eventweb

Class TvIoWwgt

java.lang.Object

java.awt.Component

java.awt.Container

java.awt.Panel

java.applet.Applet

eventweb.TvIoWwgt

All Implemented Interfaces:

java.awt.image.ImageObserver, java.awt.MenuContainer, java.io.Serializable, javax.accessibility.Accessible

public class TvIoWwgt
extends java.applet.Applet

Http Tag-Value networking applet.

Provides networking for JavaScript in Html pages.

Notes:
IE Javascript limitations (IE 5.x, 6.x):
1 IE is unable to recognize String arrays returned from java.
2 IE sometimes interprets a null string returned from java as an empty string.

Version:

1.7.1 05/10/15

Author:

Stephen W. Thompson

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.applet.Applet

java.applet.Applet.AccessibleApplet

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

java.awt.Panel.AccessibleAWTPanel

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 static java.awt.Color	closedBgColor Connection closed background color
static java.lang.String[]	DEP_LIST Class dependencies
protected static java.awt.Color	errorBgColor Error background color
protected static java.awt.Color	goodBgColor Good connection background color
protected static java.awt.Color	initBgColor Applet initializing background color
static int	MODE_CHANNEL EventWeb Backchannel
static int	MODE_GET HTTP Get
static int	MODE_NONE No mode specified
static int	MODE_POST HTTP Post
static int	STS_CLOSED Closed by client
static int	STS_CLOSING (Client) Closing connection
static int	STS_DISCONN Disconnected by server
static int	STS_ERROR Error condition
static int	STS_INIT Initializing
static int	STS_LISTENING Listening for messages
static int	STS_OPEN Open to send and receive
static int	STS_OPENING Opening connection
static int	STS_WARNING Warning condition
static java.lang.String	VERSION Class version
protected static java.awt.Color	warningBgColor Warning background color

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

Constructors

Constructor and Description
TvIoWwgt() Create a new TvIoWwgt.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	buildCmpMsg(java.lang.String tag, java.lang.String value) Add a tag-value pair to the current compound message.
boolean	closeUrl() Disconnect from URL.
boolean	dataIsAvailable() Determine if there is data available.
void	destroy() Release all non-memory resources held by the applet.
java.lang.String	getAppletInfo() Get information about this applet.
java.lang.String[][]	getParameterInfo() Get parameter info for this applet.
int	getStatus() Get connection status
java.lang.String	getTag() Get the tag from the next message with an unread tag.
java.lang.String	getValue() Get the value from the next message with an unread value.
void	init() Initialize the applet.
boolean	isWaitingForData() Determine if processing is needed.
boolean	openUrl(java.lang.String urlName) Connect to URL in default communication mode
boolean	openUrl(java.lang.String urlName, int mode) Connect to URL The URL is opened asynchronously.
boolean	openUrlSynch(java.lang.String urlName, int mode) Connect to URL Synchronously.
boolean	recHasMore() Determine if there is more data in the current record.
static java.lang.String	removeTags(java.lang.String sVal) Remove tags from HTML.
boolean	retry() Retry a lost URL connection.
boolean	sendCmpMsg() Send the current commpound message and then clear it.
boolean	sendMsg(java.lang.String tag, java.lang.String value) Send a message with a single tag-value pair.
protected void	startThread() Start the listener thread execution loop.
protected void	stopThread() Stop the listener thread execution loop.
static java.lang.String	textualizeHtml(java.lang.String sVal) Encode HTML so it will be displayed as plain text in a browser.

Methods inherited from class java.applet.Applet

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

Methods inherited from class java.awt.Panel

addNotify

Methods inherited from class java.awt.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 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, 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, getPeer, 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, repaint, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, reshape, revalidate, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeysEnabled, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setName, setPreferredSize, setSize, setSize, setVisible, 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

VERSION

public static final java.lang.String VERSION

Class version

DEP_LIST

public static final java.lang.String[] DEP_LIST

Class dependencies

MODE_NONE

public static final int MODE_NONE

No mode specified

See Also:

Constant Field Values

MODE_GET

public static final int MODE_GET

HTTP Get

See Also:

Constant Field Values

MODE_POST

public static final int MODE_POST

HTTP Post

See Also:

Constant Field Values

MODE_CHANNEL

public static final int MODE_CHANNEL

EventWeb Backchannel

See Also:

Constant Field Values

STS_ERROR

public static final int STS_ERROR

Error condition

See Also:

Constant Field Values

STS_WARNING

public static final int STS_WARNING

Warning condition

See Also:

Constant Field Values

STS_INIT

public static final int STS_INIT

Initializing

See Also:

Constant Field Values

STS_DISCONN

public static final int STS_DISCONN

Disconnected by server

See Also:

