bintree.java

关于用java实现的程序

	    tmp2X += (tmp3X - src2)/5;
	    redraw();
	}
	tmp1Str = new String(); tmp2Str = new String();
	tmp3Str = new String(""+total);
	redraw();
    } // highlightLeftRightSubtree()

    public void tree2Matrices(int left, int right) {
	if (drawingPanel.getNoAnim())
	    return;
	int dest1X = drawingPanel.getOffset() + (left+1)*(horizSpace+2);
	int dest1Y = drawingPanel.getOffset() + 10 + (right+1)*(vertSpace+2);
	int dest2X = drawingPanel.getOffset() + 380 + (left+1)*(horizSpace+2);
	int dest2Y = drawingPanel.getOffset() + 10 + (right+1)*(vertSpace+2);

	tmp3X -= 10; redraw();
	tmp3X -= 10; redraw();
	tmp3X -= 10; redraw();
	tmp3X -= 10; redraw();

	tmp1Str = new String(((Node)nodeList.firstElement()).getLabel());
	tmp1X = tmp3X; tmp1Y = tmp3Y;
	tmp1X += 10; redraw();
	tmp1X += 10; redraw();
	tmp1X += 10; redraw();
	tmp1X += 10; redraw();

	int src1X = tmp3X; int src1Y = tmp3Y;
	int src2X = tmp1X; int src2Y = tmp1Y;
	for (int i = 0; i < 10; i++) {
	    tmp3X += (dest1X - src1X)/10;
	    tmp3Y += (dest1Y - src1Y)/10;
	    tmp1X += (dest2X - src2X)/10;
	    tmp1Y += (dest2Y - src2Y)/10;
	    redraw();
	}
	tmp3X = dest1X; tmp3Y = dest1Y;
	tmp1X = dest2X; tmp1Y = dest2Y; redraw();
	tmp3Str = new String();
	tmp1Str = new String();
    }

    /* ------------------------ Utils -------------------- */

    /**
     * Performs the exponent of <code>num</code> to the power of 
     * <code>pow</code>.
     * @param num Base.
     * @param pow Exponent.
     */
    public int power(int num, int pow) {
	int result = 1;
	for (int i = 0; i < pow; i++)
	    result *= num;
	return result;
    }

    /**
     * @return The position of the parent of node i.
     * @param i The node, whose parent is of interest.
     */
    public int parent(int i) {
	return (i/2);
    }

    /**
     * Returns the left child of node i.
     */
    public int left(int i) {
        return (2*i);
    }

    /**
     * Returns the right child of node i.
     */
    public int right(int i) {
        return (2*i + 1);
    }
 
    /* ------------------------ Graphical Primitives ------------------ */

    /**
     * Draws all graphical objects within this class.
     * @param g Graphical context.
     */
    public void draw(Graphics g) {
	drawTree(g);
    }

    /**
     * Draws all graphical objects within this class.
     * @param g Graphical context.
     */
    public void drawTree(Graphics g) {
	if (tmp1Str.length() > 0)
	    drawBox(g, tmp1X, tmp1Y, tmp1Str, 
		Color.white, Color.black, fixFont);

	if (tmp2Str.length() > 0)
	    drawBox(g, tmp2X, tmp2Y, tmp2Str, 
		Color.white, Color.black, fixFont);

	if (tmp3Str.length() > 0)
	    drawBox(g, tmp3X, tmp3Y, tmp3Str,
		Color.white, Color.black, fixFont);

	for (int i = 0; i < nodeList.size(); i++) {
	    Node node = (Node)nodeList.elementAt(i);
	    drawNode(g, node);
	}

	if (movingNode.getWeight() > -1)
	    drawNode(g, movingNode);
    }

    public void drawBox(Graphics g, int x, int y, String str,
                                Color fg, Color bg, Font font) {
	String blank = new String();
	for (int i = 0; i < 4-str.length(); i++)
	    blank = blank.concat(" ");
        g.setColor(bg);
        g.fillRect(x, y, horizSpace, vertSpace);
        g.setColor(Color.black);
        g.drawRect(x, y, horizSpace, vertSpace);
        g.setColor(fg);
        g.setFont(font);
        g.drawString(blank + str, x + 2, y + vertSpace - 4);
    }

