com.ibm.tspaces.examples.whiteboard
Class WhiteboardPanel

java.lang.Object
  |
  +--java.awt.Component
        |
        +--java.awt.Container
              |
              +--java.awt.Panel
                    |
                    +--com.ibm.tspaces.examples.whiteboard.WhiteboardPanel

public class WhiteboardPanel

extends java.awt.Panel

implements java.awt.event.MouseListener, java.awt.event.MouseMotionListener, Callback

The panel of the whiteboard. This handles the panel where the lines and points are drawn. All of the TSpaces handling is done inside this object. It implements the Tuplespace Callback interface which gets control everytime a matching request is issued to TupleSpace.

Author:

Matthias Eichstaedt, John Thomas

See Also:

Serialized Form

Field Summary

protected static java.awt.Color	BACKGROUND_COLOR
protected boolean	EraseFlag
protected boolean	Failed
protected java.lang.String	Host This is the Host where the TupleSpace Server is running
static int	LINES
protected boolean	NotActive
static int	POINTS
protected int	Port This is the port number for the TupleSpace server.
protected TupleSpace	TSServer This holds a reference to the current TupleSpace.

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Constructor Summary

WhiteboardPanel()
The constructor

Method Summary

boolean	call(java.lang.String eventName_, java.lang.String tsName_, int sequenceNumber_, SuperTuple tuple_, boolean isException_) Process the callback from the server that notifies us when anyone (including ourselfes) writes to the Whiteboard TupleSpace.
void	erase() Erase the lines that the User has drawn since last Publish.
void	eraseAll() Global Erase of the whiteboard.
void	exitcmd()
void	init(Whiteboard caller) TupleSpace Initiallization routine.
void	mouseClicked(java.awt.event.MouseEvent e) The mouse button was clicked.
void	mouseDragged(java.awt.event.MouseEvent e) The mouse was dragged.
void	mouseEntered(java.awt.event.MouseEvent e) The mouse entered this panel.
void	mouseExited(java.awt.event.MouseEvent e) The mouse left this panel.
void	mouseMoved(java.awt.event.MouseEvent e) The mouse was moved.
void	mousePressed(java.awt.event.MouseEvent e) The mouse button was pressed.
void	mouseReleased(java.awt.event.MouseEvent e) The mouse button was released.
void	paint(java.awt.Graphics g) Paints the panel.
void	paint(java.awt.Graphics g, java.util.Vector lines, java.util.Vector colors) Paints the panel based on the vectos of lines and colors.
void	publish() Publish the current content to tuplespace.
void	removeAll() This is called our parent (Whiteboard) gets a applet destroy() event.
void	setDrawMode(int mode) Set the draw mode.
void	term() This is called when the windowClosing event arrives.

Methods inherited from class java.awt.Panel

addNotify

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, addImpl, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getAlignmentX, getAlignmentY, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getInsets, getLayout, getMaximumSize, getMinimumSize, getPreferredSize, insets, invalidate, isAncestorOf, layout, list, list, locate, minimumSize, paintComponents, paramString, preferredSize, print, printComponents, processContainerEvent, processEvent, remove, remove, removeContainerListener, removeNotify, setCursor, setFont, setLayout, update, validate, validateTree

Methods inherited from class java.awt.Component

action, add, addComponentListener, addFocusListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addPropertyChangeListener, addPropertyChangeListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, firePropertyChange, getBackground, getBounds, getBounds, getColorModel, getComponentOrientation, getCursor, getDropTarget, getFont, getFontMetrics, getForeground, getGraphics, getHeight, getInputContext, getInputMethodRequests, getLocale, getLocation, getLocation, getLocationOnScreen, getName, getParent, getPeer, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, isDisplayable, isDoubleBuffered, isEnabled, isFocusTraversable, isLightweight, isOpaque, 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, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, remove, removeComponentListener, removeFocusListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, reshape, resize, resize, setBackground, setBounds, setBounds, setComponentOrientation, setDropTarget, setEnabled, setForeground, setLocale, setLocation, setLocation, setName, setSize, setSize, setVisible, show, show, size, toString, transferFocus

Methods inherited from class java.lang.Object

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

Field Detail

LINES

public static final int LINES

POINTS

public static final int POINTS

BACKGROUND_COLOR

protected static java.awt.Color BACKGROUND_COLOR

TSServer

protected TupleSpace TSServer

This holds a reference to the current TupleSpace.

