de.smits_net.games.framework.board

Class Board

java.lang.Object

java.awt.Component

java.awt.Container

javax.swing.JComponent

javax.swing.JPanel

de.smits_net.games.framework.board.Board

All Implemented Interfaces:

java.awt.event.KeyListener, java.awt.event.MouseListener, java.awt.image.ImageObserver, java.awt.MenuContainer, java.io.Serializable, java.lang.Runnable, java.util.EventListener, javax.accessibility.Accessible

public abstract class Board
extends javax.swing.JPanel
implements java.lang.Runnable, java.awt.event.KeyListener, java.awt.event.MouseListener

Base class for the game board. Games typically subclass this class and overwrite its methods to control the behavior of the game. The instances of the subclasses are embedded into a window which is provided by the class MainWindow.

This class creates the game thread, consumes the mouse and keyboard events and contains the game loop. The game loop periodically calls the updateGame(), drawBackground(Graphics) and drawGame(Graphics) methods.

A minimal game has to overwrite at least two methods:

• updateGame() to periodically update the state of all game objects.
• drawGame(Graphics) to draw the game objects.

When the game is over, the framework calls the drawGameOver(Graphics) to display a game over message. You have to overwrite this method to control this message.

By default, the game background is monochrome and in the color provided in the constructor. If you want to change this, overwrite the drawBackground(Graphics) method.

To ensure the desired performance of the game, the game loop measures the frames per second and skips the drawing if necessary to avoid a drop in the game performance. Nevertheless, the game update method is called.

If your game should use mouse or keyboard for interaction, you have to register a mouse or keyboard listener using the addMouseListener(MouseListener) or the addKeyListener(KeyListener) methods.

Author:

Thomas Smits

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class javax.swing.JPanel

javax.swing.JPanel.AccessibleJPanel

Nested classes/interfaces inherited from class javax.swing.JComponent

javax.swing.JComponent.AccessibleJComponent

Nested classes/interfaces inherited from class java.awt.Container

java.awt.Container.AccessibleAWTContainer

Nested classes/interfaces inherited from class java.awt.Component

java.awt.Component.AccessibleAWTComponent, java.awt.Component.BaselineResizeBehavior, java.awt.Component.BltBufferStrategy, java.awt.Component.FlipBufferStrategy

Field Summary

Fields

Modifier and Type	Field and Description
protected long	delay Time for each iteration (frame) in nano seconds.
protected java.awt.Dimension	dimension Dimension of the board.
protected boolean	gameRunning Indicator that the game is still running.
protected java.lang.Thread	thread The thread.

Fields inherited from class javax.swing.JComponent

listenerList, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW

Fields inherited from class java.awt.Component

accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface java.awt.image.ImageObserver

ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

Constructors

Constructor and Description
Board(int delay, java.awt.Dimension dimension, java.awt.Color color) Create a new board.
Board(int delay, int width, int height, java.awt.Color color) Create a new board.

Method Summary

Modifier and Type	Method and Description
void	addKeyListener(java.awt.event.KeyListener l)
void	addMouseListener(java.awt.event.MouseListener l)
void	addNotify()
protected void	centerText(java.awt.Graphics g, java.lang.String msg) Draw a text centered on the screen.
protected void	drawBackground(java.awt.Graphics g) Draw the background.
abstract void	drawGame(java.awt.Graphics g) The graphics output of the game.
protected void	drawGameOver(java.awt.Graphics g) Draw game over message.
java.awt.Dimension	getDimension() Returns the dimension of the board.
int	getHeight()
int	getWidth()
void	keyPressed(java.awt.event.KeyEvent e)
void	keyReleased(java.awt.event.KeyEvent e)
void	keyTyped(java.awt.event.KeyEvent e)
void	mouseClicked(java.awt.event.MouseEvent e)
void	mouseEntered(java.awt.event.MouseEvent e)
void	mouseExited(java.awt.event.MouseEvent e)
void	mousePressed(java.awt.event.MouseEvent e)
void	mouseReleased(java.awt.event.MouseEvent e)
void	run()
void	stopGame() Stops the game.
abstract boolean	updateGame() The game loop for the game logic.
protected void	writeText(java.awt.Graphics g, int x, int y, java.lang.String msg) Writes a text at the given position.

Methods inherited from class javax.swing.JPanel

getAccessibleContext, getUI, getUIClassID, paramString, setUI, updateUI

Methods inherited from class javax.swing.JComponent

addAncestorListener, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, getBorder, getBounds, getClientProperty, getComponentGraphics, getComponentPopupMenu, getConditionForKeyStroke, getDebugGraphicsOptions, getDefaultLocale, getFontMetrics, getGraphics, getInheritsPopupMenu, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getX, getY, grabFocus, hide, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingOrigin, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paint, paintBorder, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, addImpl, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, getMousePosition, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusDownCycle, validate, validateTree

Methods inherited from class java.awt.Component

action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, createImage, createImage, createVolatileImage, createVolatileImage, disableEvents, dispatchEvent, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

delay

protected final long delay

Time for each iteration (frame) in nano seconds.

dimension

protected final java.awt.Dimension dimension

Dimension of the board.

gameRunning

protected volatile boolean gameRunning

Indicator that the game is still running.

thread

protected java.lang.Thread thread

The thread.