Constant Field Values

STS_CLOSED

public static final int STS_CLOSED

Closed by client

See Also:

Constant Field Values

STS_CLOSING

public static final int STS_CLOSING

(Client) Closing connection

See Also:

Constant Field Values

STS_OPENING

public static final int STS_OPENING

Opening connection

See Also:

Constant Field Values

STS_OPEN

public static final int STS_OPEN

Open to send and receive

See Also:

Constant Field Values

STS_LISTENING

public static final int STS_LISTENING

Listening for messages

See Also:

Constant Field Values

initBgColor

protected static final java.awt.Color initBgColor

Applet initializing background color

closedBgColor

protected static final java.awt.Color closedBgColor

Connection closed background color

goodBgColor

protected static final java.awt.Color goodBgColor

Good connection background color

warningBgColor

protected static final java.awt.Color warningBgColor

Warning background color

errorBgColor

protected static final java.awt.Color errorBgColor

Error background color

Constructor Detail

TvIoWwgt

public TvIoWwgt()

Create a new TvIoWwgt.

Method Detail

textualizeHtml

public static java.lang.String textualizeHtml(java.lang.String sVal)

Encode HTML so it will be displayed as plain text in a browser. Tags will be displayed rather than interpreted.

Parameters:

sVal - The (HTML) string to be encoded

Returns:

Encoded HTML string

removeTags

public static java.lang.String removeTags(java.lang.String sVal)

Remove tags from HTML.

Parameters:

sVal - The (HTML) string to be processed

Returns:

Plain text string

init

public void init()

Initialize the applet.
(Called at startup after constructor.)

Overrides:

init in class java.applet.Applet

destroy

public void destroy()

Release all non-memory resources held by the applet.
(Called when the applet is about to be unloaded.)

Overrides:

destroy in class java.applet.Applet

getAppletInfo

public java.lang.String getAppletInfo()

Get information about this applet.

Overrides:

getAppletInfo in class java.applet.Applet

Returns:

String containing applet information

getParameterInfo

public java.lang.String[][] getParameterInfo()

Get parameter info for this applet.

Overrides:

getParameterInfo in class java.applet.Applet

Returns:

Array of parameter descriptions
A parameter description is an array of parameter, parameter type, default value

openUrl

public boolean openUrl(java.lang.String urlName)

Connect to URL in default communication mode

Parameters:

urlName - URL to connect to

Returns:

true, if the URL is opened successfully

openUrl

public boolean openUrl(java.lang.String urlName,
              int mode)

Connect to URL
The URL is opened asynchronously. This method returns before the open completes.

Parameters:

urlName - URL to connect to

mode - Communication mode for the channel

Returns:

true (Always returns true)

openUrlSynch

public boolean openUrlSynch(java.lang.String urlName,
                   int mode)

Connect to URL Synchronously.

Parameters:

urlName - URL to connect to

mode - Communication mode for the channel

Returns:

true, If the channel opens successfully

retry

public boolean retry()

Retry a lost URL connection.

Returns:

true, If the channel opens successfully

closeUrl

public boolean closeUrl()

Disconnect from URL.

Returns:

true, If the connection closes successfully

sendMsg

public boolean sendMsg(java.lang.String tag,
              java.lang.String value)

Send a message with a single tag-value pair.

Parameters:

tag - Tag for message

value - Value for message

Returns:

true, If the message is sent successfully

buildCmpMsg

public boolean buildCmpMsg(java.lang.String tag,
                  java.lang.String value)

Add a tag-value pair to the current compound message.

Parameters:

tag - Tag for pair to add to message

value - Value for pair to add to message

Returns:

true, If the pair was added successfully

sendCmpMsg

public boolean sendCmpMsg()

Send the current commpound message and then clear it.

Returns:

true, If the message is sent successfully

getTag

public java.lang.String getTag()

Get the tag from the next message with an unread tag.
This method is used in conjunction with getValue to obtain a tag-value pair. (It would be preferable to have a single method that would return a two element string array with tag and value, but some browsers do not handle that properly.)

Returns:

The tag

getValue

public java.lang.String getValue()

Get the value from the next message with an unread value.
(See note under getTag.)

Returns:

The value

isWaitingForData

public boolean isWaitingForData()

Determine if processing is needed.

Returns:

true, If applet is connected but has no data available.

dataIsAvailable

public boolean dataIsAvailable()

Determine if there is data available.

Returns:

true, if data is available

recHasMore

public boolean recHasMore()

Determine if there is more data in the current record.

Returns:

true, If more data is available

getStatus

public int getStatus()

Get connection status

Returns:

Current connection status. (One of the STS_ values.)

startThread

protected void startThread()

Start the listener thread execution loop.

stopThread

protected void stopThread()

Stop the listener thread execution loop.