Paint example

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.Point;
import java.awt.Shape;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Line2D;
import java.awt.geom.Rectangle2D;
import java.awt.print.PageFormat;
import java.awt.print.Printable;
import java.awt.print.PrinterException;
import java.awt.print.PrinterJob;
import java.util.ArrayList;
import java.util.Vector;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.RepaintManager;

public class Paint extends JFrame {
    //List of shapes
    private Vector<Shape> shapes;

    private int type;
    //Shapes color, with black as default
    private Color color = Color.black;
    private ArrayList<Color> colorList = new ArrayList<Color>();

    public Board board;
    public ShapeSelect ss;
    public ColorSelect colorSelect;

    //Shape select class' variables
    private String[] labels = { "Line", "Sircle", "Square", "Clear", "Print" };
    private JButton[] btns = new JButton[labels.length];


    //Variables used in the color selection
    private Color[] colors = { Color.black, Color.white, Color.gray, Color.blue,
            Color.lightGray, Color.green, Color.pink, Color.red,
            Color.magenta, Color.orange, Color.cyan, Color.yellow};
    private JButton[] btnColor = new JButton[colors.length];

    public Paint() {
        super("Paint");

        type = 0;

        board = new Board();
        add(board, BorderLayout.CENTER);

        ss = new ShapeSelect();
        add(ss, BorderLayout.SOUTH);

        colorSelect = new ColorSelect();
        add(colorSelect, BorderLayout.WEST);

        setSize(700,700);
        setVisible(true);
        setResizable(false);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setAlwaysOnTop(true);
    }

    private class Board extends JPanel implements MouseListener, MouseMotionListener,
                                                        Printable {

        //Mouse points
        private Point startPoint, endPoint;

        //Sets the number value of shapes
        private final int CIRCLE = 1;
        private final int LINE = 2;
        private final int RECTANGLE = 3;

        //shape coordinates
        int upperLeftX;
        int upperLeftY;
        int width;
        int height;

        public Board() {
            //Setup of the frame
            setBackground(Color.white);

            shapes = new Vector<Shape>();

            //sets the mouse points to null
            startPoint = null;
            endPoint = null;
            addMouseListener(this);
            addMouseMotionListener(this);

        }

        public void paintComponent(Graphics g) {
            super.paintComponent(g);

            Graphics2D g2 = (Graphics2D) g;
            for (int i = 0; i < shapes.size(); i++) {
                Shape s = (Shape) shapes.get(i);
                if (s != null)
                    g2.setColor(colorList.get(i));
                    g2.fill(s);
                    g2.draw(s);
            }
        }

        public void mousePressed(MouseEvent e) {
            startPoint = e.getPoint();

        }

        public void mouseReleased(MouseEvent e) {
            endPoint = e.getPoint();

            //creates an empty shape object to fill with spesified shape.
            Shape s = null;
            switch(type) {
            case (CIRCLE):
                //s = new Ellipse2D.float(height, width, upperLeftX, upperLeftY);
                //Up left
                if(endPoint.x < startPoint.x && endPoint.y < startPoint.y) {
                    height = startPoint.y - endPoint.y;
                    width = startPoint.x - endPoint.x;
                    upperLeftX = endPoint.x;
                    upperLeftY = endPoint.y;
                }
                //Up right
                if(endPoint.x > startPoint.x && endPoint.y < startPoint.y) {
                    height = startPoint.y - endPoint.y;
                    width = endPoint.x - startPoint.x;
                    upperLeftX = endPoint.x - width;
                    upperLeftY = startPoint.y - height;
                }
                //Down left
                if(endPoint.x < startPoint.x && endPoint.y > startPoint.y){
                    height = endPoint.y - startPoint.y;
                    width = startPoint.x - endPoint.x;
                    upperLeftX = startPoint.x - width;
                    upperLeftY = endPoint.y - height;

                }
                //Down right
                if(endPoint.x > startPoint.x && endPoint.y > startPoint.y){
                    height = endPoint.y - startPoint.y;
                    width = endPoint.x - startPoint.x;
                    upperLeftX = startPoint.x;
                    upperLeftY = startPoint.y;
                }

                s = new Ellipse2D.Double(upperLeftX, upperLeftY, width, height);
                break;
            case LINE:
                s = new Line2D.Double(startPoint.x, startPoint.y, endPoint.x, endPoint.y);
                break;
            case (RECTANGLE):
                //s = new Ellipse2D.float(height, width, upperLeftX, upperLeftY);
                //Up left
                if(endPoint.x < startPoint.x && endPoint.y < startPoint.y) {
                    height = startPoint.y - endPoint.y;
                    width = startPoint.x - endPoint.x;
                    upperLeftX = endPoint.x;
                    upperLeftY = endPoint.y;
                }
                //Up right
                if(endPoint.x > startPoint.x && endPoint.y < startPoint.y) {
                    height = startPoint.y - endPoint.y;
                    width = endPoint.x - startPoint.x;
                    upperLeftX = endPoint.x - width;
                    upperLeftY = startPoint.y - height;
                }
                //Down left
                if(endPoint.x < startPoint.x && endPoint.y > startPoint.y){
                    height = endPoint.y - startPoint.y;
                    width = startPoint.x - endPoint.x;
                    upperLeftX = startPoint.x - width;
                    upperLeftY = endPoint.y - height;

