public abstract Dimension getPreferredSize(Container parent);
public abstract void layoutContainer(Container parent);

import com.sun.lwuit.Component;
import com.sun.lwuit.Container;
import com.sun.lwuit.geom.Dimension;
import com.sun.lwuit.layouts.Layout;
import com.sun.lwuit.plaf.Style;
 
/**
 * @author ifrach shai
 */
public class CircularLayout extends Layout {
 
	private int startAngel;
	private int clockWise;
 
	public CircularLayout()
	{
		this(270, true);
	}
 
	public CircularLayout(int startAngel, boolean clockWise)
	{
		this.startAngel = startAngel;
		this.clockWise = clockWise ? -1 : 1;
	}
 
	/**
	* returns the preffered size the layout needs in order to properly arrange the components
	*/
	public Dimension getPreferredSize(Container parent)
	{
		int components = parent.getComponentCount();
		double largestDiameter = 0;
		for (int iter = 0; iter < components; iter++)
		{
			Component current = parent.getComponentAt(iter);
			Dimension d = current.getPreferredSize();
			largestDiameter = Math.max(largestDiameter, Math.sqrt(d.getWidth() * d.getWidth() + d.getHeight()
					* d.getHeight()));
		}
		double angelPart = 360f / components;
		double otherAngel = (180 - angelPart) / 2;
		int radius = (int) (largestDiameter * Math.sin(Math.toRadians(otherAngel)) / Math
				.sin(Math.toRadians(angelPart)));
		return new Dimension((int) (radius * 2 + largestDiameter), (int) (radius * 2 + largestDiameter));
 
	}
 
	/**
	* this method arranges the components within the container by setting their relative x,y values as well as their width,height
	* even if the size allocated to this container is smaller than the one returned in the getPrefferedSize method this method will still arrange
	* the components in a nice circle but there will be some overlapping.
	*/
	public void layoutContainer(Container parent)
	{
		int components = parent.getComponentCount();
		double angelPart = 360f / components;
		Style parentStyle = parent.getStyle();
		int centerPosX = (parent.getLayoutWidth() - parentStyle.getMargin(Component.LEFT) - parentStyle
				.getMargin(Component.RIGHT))
				/ 2 + parentStyle.getMargin(Component.LEFT);
		int centerPosY = (parent.getLayoutHeight() - parentStyle.getMargin(Component.TOP) - parentStyle
				.getMargin(Component.BOTTOM))
				/ 2 + parentStyle.getMargin(Component.TOP);
		double largestDiameter = 0;
		for (int iter = 0; iter < components; iter++)
		{
			Component current = parent.getComponentAt(iter);
			Dimension d = current.getPreferredSize();
			largestDiameter = Math.max(largestDiameter, Math.sqrt(d.getWidth() * d.getWidth() + d.getHeight()
					* d.getHeight()));
		}
		int radius = (int) (Math.min(parent.getLayoutWidth() - largestDiameter, parent.getLayoutHeight()
				- largestDiameter) / 2);
		for (int iter = 0; iter < components; iter++)
		{
			Component current = parent.getComponentAt(iter);
			Dimension d = current.getPreferredSize();
			current.setSize(d);
			double radianAgnel = Math.toRadians(startAngel + clockWise * iter * angelPart);
			current.setX(centerPosX + (int) (radius * Math.cos(radianAgnel)) - current.getWidth() / 2);
			current.setY(centerPosY + (int) (radius * Math.sin(radianAgnel)) - current.getHeight() / 2);
		}
 
	}
 
}