org.jcsp.awt
Class ActiveFrame

java.lang.Object
  java.awt.Component
      java.awt.Container
          java.awt.Window
              java.awt.Frame
                  org.jcsp.awt.ActiveFrame

All Implemented Interfaces:

ImageObserver, MenuContainer, Serializable, Accessible, CSProcess

public class ActiveFrame
extends Frame
implements CSProcess

java.awt.Frame with a channel interface.

Process Diagram

Description

ActiveFrame is a process extension of java.awt.Frame with channels for run-time configuration and event notification. The event channels should be connected to one or more application-specific server processes (instead of registering a passive object as a Listener to this component).

All channels are optional. The configure and event channels are settable from a constructor. The event channel delivers a WindowEvent whenever one is generated on the ActiveFrame. Other event channels can be added to notify the occurrence of any other events the component generates (by calling the appropriate addXXXEventChannel method before the process is run). Messages can be sent down the configure channel at any time to configure the component. See the table below for details.

All channels are managed by independent internal handler processes. It is, therefore, safe for a serial application process both to service an event channel and configure the component -- no deadlock can occur.

IMPORTANT: it is essential that event channels from this process are always serviced -- otherwise the Java Event Thread will be blocked and the GUI will stop responding. A simple way to guarantee this is to use channels configured with overwriting buffers. For example:

   final One2OneChannel myWindowEvent = Channel.one2one (new OverWriteOldestBuffer (n));
   final One2OneChannel myMouseEvent = Channel.one2one (new OverWriteOldestBuffer (n));
 
   final ActiveFrame myFrame = new ActiveFrame (myWindowEvent.out ());
   myFrame.addMouseEventChannel (myMouseEvent.out ());
 

This will ensure that the Java Event Thread will never be blocked. Slow or inattentive readers may miss rapidly generated events, but the n most recent events will always be available.

Channel Protocols

Input Channels
configure	Boolean	If this is the Boolean.TRUE object, the frame is made visible If this is the Boolean.FALSE object, the frame is made invisible Other Boolean objects are ignored
	ActiveFrame.Configure	Invoke the user-defined Configure.configure method on the frame.
Output Channels
event	WindowEvent	The WindowEvent generated by the component
containerEvent	ContainerEvent	See the addContainerEventChannel method.
componentEvent	ComponentEvent	See the addComponentEventChannel method.
focusEvent	FocusEvent	See the addFocusEventChannel method.
keyEvent	KeyEvent	See the addKeyEventChannel method.
mouseEvent	MouseEvent	See the addMouseEventChannel method.
mouseMotionEvent	MouseEvent	See the addMouseMotionEventChannel method.

Example

 import java.awt.*;
 import java.awt.event.*;
 import org.jcsp.lang.*;
 import org.jcsp.util.*;
 import org.jcsp.awt.*;
 
 public class ActiveFrameButtonExample {
 
   public static void main (String argv[]) {
 
     final Any2OneChannel windowEvent = Channel.any2one (new OverWriteOldestBuffer (10));
 
     final ActiveFrame frame =
       new ActiveFrame (null, windowEvent.out (), "ActiveButton Example");
 
     final String[] label = {"Hello World", "Rocket Science", "CSP",
                             "Monitors", "Ignore Me", "Goodbye World"};
 
     final Any2OneChannel buttonEvent = Channel.any2one (new OverWriteOldestBuffer (10));
 
     final ActiveButton[] button = new ActiveButton[label.length];
     for (int i = 0; i < label.length; i++) {
       button[i] = new ActiveButton (null, buttonEvent.out (), label[i]);
     }
 
     frame.setSize (300, 200);
     frame.setLayout (new GridLayout (label.length/2, 2));
     for (int i = 0; i < label.length; i++) {
       frame.add (button[i]);
     }
     frame.setVisible (true);
 
     new Parallel (
       new CSProcess[] {
         new Parallel (button),
         new CSProcess () {                 // respond to window events
           public void run () {
             boolean running = true;
             while (running) {
               final WindowEvent w = (WindowEvent) windowEvent.in ().read ();
               System.out.println ("Window event: " + w);
               running = (w.getID () != WindowEvent.WINDOW_CLOSING);
             }
             frame.setVisible (false);
             System.exit (0);
           }
         },
         new CSProcess () {                 // respond to button events
           public void run () {
             boolean running = true;
             while (running) {
               final String s = (String) buttonEvent.in ().read ();
               System.out.println ("Button `" + s + "' pressed ...");
               running = (s != label[label.length - 1]);
             }
             frame.setVisible (false);
             System.exit (0);
           }
         }
       }
     ).run ();
 
   }
 
 }
 

Author:

P.D. Austin and P.H. Welch

See Also:

ActiveClosingFrame, Frame, ContainerEvent, ComponentEvent, FocusEvent, KeyEvent, MouseEvent, OverWriteOldestBuffer, Serialized Form

Nested Class Summary

static interface

ActiveFrame.Configure This enables general configuration of this component.