Host

protected java.lang.String Host

This is the Host where the TupleSpace Server is running

Port

protected int Port

This is the port number for the TupleSpace server. The TupleSpace HTTP Server is at this port +1

EraseFlag

protected boolean EraseFlag

NotActive

protected boolean NotActive

Failed

protected boolean Failed

Constructor Detail

WhiteboardPanel

public WhiteboardPanel()

The constructor

Method Detail

init

public void init(Whiteboard caller)

TupleSpace Initiallization routine. This will setup to access TupleSpace and register to be informed when anyone writes a "Whiteboard" tuple to the "Whiteboard" tuplespace. It will then get all the current Tuples and paint them. TupleSpace contains the all of the whiteboard tuples that have been written up to this time. We want to read in and process all of them. We use the scan method for this and get back a tuple that is a list of the tuples.

See Also:

TupleSpace, Tuple, Field

term

public void term()

This is called when the windowClosing event arrives. We will tell the server that we are going away by issuing the cleanup() command.

See Also:

TupleSpace.cleanup()

removeAll

public void removeAll()

This is called our parent (Whiteboard) gets a applet destroy() event. We will tell the server that we are going away by issuing the term() command.

Overrides:

removeAll in class java.awt.Container

publish

public void publish()

Publish the current content to tuplespace. This will write the vector of lines and colors that the user has created since the last publish. It will then start a new set of lines and colors. Since we will be informed of our own write in the callback, we will let the callback update the set of all lines.

erase

public void erase()

Erase the lines that the User has drawn since last Publish.

eraseAll

public void eraseAll()

Global Erase of the whiteboard. This will write a empty vector of lines and colors to tuplespace. This will be treated as an erase command by other clients that receive the request. We will also delete all of the old lines and points that have been accumulating in the TupleSpace. Since we will be informed of this in the callback, we will let the callback update the set of all lines. We won't worry about problems caused by requests arriving at the the server and clients in different orders.

exitcmd

public void exitcmd()

call

public boolean call(java.lang.String eventName_,
                    java.lang.String tsName_,
                    int sequenceNumber_,
                    SuperTuple tuple_,
                    boolean isException_)

Process the callback from the server that notifies us when anyone (including ourselfes) writes to the Whiteboard TupleSpace. If we get back 2 empty vectors, then this was an erase request from one of our users. Otherwise, the 2 vectors are the lines/points and colors that one of our users is publishing

Specified by:

call in interface Callback

Parameters:

eventName_ - the name of the event command that caused this call, that is the name of the client side command of the thread that registered this call, e.g., in the case of a read, this would be TupleSpace.READ, **not** TupleSpace.WRITE which is the corresponding command that caused the actaul event.

tsName_ - the name of the tuple space this command was executed on.

sequenceNumber_ - the sequenceNumber for this event/command

tuple_ - the returned tuple or a Tuple with an exception inside

isException_ - was the command processed normaly or was there an exception

Returns:

true if this is the last call this sequence # should be getting otherwise false

paint

public void paint(java.awt.Graphics g)

Paints the panel. The real paint method is called first for the objects that this user has generated, and then for a vector of objects that have been recieved form TupleSpace. If an Erase request was received from TupleSpace then the EraseFlag was set and we will erase the window before proceeding.

Overrides:

paint in class java.awt.Container

Parameters:

g - - the graphics context

paint

public void paint(java.awt.Graphics g,
                  java.util.Vector lines,
                  java.util.Vector colors)

Paints the panel based on the vectos of lines and colors.

Parameters:

g - - the graphics context

lines - - A vector of Rectangle objects

colors - - A vector of color objects.

setDrawMode

public void setDrawMode(int mode)

Set the draw mode.

Parameters:

mode - - the draw mode

mouseDragged

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

The mouse was dragged.

Specified by:

mouseDragged in interface java.awt.event.MouseMotionListener

Parameters:

e - - the mouse event

mouseMoved

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

The mouse was moved.

Specified by:

mouseMoved in interface java.awt.event.MouseMotionListener

Parameters:

e - - the mouse event

mousePressed

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

The mouse button was pressed.

Specified by:

mousePressed in interface java.awt.event.MouseListener

Parameters:

e - - the mouse event

mouseReleased

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

The mouse button was released.

Specified by:

mouseReleased in interface java.awt.event.MouseListener

Parameters:

e - - the mouse event

mouseEntered

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

The mouse entered this panel.

Specified by:

mouseEntered in interface java.awt.event.MouseListener

Parameters:

e - - the mouse event

mouseExited

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

The mouse left this panel.

Specified by:

mouseExited in interface java.awt.event.MouseListener

Parameters:

e - - the mouse event

mouseClicked

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

The mouse button was clicked.

Specified by:

mouseClicked in interface java.awt.event.MouseListener

Parameters:

e - - the mouse event