Class Whiteboard

java.lang.Object

java.awt.Component

java.awt.Container

java.awt.Panel

java.applet.Applet

org.jgroups.demos.wb.Whiteboard

All Implemented Interfaces:

ActionListener, ComponentListener, FocusListener, ImageObserver, MenuContainer, Serializable, EventListener, Accessible, MembershipListener, MessageListener

public class Whiteboard
extends Applet
implements ActionListener, MessageListener, MembershipListener, ComponentListener, FocusListener

Shared whiteboard: members are represented by rectangles that contain their names and the OS/arch of the machine they are working on. The boxes can be moved by anyone and by clicking on them, messages can be sent to specific or all members. Whiteboard is both an application and an applet.

Author:

Bela Ban

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class Applet

Applet.AccessibleApplet

Nested classes/interfaces inherited from class Panel

Panel.AccessibleAWTPanel

Nested classes/interfaces inherited from class Container

Container.AccessibleAWTContainer

Nested classes/interfaces inherited from class Component

Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

Fields

Modifier and Type	Field	Description
RpcDispatcher	disp
static final String	groupname

Fields inherited from class Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface ImageObserver

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

Constructor Summary

Constructors

Constructor	Description
Whiteboard()
Whiteboard(String properties)

Method Summary

Modifier and Type	Method	Description
void	actionPerformed(ActionEvent e)
void	addNode(String lbl, Address addr, int xloc, int yloc)
void	block()	Called (usually by the FLUSH protocol), as an indication that the member should stop sending messages.
void	componentHidden(ComponentEvent e)
void	componentMoved(ComponentEvent e)
void	componentResized(ComponentEvent e)
void	componentShown(ComponentEvent e)
void	destroy()
void	displayMessage(String sender, String msg)
void	focusGained(FocusEvent e)
void	focusLost(FocusEvent e)
byte[]	getState()	Answers the group state; e.g., when joining.
void	init()
static void	main(String[] args)
void	moveNode(Node n)
void	receive(Message m)	Called when a message is received.
void	removeNode(Object addr)
void	repaint()
void	setState(byte[] new_state)	Sets the group state; e.g., when joining.
void	suspect(Address obj)	Called whenever a member is suspected of having crashed, but has not yet been excluded.
void	viewAccepted(View v)	Called when a change in membership has occurred.

Methods inherited from class Applet

getAccessibleContext, getAppletContext, getAppletInfo, getAudioClip, getAudioClip, getCodeBase, getDocumentBase, getImage, getImage, getLocale, getParameter, getParameterInfo, isActive, isValidateRoot, newAudioClip, play, play, resize, resize, setStub, showStatus, start, stop

Methods inherited from class Panel

addNotify

Methods inherited from class Container

add, add, add, add, add, addContainerListener, addImpl, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getAlignmentX, getAlignmentY, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getInsets, getLayout, getListeners, getMaximumSize, getMinimumSize, getMousePosition, getPreferredSize, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paint, paintComponents, paramString, preferredSize, print, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, removeNotify, setComponentZOrder, setFocusCycleRoot, setFocusTraversalKeys, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setFont, setLayout, transferFocusDownCycle, update, validate, validateTree

Methods inherited from class Component

action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBaseline, getBaselineResizeBehavior, getBounds, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocation, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, printAll, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, requestFocus, requestFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, requestFocusInWindow, reshape, revalidate, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeysEnabled, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setMixingCutoutShape, setName, setPreferredSize, setSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle

Methods inherited from class Object

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

Field Details

disp

public RpcDispatcher disp

groupname

public static final String groupname

See Also:

• Constant Field Values

Constructor Details

Whiteboard

public Whiteboard()

Whiteboard

public Whiteboard(String properties)

Method Details

receive

public void receive(Message m)

Description copied from interface: MessageListener

Called when a message is received.

Specified by:

receive in interface MessageListener

Parameters:

m -

getState

public byte[] getState()

Description copied from interface: MessageListener

Answers the group state; e.g., when joining.

Specified by:

getState in interface MessageListener

Returns:

byte[]

setState

public void setState(byte[] new_state)

Description copied from interface: MessageListener

Sets the group state; e.g., when joining.

Specified by:

setState in interface MessageListener

Parameters:

new_state -

init

public void init()

Overrides:

init in class Applet

destroy

public void destroy()

Overrides:

destroy in class Applet

repaint

public void repaint()

Overrides:

repaint in class Component

actionPerformed

public void actionPerformed(ActionEvent e)

Specified by:

actionPerformed in interface ActionListener

viewAccepted

public void viewAccepted(View v)

Description copied from interface: MembershipListener

Called when a change in membership has occurred. No long running actions or sending of messages should be done in this callback. If some long running action needs to be performed, it should be done in a separate thread.

Note that on reception of the first view (a new member just joined), the channel will not yet be in the connected state. This only happens when Channel.connect(String) returns.

Specified by:

viewAccepted in interface MembershipListener

suspect

public void suspect(Address obj)

Description copied from interface: MembershipListener

Called whenever a member is suspected of having crashed, but has not yet been excluded.

Specified by:

suspect in interface MembershipListener

block

public void block()

Description copied from interface: MembershipListener

Called (usually by the FLUSH protocol), as an indication that the member should stop sending messages. Any messages sent after returning from this callback might get blocked by the FLUSH protocol. When the FLUSH protocol is done, and messages can be sent again, the FLUSH protocol will simply unblock all pending messages. If a callback for unblocking is desired, implement ExtendedMembershipListener.unblock(). Note that block() is the equivalent of reception of a BlockEvent in the pull mode.

Specified by:

block in interface MembershipListener

moveNode

public void moveNode(Node n)

addNode

public void addNode(String lbl,
 Address addr,
 int xloc,
 int yloc)

removeNode

public void removeNode(Object addr)

displayMessage

public void displayMessage(String sender,
 String msg)

componentResized

public void componentResized(ComponentEvent e)

Specified by:

componentResized in interface ComponentListener

componentMoved

public void componentMoved(ComponentEvent e)

Specified by:

componentMoved in interface ComponentListener

componentShown

public void componentShown(ComponentEvent e)

Specified by:

componentShown in interface ComponentListener

componentHidden

public void componentHidden(ComponentEvent e)

Specified by:

componentHidden in interface ComponentListener

focusGained

public void focusGained(FocusEvent e)

Specified by:

focusGained in interface FocusListener

focusLost

public void focusLost(FocusEvent e)

Specified by:

focusLost in interface FocusListener

main

public static void main(String[] args)