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

Frame.AccessibleAWTFrame

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

Window.AccessibleAWTWindow

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

Container.AccessibleAWTContainer

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

Component.AccessibleAWTComponent, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

Fields inherited from class java.awt.Frame

CROSSHAIR_CURSOR, DEFAULT_CURSOR, E_RESIZE_CURSOR, HAND_CURSOR, ICONIFIED, MAXIMIZED_BOTH, MAXIMIZED_HORIZ, MAXIMIZED_VERT, MOVE_CURSOR, N_RESIZE_CURSOR, NE_RESIZE_CURSOR, NORMAL, NW_RESIZE_CURSOR, S_RESIZE_CURSOR, SE_RESIZE_CURSOR, SW_RESIZE_CURSOR, TEXT_CURSOR, W_RESIZE_CURSOR, WAIT_CURSOR

Fields inherited from class java.awt.Component

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

ActiveFrame()
Constructs a new ActiveFrame with no title and no configuration or event channels.

ActiveFrame(ChannelInput configure, ChannelOutput event)
Constructs a new ActiveFrame with configuration and event channels, but no title.

ActiveFrame(ChannelInput configure, ChannelOutput event, String title)
Constructs a new ActiveFrame with configuration and event channels and a title.

ActiveFrame(String title)
Constructs a new ActiveFrame with a title but no configuration or event channels.

Method Summary

void	addComponentEventChannel(ChannelOutput componentEvent) Add a new channel to this component that will be used to notify that a ComponentEvent has occurred.
void	addContainerEventChannel(ChannelOutput containerEvent) Add a new channel to this component that will be used to notify that a ContainerEvent has occurred.
void	addFocusEventChannel(ChannelOutput focusEvent) Add a new channel to this component that will be used to notify that a FocusEvent has occurred.
void	addKeyEventChannel(ChannelOutput keyEvent) Add a new channel to this component that will be used to notify that a KeyEvent has occurred.
void	addMouseEventChannel(ChannelOutput mouseEvent) Add a new channel to this component that will be used to notify that a MouseEvent has occurred.
void	addMouseMotionEventChannel(ChannelOutput mouseMotionEvent) Add a new channel to this component that will be used to notify that a MouseMotionEvent has occurred.
void	run() The main body of this process.
void	setConfigureChannel(ChannelInput configure) Sets the configuration channel for this ActiveFrame.

Methods inherited from class java.awt.Frame

addNotify, finalize, getAccessibleContext, getCursorType, getExtendedState, getFrames, getIconImage, getMaximizedBounds, getMenuBar, getState, getTitle, isResizable, isUndecorated, paramString, remove, removeNotify, setCursor, setExtendedState, setIconImage, setMaximizedBounds, setMenuBar, setResizable, setState, setTitle, setUndecorated

Methods inherited from class java.awt.Window

addPropertyChangeListener, addPropertyChangeListener, addWindowFocusListener, addWindowListener, addWindowStateListener, applyResourceBundle, applyResourceBundle, createBufferStrategy, createBufferStrategy, dispose, getBufferStrategy, getFocusableWindowState, getFocusCycleRootAncestor, getFocusOwner, getFocusTraversalKeys, getGraphicsConfiguration, getInputContext, getListeners, getLocale, getMostRecentFocusOwner, getOwnedWindows, getOwner, getToolkit, getWarningString, getWindowFocusListeners, getWindowListeners, getWindowStateListeners, hide, isActive, isAlwaysOnTop, isFocusableWindow, isFocusCycleRoot, isFocused, isLocationByPlatform, isShowing, pack, postEvent, processEvent, processWindowEvent, processWindowFocusEvent, processWindowStateEvent, removeWindowFocusListener, removeWindowListener, removeWindowStateListener, setAlwaysOnTop, setBounds, setCursor, setFocusableWindowState, setFocusCycleRoot, setLocationByPlatform, setLocationRelativeTo, show, toBack, toFront

Methods inherited from class java.awt.Container

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

Methods inherited from class java.awt.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, getBounds, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocation, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isPreferredSizeSet, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, prepareImage, prepareImage, printAll, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, setBackground, setBounds, setComponentOrientation, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeysEnabled, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setName, setPreferredSize, setSize, setSize, setVisible, show, size, toString, transferFocus, transferFocusUpCycle

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.awt.MenuContainer

getFont, postEvent

Constructor Detail

ActiveFrame

public ActiveFrame()

Constructs a new ActiveFrame with no title and no configuration or event channels.