                }
                //Down right
                if(endPoint.x > startPoint.x && endPoint.y > startPoint.y){
                    height = endPoint.y - startPoint.y;
                    width = endPoint.x - startPoint.x;
                    upperLeftX = startPoint.x;
                    upperLeftY = startPoint.y;
                }

                s = new Rectangle2D.Double(upperLeftX, upperLeftY, width, height);
                break;
            }
            shapes.add(s);
            startPoint = null;
            endPoint = null;
            colorList.add(color);
            repaint();
        }

        public void mouseDragged(MouseEvent e) {
            //Creates the shapes when mouse is draged
            Graphics2D g = (Graphics2D) getGraphics();
            g.setXORMode(Color.white);

            switch (type) {
            case CIRCLE :
                //While you drag
                if(endPoint != null) {
                    //g.drawOval(upperLeft, BottomRight, width, height);
                    //Top
                    if(endPoint.y < startPoint.y){
                        upperLeftY = endPoint.y;
                        height = startPoint.y - endPoint.y;
                        width = endPoint.x - startPoint.x;
                        g.drawOval(startPoint.x, upperLeftY, width, height);
                    }
                    if(endPoint.y < startPoint.y && endPoint.x < startPoint.x) {
                        width = startPoint.x - endPoint.x;
                        height = startPoint.y - endPoint.y;
                        upperLeftX = startPoint.x - width;
                        upperLeftY = startPoint.y - height;
                        g.drawOval(upperLeftX, upperLeftY, width, height);
                    }
                    //Bottom
                    if(endPoint.x < startPoint.x) {
                        upperLeftX = endPoint.x;
                        width = startPoint.x - endPoint.x;
                        g.drawOval(upperLeftX, startPoint.y, width, endPoint.y - startPoint.y);
                    }
                    if(endPoint.x > startPoint.x && endPoint.y > startPoint.y) {
                        g.drawOval(startPoint.x, startPoint.y, endPoint.x
                                - startPoint.x, endPoint.y - startPoint.y);
                    }
                }

                //First time you drag
                endPoint = e.getPoint();
                //g.drawOval(upperLeft, BottomRight, width, height);
                //Top
                if(endPoint.y < startPoint.y){
                    upperLeftY = endPoint.y;
                    height = startPoint.y - endPoint.y;
                    width = endPoint.x - startPoint.x;
                    g.drawOval(startPoint.x, upperLeftY, width, height);
                }
                if(endPoint.y < startPoint.y && endPoint.x < startPoint.x) {
                    width = startPoint.x - endPoint.x;
                    height = startPoint.y - endPoint.y;
                    upperLeftX = startPoint.x - width;
                    upperLeftY = startPoint.y - height;
                    g.drawOval(upperLeftX, upperLeftY, width, height);
                }
                //Bottom
                if(endPoint.x < startPoint.x) {
                    upperLeftX = endPoint.x;
                    width = startPoint.x - endPoint.x;
                    g.drawOval(upperLeftX, startPoint.y, width, endPoint.y - startPoint.y);
                }
                if(endPoint.x > startPoint.x && endPoint.y > startPoint.y) {
                    g.drawOval(startPoint.x, startPoint.y, endPoint.x
                            - startPoint.x, endPoint.y - startPoint.y);
                }

                break;
            case LINE :
                //While you drag
                if(endPoint != null) {
                    g.drawLine(startPoint.x, startPoint.y, endPoint.x, endPoint.y);
                }

                //First time you drag
                endPoint = e.getPoint();
                g.drawLine(startPoint.x, startPoint.y, endPoint.x, endPoint.y);
                break;
            case RECTANGLE:
                //While you drag
                /*
                    x - the x coordinate of the rectangle to be drawn.
                    y - the y coordinate of the rectangle to be drawn.
                    width - the width of the rectangle to be drawn.
                    height - the height of the rectangle to be drawn.