    /**
     * Draw an arrowed line segment using the array of points.
     * @param g Graphical context
     * @param points The vortices of the line segment. 
     * An arrow head will be drawn using the last point in the array at the tip.
     */
    public void drawArrow(Graphics g, Point[] points) {
	// remember: no drawPolyline in jdk1.0.*
	int[] axPoints = new int[3], ayPoints = new int[3];
	g.setColor( Color.magenta );
	if (points.length < 3) {
	  Point endArrow = points[1], startArrow = points[0];
	  if (endArrow.y == startArrow.y) {
	    g.drawLine(startArrow.x, startArrow.y, endArrow.x, endArrow.y);
	    axPoints[0] = endArrow.x; ayPoints[0] = endArrow.y;
	    int unit = (endArrow.x - startArrow.x)/
			Math.abs(endArrow.x - startArrow.x);
	    axPoints[1] = endArrow.x - unit*2;
	    ayPoints[1] = endArrow.y - 2;
	    axPoints[2] = endArrow.x - unit*2;
	    ayPoints[2] = endArrow.y + 2;
	    g.fillPolygon(axPoints, ayPoints, 3);
	  } else if (endArrow.x == startArrow.x) {
	    g.drawLine(startArrow.x, startArrow.y, endArrow.x, endArrow.y);
	    axPoints[0] = endArrow.x; ayPoints[0] = endArrow.y;
	    int unit = (endArrow.y - startArrow.y)/
			Math.abs(endArrow.y - startArrow.y);
	    axPoints[1] = endArrow.x - 1;
	    ayPoints[1] = endArrow.y - unit*2;
	    axPoints[2] = endArrow.x + 2;
	    ayPoints[2] = endArrow.y - unit*2;
	    g.fillPolygon(axPoints, ayPoints, 3);
	  }
	} else if (points.length == 3) {
	    // draw a line for the first and second points then use
	    // drawArrow to draw the remaining segment
	    g.drawLine(points[0].x, points[0].y, points[1].x, points[1].y);
	    Point[] line = new Point[2];
	    line[0] = points[1];
	    line[1] = points[2];
	    drawArrow(g, line);
	}
    }

    /**
     * @param node The root node of the tree
     * @return The width of the tree in the number of pixels.
     */
    public int treeWidth(Node node) {
        return (rightMostPosn(node) - leftMostPosn(node));
    }
 
    /**
     * @param node The root node of the tree
     * @return The left most position of the tree
     */
    public int leftMostPosn(Node node) {
        if (node.isLeaf())
            return node.getX();
        else
            return leftMostPosn(node.getLeftNode());
    }
 
    /**
     * @param node The root node of the tree
     * @return The right most position of the tree
     */
    public int rightMostPosn(Node node) {
        if (node.isLeaf())
            return (node.getX() + 20);
        else
            return rightMostPosn(node.getRightNode());
    }
 
    /**
     * @param node The root node of the tree
     * @return The height of the tree in the number of pixels.
     */
    public int treeHeight(Node node) {
        return (bottomMostPosn(node) - node.getY());
    }
 
    /**
     * @param node The root node of the tree
     * @return The bottom most position of the tree
     */
    public int bottomMostPosn(Node node) {
	if (node == null) return 0;
        if (node.isLeaf())
            return (node.getY() + 30);
        else {
            int rightBottom = bottomMostPosn(node.getRightNode());
            int leftBottom = bottomMostPosn(node.getLeftNode());
            return (rightBottom > leftBottom ? rightBottom : leftBottom);
        }
    }

    /**
     * Drawing a leaf node of the heap.
     * @param g Graphical context
     * @param node The node to be drawn
     */
    public void drawLeafNode(Graphics g, Node node) {
        int x = node.getX(); int y = node.getY();
        int weight = node.getWeight();
        if (node.highlight)
            g.setColor(Color.black);
        else
            g.setColor( Color.blue );
        g.fillRect(x, y, 20, 30);
	g.setColor(Color.black);
	g.drawRect(x, y, 20, 30);
	if (node.getLabel().length() > 0) {
	    g.setColor( Color.yellow );
	    g.setFont( hugeFont );
	    g.drawString(node.getLabel(), node.getX() + 5, node.getY() + 12);
	}
        g.setColor( Color.white );
	g.setFont( bigFont );
        g.drawString(""+node.getWeight(), node.getX() + 2, node.getY()+27);
    }

    /**
     * Draw a node of the array representation of the heap.
     * @param g Graphical context
     * @param x The x coordinate of the top left corner of the node
     * @param y The y coordinate of the top left corner of the node
     * @param node The node to be drawn
     */
    public void drawArrayNode(Graphics g, int x, int y, Node node) {
        int weight = node.getWeight();
        if (node.highlight)
            g.setColor(Color.black);
        else
            g.setColor( Color.red );
        g.fillRect(x, y, 20, 30);
	g.setColor(Color.black);
	g.drawRect(x, y, 20, 30);
        g.setFont(hugeFont);
        g.setColor( Color.yellow );
        g.drawString(""+weight, x+2, y+25);
    }