ActiveFrame

public ActiveFrame(String title)

Constructs a new ActiveFrame with a title but no configuration or event channels.

Parameters:

title - the title for the frame.

ActiveFrame

public ActiveFrame(ChannelInput configure,
                   ChannelOutput event)

Constructs a new ActiveFrame with configuration and event channels, but no title.

Parameters:

configure - the channel for configuration events -- can be null if no configuration is required.

event - a WindowEvent will be output whenever it occurs -- can be null if no notification is required.

ActiveFrame

public ActiveFrame(ChannelInput configure,
                   ChannelOutput event,
                   String title)

Constructs a new ActiveFrame with configuration and event channels and a title.

Parameters:

configure - the channel for configuration events -- can be null if no configuration is required.

event - a WindowEvent will be output whenever it occurs -- can be null if no notification is required.

title - the title for the frame.

Method Detail

setConfigureChannel

public void setConfigureChannel(ChannelInput configure)

Sets the configuration channel for this ActiveFrame. This method overwrites any configuration channel set in the constructor.

Parameters:

configure - the channel for configuration events -- can be null if no configuration is required.

addContainerEventChannel

public void addContainerEventChannel(ChannelOutput containerEvent)

Add a new channel to this component that will be used to notify that a ContainerEvent has occurred. This should be used instead of registering a ContainerListener with the component. It is possible to add more than one Channel by calling this method multiple times If the channel passed is null, no action will be taken.

NOTE: This method must be called before this process is run.

Parameters:

containerEvent - the channel down which to send ContainerEvents.

addComponentEventChannel

public void addComponentEventChannel(ChannelOutput componentEvent)

Add a new channel to this component that will be used to notify that a ComponentEvent has occurred. This should be used instead of registering a ComponentListener with the component. It is possible to add more than one Channel by calling this method multiple times If the channel passed is null, no action will be taken.

NOTE: This method must be called before this process is run.

Parameters:

componentEvent - the channel down which to send ComponentEvents.

addFocusEventChannel

public void addFocusEventChannel(ChannelOutput focusEvent)

Add a new channel to this component that will be used to notify that a FocusEvent has occurred. This should be used instead of registering a FocusListener with the component. It is possible to add more than one Channel by calling this method multiple times If the channel passed is null, no action will be taken.

NOTE: This method must be called before this process is run.

Parameters:

focusEvent - the channel down which to send FocusEvents.

addKeyEventChannel

public void addKeyEventChannel(ChannelOutput keyEvent)

Add a new channel to this component that will be used to notify that a KeyEvent has occurred. This should be used instead of registering a KeyListener with the component. It is possible to add more than one Channel by calling this method multiple times If the channel passed is null, no action will be taken.

NOTE: This method must be called before this process is run.

Parameters:

keyEvent - the channel down which to send KeyEvents.

addMouseEventChannel

public void addMouseEventChannel(ChannelOutput mouseEvent)

Add a new channel to this component that will be used to notify that a MouseEvent has occurred. This should be used instead of registering a MouseListener with the component. It is possible to add more than one Channel by calling this method multiple times If the channel passed is null, no action will be taken.

NOTE: This method must be called before this process is run.

Parameters:

mouseEvent - the channel down which to send MouseEvents.

addMouseMotionEventChannel

public void addMouseMotionEventChannel(ChannelOutput mouseMotionEvent)

Add a new channel to this component that will be used to notify that a MouseMotionEvent has occurred. This should be used instead of registering a MouseMotionListener with the component. It is possible to add more than one Channel by calling this method multiple times If the channel passed is null, no action will be taken.

NOTE: This method must be called before this process is run.

Parameters:

mouseMotionEvent - the channel down which to send MouseMotionEvents.

run

public void run()

The main body of this process.

Specified by:

run in interface CSProcess