Added abstract classes for quad tree

src/main/java/at/jotschi/quadtree/AbstractNode.java

@@ -0,0 +1,83 @@
+package at.jotschi.quadtree;
+
+import java.awt.Dimension;
+import java.awt.Point;
+
+public abstract class AbstractNode {
+
+	/**
+	 * Default value for amount of elements
+	 */
+	protected final int MAX_ELEMENTS = 4;
+
+	/**
+	 * Default value for max depth
+	 */
+	protected final int MAX_DEPTH = 4;
+
+	public static enum Cell {
+		TOP_LEFT, BOTTOM_RIGHT, BOTTOM_LEFT, TOP_RIGHT
+	}
+
+	protected Dimension bounds;
+	protected Point startCoordinates;
+	protected int maxDepth;
+	protected int maxElements;
+	protected int depth;
+
+	public AbstractNode(Point startCoordinates, Dimension bounds, int depth) {
+		this.startCoordinates = startCoordinates;
+		this.bounds = bounds;
+		this.depth = depth;
+		this.maxDepth = MAX_DEPTH;
+		this.maxElements = MAX_ELEMENTS;
+	}
+
+	public AbstractNode(Point startCoordinates, Dimension bounds, int depth,
+			int maxDepth, int maxChildren) {
+		this.startCoordinates = startCoordinates;
+		this.bounds = bounds;
+		this.maxDepth = maxDepth;
+		this.maxElements = maxChildren;
+		this.depth = depth;
+	}
+
+	/**
+	 * Returns the bounds for this Node
+	 * 
+	 * @return
+	 */
+	public Dimension getBounds() {
+		return this.bounds;
+	}
+
+	/**
+	 * Returns the startCoordinates for this Node
+	 * 
+	 * @return
+	 */
+	public Point getStartCoordinates() {
+		return this.startCoordinates;
+	}
+
+	/**
+	 * Returns the max elements
+	 * 
+	 * @return
+	 */
+	public int getMaxElements() {
+		return this.maxElements;
+	}
+
+	/**
+	 * Returns the max depth
+	 * 
+	 * @return
+	 */
+	public int getMaxDepth() {
+		return this.maxDepth;
+	}
+
+	public abstract void subdivide(); 
+
+}

src/main/java/at/jotschi/quadtree/NodeElement.java → src/main/java/at/jotschi/quadtree/AbstractNodeElement.java

@@ -9,7 +9,7 @@
  * 
  */
 @SuppressWarnings("serial")
-public class NodeElement<T> extends Point {
+public abstract class AbstractNodeElement<T> extends Point {
 
 	private T element;
 
@@ -20,10 +20,13 @@ public class NodeElement<T> extends Point {
 	 * @param y
 	 * @param element
 	 */
-	public NodeElement(Point coordinates, T element) {
+	public AbstractNodeElement(Point coordinates, T element) {
 		super(coordinates);
 		this.element = element;
+	}
 
+	public AbstractNodeElement(T element) {
+		this.element = element;
 	}
 
 	/**

src/main/java/at/jotschi/quadtree/AbstractQuadTree.java

@@ -0,0 +1,49 @@
+package at.jotschi.quadtree;
+
+import java.awt.Dimension;
+import java.awt.Point;
+
+import at.jotschi.quadtree.impl.PointNode;
+
+public abstract class AbstractQuadTree<T> {
+
+	protected Dimension size;
+	protected Point startCoordinates;
+
+	public AbstractQuadTree(Point startCoordinates, Dimension size) {
+		this.size = size;
+		this.startCoordinates = startCoordinates;
+	}
+
+	/**
+	 * Returns the size
+	 * 
+	 * @return
+	 */
+	public Dimension getSize() {
+		return this.size;
+	}
+
+	/**
+	 * Returns the startCoordinates
+	 * 
+	 * @return
+	 */
+	public Point getStartCoordinates() {
+		return this.startCoordinates;
+	}
+
+	/**
+	 * Clear the QuadTree
+	 */
+	public abstract void clear();
+
+
+	/**
+	 * Return the root node of this quad tree
+	 * @return
+	 */
+	public abstract PointNode<T> getRootNode();
+
+
+}