.moveTo(points[j].x, points[j].y);
        else
            circle.lineTo(points[j].x, points[j].y);
    }
    circle.closePath();
}

protected void paintComponent(Graphics g)
{
    // fill and color
    super.paintComponent(g);
    Graphics2D g2 = (Graphics2D)g;
    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                        RenderingHints.VALUE_ANTIALIAS_ON);
    g2.setPaint(Color.red);
    g2.fill(circle);
    g2.setPaint(Color.red);
    Point p1 = points[0];
    for(int j = 1; j <= points.length; j++)
    {
        Point p2 = points[j % points.length];
        g2.drawLine(p1.x, p1.y, p2.x, p2.y);
        // Line coordinates
        p1 = p2;
    }
}

public static void main(String[] args)
{
    //Main functions
    JFrame f = new JFrame();
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.setContentPane(new DrawCircle());
    f.setSize(400,400);
    // Frame
    f.setLocation(200,200);
    // Center
    f.setVisible(true);
    }
}

public class StopWatch {
    private final long before;

    StopWatch() {
        before = System.currentTimeMillis();
        //before = System.nanoTime();
    }

    public long elapsedTime() {
        long after = System.currentTimeMillis();
        //long after = System.nanoTime();
        return after - before;
   }
}