                 */
                if(endPoint != null) {
                    //g.drawOval(upperLeft, BottomRight, width, height);
                    //Top
                    if(endPoint.y < startPoint.y){
                        upperLeftY = endPoint.y;
                        height = startPoint.y - endPoint.y;
                        width = endPoint.x - startPoint.x;
                        g.drawRect(startPoint.x, upperLeftY, width, height);
                    }
                    if(endPoint.y < startPoint.y && endPoint.x < startPoint.x) {
                        width = startPoint.x - endPoint.x;
                        height = startPoint.y - endPoint.y;
                        upperLeftX = startPoint.x - width;
                        upperLeftY = startPoint.y - height;
                        g.drawRect(upperLeftX, upperLeftY, width, height);
                    }
                    //Bottom
                    if(endPoint.x < startPoint.x) {
                        upperLeftX = endPoint.x;
                        width = startPoint.x - endPoint.x;
                        g.drawRect(upperLeftX, startPoint.y, width, endPoint.y - startPoint.y);
                    }
                    if(endPoint.x > startPoint.x && endPoint.y > startPoint.y) {
                        g.drawRect(startPoint.x, startPoint.y, endPoint.x
                                - startPoint.x, endPoint.y - startPoint.y);
                    }
                }
                //First time you drag
                endPoint = e.getPoint();
                if(endPoint.y < startPoint.y){
                    upperLeftY = endPoint.y;
                    height = startPoint.y - endPoint.y;
                    width = endPoint.x - startPoint.x;
                    g.drawRect(startPoint.x, upperLeftY, width, height);
                }
                if(endPoint.y < startPoint.y && endPoint.x < startPoint.x) {
                    width = startPoint.x - endPoint.x;
                    height = startPoint.y - endPoint.y;
                    upperLeftX = startPoint.x - width;
                    upperLeftY = startPoint.y - height;
                    g.drawRect(upperLeftX, upperLeftY, width, height);
                }
                //Bottom
                if(endPoint.x < startPoint.x) {
                    upperLeftX = endPoint.x;
                    width = startPoint.x - endPoint.x;
                    g.drawRect(upperLeftX, startPoint.y, width, endPoint.y - startPoint.y);
                }
                if(endPoint.x > startPoint.x && endPoint.y > startPoint.y) {
                    g.drawRect(startPoint.x, startPoint.y, endPoint.x
                            - startPoint.x, endPoint.y - startPoint.y);
                }
            }
        }

        public void mouseMoved(MouseEvent e) {
        }

        public void mouseClicked(MouseEvent e) {
        }

        public void mouseEntered(MouseEvent e) {
        }

        public void mouseExited(MouseEvent e) {
        }

        @Override
        public int print(Graphics g, PageFormat pageFormat, int pageIndex)
                throws PrinterException {
            if (pageIndex > 0) {
                return NO_SUCH_PAGE;
            } else {

                int x = (int) pageFormat.getImageableX() + 1;
                int y = (int) pageFormat.getImageableY() + 1;
                g.translate(x, y);
                RepaintManager rm = RepaintManager.currentManager(this);
                rm.setDoubleBufferingEnabled(false);
                paint(g);
                rm.setDoubleBufferingEnabled(true);
                return PAGE_EXISTS;
            }
        }


    }

    private class ShapeSelect extends JPanel {

        public ShapeSelect() {
            setLayout(new GridLayout(1,6));
            JButton btn;
            EventScanner scanner = new EventScanner();

            for (int i = 0; i < labels.length; i++) {
                btn = new JButton(labels[i]);
                btn.addActionListener(scanner);
                btns[i] = btn;
                add(btn);
            }
        }
    }

    private class ColorSelect extends JPanel implements ActionListener {

        public ColorSelect() {
            setLayout(new GridLayout(colors.length / 2, 2));

            JButton btn;
            for (int i = 0; i < colors.length; i++) {
                btn = new JButton();
                if(i == 0) {
                    btn.setText("X");
                }
                btn.setBackground(colors[i]);
                btn.addActionListener(this);
                btnColor[i] = btn;
                add(btn);
            }
        }

        public void actionPerformed(ActionEvent e) {
            JButton btn = (JButton) e.getSource();

            for (int i = 0; i < btnColor.length; i++) {
                if(btn.equals(btnColor[i])) {
                    clearBtnColor();
                    btn.setText("X");
                    color = btn.getBackground();
                }
            }
        }
    }

    private void clearBtnColor() {
        for (int i = 0; i < btnColor.length; i++) {
            btnColor[i].setText("");
        }
    }

    private class EventScanner implements ActionListener {

        public void actionPerformed(ActionEvent e) {
            String data = e.getActionCommand();
            JButton btn = (JButton) e.getSource();

            if(data.equals("Line")) {
                resetButtons();
                btn.setEnabled(false);
                type = 2;
            }
            if(data.equals("Oval")) {
                resetButtons();
                btn.setEnabled(false);
                System.out.println("oval");
            }
            if(data.equals("Sircle")) {
                resetButtons();
                btn.setEnabled(false);
                type = 1;
            }
            if(data.equals("Square")) {
                resetButtons();
                btn.setEnabled(false);
                type = 3;
            }
            if(data.equals("Clear")) {
                resetButtons();
                btn.setEnabled(false);
                color = btnColor[0].getBackground();
                clearBtnColor();
                btnColor[0].setText("X");

                type = 0;
                shapes.clear();
                board.repaint();
            }
            if(data.equals("Print")) {
                PrinterJob printJob = PrinterJob.getPrinterJob();
                printJob.setPrintable(board);
                if (printJob.printDialog()) {
                    try {
                        printJob.print();
                    } catch (PrinterException pe) {
                        System.out.println("Error printing: " + pe);
                    }
                }
            }
        }

    }

    //Helper method to reset buttons
    private void resetButtons() {
        for (int i = 0; i < btns.length; i++) {
            btns[i].setEnabled(true);
        }
    }

    public static void main(String[] args) {
        new Paint();
    }
}