Constructor Detail

Board

public Board(int delay,
             java.awt.Dimension dimension,
             java.awt.Color color)

Create a new board.

Parameters:

delay - delay between two frames in milliseconds

dimension - dimension of the board

color - background color of the board

Board

public Board(int delay,
             int width,
             int height,
             java.awt.Color color)

Create a new board.

Parameters:

delay - delay between two frames in milliseconds

width - width of the board in pixel

height - height of the board in pixel

color - background color of the board

Method Detail

addKeyListener

public final void addKeyListener(java.awt.event.KeyListener l)

Overrides:

addKeyListener in class java.awt.Component

addMouseListener

public final void addMouseListener(java.awt.event.MouseListener l)

Overrides:

addMouseListener in class java.awt.Component

addNotify

public void addNotify()

Overrides:

addNotify in class javax.swing.JComponent

See Also:

JComponent.addNotify()

centerText

protected final void centerText(java.awt.Graphics g,
                                java.lang.String msg)

Draw a text centered on the screen.

Parameters:

g - the graphics context

msg - the message to be shown

drawBackground

protected void drawBackground(java.awt.Graphics g)

Draw the background. The default implementation clears the background with the current background color.

Parameters:

g - the graphics context

drawGame

public abstract void drawGame(java.awt.Graphics g)

The graphics output of the game. This method is called periodically by the framework to draw the game graphics.

Parameters:

g - Graphics context.

drawGameOver

protected void drawGameOver(java.awt.Graphics g)

Draw game over message.

Parameters:

g - the graphics context

getDimension

public final java.awt.Dimension getDimension()

Returns the dimension of the board.

Returns:

the dimension

getHeight

public final int getHeight()

Overrides:

getHeight in class javax.swing.JComponent

See Also:

JComponent.getHeight()

getWidth

public final int getWidth()

Overrides:

getWidth in class javax.swing.JComponent

See Also:

JComponent.getWidth()

keyPressed

public void keyPressed(java.awt.event.KeyEvent e)

Specified by:

keyPressed in interface java.awt.event.KeyListener

See Also:

KeyListener.keyPressed(java.awt.event.KeyEvent)

keyReleased

public void keyReleased(java.awt.event.KeyEvent e)

Specified by:

keyReleased in interface java.awt.event.KeyListener

See Also:

KeyListener.keyReleased(java.awt.event.KeyEvent)

keyTyped

public void keyTyped(java.awt.event.KeyEvent e)

Specified by:

keyTyped in interface java.awt.event.KeyListener

See Also:

KeyListener.keyTyped(java.awt.event.KeyEvent)

mouseClicked

public void mouseClicked(java.awt.event.MouseEvent e)

Specified by:

mouseClicked in interface java.awt.event.MouseListener

See Also:

MouseListener.mouseClicked(java.awt.event.MouseEvent)

mouseEntered

public void mouseEntered(java.awt.event.MouseEvent e)

Specified by:

mouseEntered in interface java.awt.event.MouseListener

See Also:

MouseListener.mouseEntered(java.awt.event.MouseEvent)

mouseExited

public void mouseExited(java.awt.event.MouseEvent e)

Specified by:

mouseExited in interface java.awt.event.MouseListener

See Also:

MouseListener.mouseExited(java.awt.event.MouseEvent)

mousePressed

public void mousePressed(java.awt.event.MouseEvent e)

Specified by:

mousePressed in interface java.awt.event.MouseListener

See Also:

MouseListener.mousePressed(java.awt.event.MouseEvent)

mouseReleased

public void mouseReleased(java.awt.event.MouseEvent e)

Specified by:

mouseReleased in interface java.awt.event.MouseListener

See Also:

MouseListener.mouseReleased(java.awt.event.MouseEvent)

run

public final void run()

Specified by:

run in interface java.lang.Runnable

See Also:

Runnable.run()

stopGame

public void stopGame()

Stops the game.

updateGame

public abstract boolean updateGame()

The game loop for the game logic. This method will be called periodically be the framework to execute the game. All game actions must be triggered from this loop.

Returns:

true if the game should continue, otherwise false

writeText

protected final void writeText(java.awt.Graphics g,
                               int x,
                               int y,
                               java.lang.String msg)

Writes a text at the given position.

Parameters:

g - graphics context

x - x position of the text

y - y position of the text

msg - the message to be drawn