    /**
     * Drawing a node based on the input parameters.
     * @param g Graphical context
     * @param node The node to be drawn
     */
    public void drawNode(Graphics g, Node node) {
        if (node.highlight)
            g.setColor(Color.black);
        else
            g.setColor( darkgreen );
        g.fillRect(node.getX(), node.getY(), 20, 30);
	g.setColor(Color.black);
	g.drawRect(node.getX(), node.getY(), 20, 30);
	if (node.getLabel().length() > 0) {
	    g.setColor( Color.yellow );
	    g.setFont( hugeFont );
	    g.drawString(node.getLabel(), node.getX() + 5, node.getY() + 12);
	}
        g.setColor( Color.white );
	g.setFont( bigFont );
        g.drawString(""+node.getWeight(), node.getX() + 2, node.getY()+27);
 
        // draw links to children
	if (node.getLeftNode() != null) {
            g.setColor( Color.black );
            g.drawLine(node.getX() + 6, node.getY() + 30,
                node.getLeftNode().getX() + 10, node.getLeftNode().getY());
	    if (node.highlightLeft) {
                g.drawLine(node.getX() + 5, node.getY() + 30,
                    node.getLeftNode().getX() + 9, node.getLeftNode().getY());
                g.drawLine(node.getX() + 4, node.getY() + 30,
                    node.getLeftNode().getX() + 8, node.getLeftNode().getY());
	    }
	}

	if (node.getRightNode() != null) {
	    g.setColor( Color.black );
            g.drawLine(node.getX() + 14, node.getY() + 30,
                node.getRightNode().getX() + 10, node.getRightNode().getY());
	    if (node.highlightRight) {
                g.drawLine(node.getX() + 15, node.getY() + 30,
                    node.getRightNode().getX() + 11, node.getRightNode().getY());
                g.drawLine(node.getX() + 16, node.getY() + 30,
                    node.getRightNode().getX() + 12, node.getRightNode().getY());
	    }
	}
    }

    /**
     * Move the tree starting with node dx pixels to the right and dy
     * pixels down.
     * @param node The root node of the tree to be moved.
     * @param dx The change in x direction.
     * @param dy The change in y direction.
     */
    public void moveNode(Node node, int dx, int dy) {
	if (node == null) return;
	node.moveNode(dx, dy);
    }

    public void highlightNode(Node node) {
	node.highlight = true;
	if (node.getLeftNode() != null)
	    highlightNode(node.getLeftNode());
	if (node.getRightNode() != null)
	    highlightNode(node.getRightNode());
    }

    public void restoreNode(Node node) {
	node.highlight = false;
	if (node.getLeftNode() != null)
	    restoreNode(node.getLeftNode());
	if (node.getRightNode() != null)
	    restoreNode(node.getRightNode());
    }

    public Node getNodeAt(int posn) {
	Node posnNode = (Node)posnList.elementAt(posn-1);
	for (int i = 0; i < nodeList.size(); i++) {
	    Node node = (Node)nodeList.elementAt(i);
	    if (node.getX() == posnNode.getX() && node.getY() == posnNode.getY()) {
		return node;
	    }
	}
	return null;
    }

    public int sumNodeWeight(Node node) {
	if (node == null) return 0;
	return (sumNodeWeight(node.getRightNode()) + 
		sumNodeWeight(node.getLeftNode()) + 
		node.getWeight());
    }

    Node root = null;
    public void setRoot(Node node) {
	this.root = node;
    }

    public int getX() {
	return getNodeAt(1).getX();
    }

    public int getY() {
	return getNodeAt(1).getY();
    }

    public void move(int x, int y) {
	Point orig = new Point(0, 0);
	if (root != null) {
	    orig.x = root.getX();
	    orig.y = root.getY();
	    root.move(x, y);
	} else {
	    root = (Node)nodeList.firstElement();
	    if (root != null) {
		orig.x = root.getX();
		orig.y = root.getY();
		root.move(x, y);
	    }
	}

	if (root != null) {
	    int dx = x - orig.x;
	    int dy = y - orig.y;
	    if (tmp1Str.length() > 0) {
		tmp1X += dx;
		tmp1Y += dy;
	    }

	    if (tmp2Str.length() > 0) {
		tmp2X += dx;
		tmp2Y += dy;
	    }

	    if (tmp3Str.length() > 0) {
		tmp3X += dx;
		tmp3Y += dy;
	    }
	}
    }
}