The standalone version of this demo uses a URL that points to a static file containing a snapshot of stock transaction information for some specific historical date. The data format of this static file is the same as the format of the data that the applets would receive from a live stock server if one existed on the Web. The difference is that the static file will reach an EOF (End of File), whereas a live feed would never end, staying open indefinitely.

The live version of this demo connects to an HTTP server with a script that queries a live (or 15 minute delayed) stock quote feed and sends information back to the applet in the stock data format. It leaves the connection open so that more quote information can be sent back as time progresses and new quotes become known.

These applets were originally written to demonstrate how Java applets can be used to customize the presentation of information for a a web site. The applets are used internally behind the Sun firewall with an HTTP server that generates live data. Since we do not have permission to publish this live data outside our firewall, we have made the applets capable of reading that same information from static files on our external Web server so that you can see what they look like.

The applets are not meant to be commercial quality as you see them here and Sun has no desire to make a product out of this demo itself. If a financial institution wishes to provide live data for these applets, the institution may use these applets as a starting point for such a service, provided that is made available free of charge.

The applets are compiled from 5 different source files:

• StockTicker.java
• QuoteChart.java
• ClosedCaption.java
• StockStreamParser.java
• StockWatcher.java

The standalone version of the applets you see here rely on 5 different data files for their information:

• The StockTicker snapshot data.
• The SUNW history data for the quote chart.
• The Netscape history data for the quote chart.
• The Neato history data for the quote chart.
• The closed caption file.

The entire demo is available in compressed tar format (120K) for easy downloading.

Stock Applet Parameters

Stock Ticker applet parameters

Example:

<applet codebase=classes code=StockTicker.class width=500 height=20>
    <param name=stocks value="SUNW|HWP|SGI|MSFT|INTC|IBM|DEC|CY|ADBE|AAPL|SPX|ZRA|NSCP|NEATO">
    <param name=staticdata value=tickerdata>
    <param name=fudge value=true>
</applet>

This applet can use any of the following 11 parameters:

stocks

The list of stock symbols to display quotes for. Each symbol is separated from the next by a vertical bar or pipe character, '|'.

scrollt

The time in seconds the applet should take to scroll one entire set of quotes through the ticker display.

deltat

The time in milliseconds to wait between scroll updates. This parameter controls how smooth or "jumpy" the scrolling is.

freshfg

The color to use to display fresh quotes representing new information not previously displayed.

stalefg

The color to use to display old quotes that have been scrolled across the display at least once previously.

errorfg

The color to use to display quotes which the server has been unable to fetch or verify for more than 15 minutes.

bgcolor

The background color of the scrolling ticker.

livedata

The URL to use to fetch data from a live source.

staticdata

The URL to use to fetch data from a static file.

fudge

A boolean controlling whether or not the server should fudge new quotes if it is unable to read real quotes from the stock feed (used to show dynamic data in demo situations - deprecated).

delay

The time in seconds between generating fake quotes when fudge mode is activated.

Quote History Chart applet parameters

Example:

<applet codebase=classes code=QuoteChart.class width=190 height=100>
    <param name=staticdata value=chartdata%>
    <param name=stock value=NSCP>
    <param name=label value=Netscape>
    <param name=history value="8h">
    <param name=fudge value=true>
</applet>

This applet can use any of the following 14 parameters:

stock

The stock symbol to display history information for.

history

How much historical data to display in the graph window, with units (d - days, h - hours, m - minutes, s - seconds).

label

The text to use to label the graph instead of the (often cryptic) stock symbol.

graphborder

The size in pixels of the border around the graph.

graphbg

The color of the background of the graph.

graphfg

The color of the lines used to graph the quote data.

quotefg

The color to display the current quote at the top of the graph in.

zerofg

The color for the baseline of the graph (for stocks, the closing quote from the previous day is the baseline, not 0).

tickfg

The color to draw the horizontal tick marks which divide up the graph to provide a sense of scale.

legendfg

The color to draw the numbers representing the values that would be plotted at the very top and bottom of the chart.

errorfg

The color to display the current quote at the top of the graph if the stock server is having trouble retrieving a stock quote.

livedata

The URL to use to fetch data from a live source.

staticdata

The URL to use to fetch data from a static file.

fudge

A boolean controlling whether or not the server should fudge new quotes if it is unable to read real quotes from the stock feed (used to show dynamic data in demo situations - deprecated).

Closed Caption applet parameters

Example:

<applet codebase=classes code=ClosedCaption.class width=320 height=112>
    <param name=lines value=8>
    <param name=channel value=KPIX>
    <param name=data value="static:captiondata">
</applet>

data

The URL to fetch the closed caption text from. The data is simply read as lines of ascii text. The URL can point at a static file of ascii text, or it could point to an HTTP script which continuously monitored the closed captioning channel of a live broadcast and downloaded the resulting text over the connection, leaving it open until the applet closes the connection.

channel

The call letters of the station to be monitored.

lines

The number of lines of caption text to be displayed and buffered.

Stock Applet Data Formats

Stock Ticker and Quote History Chart applet data format

Example (for SUNW):

	@SUNW 0 99.75
	^SUNW 100
	_SUNW 93.125
	<SUNW 93.25
	#SUNW
	SUNW 99.75

The lines above are all of the same format. Each line consists of 3 or 4 items:

'@'{stock symbol} {timestamp} {floating point quote}

The '@' character indicates a historical quote. If the timestamp is 0 or less, then it is the number of seconds prior to the current time when the quote was valid. This relative format lets a static file contain information which always appears "new", even though it is a snapshot of past data. Live quote servers should always use absolute positive timestamps representing the number of seconds since 00:00:00 GMT on January 1, 1970.

'^'{stock symbol} {floating point quote}

The '^' character indicates a localized "high" quote, or the highest value the stock was traded at in the past day of trading.

'_'{stock symbol} {floating point quote}

The '_' character indicates a localized "low" quote, or the lowest value the stock was traded at in the past day of trading.

'<'{stock symbol} {floating point quote}

The '<' character indicates the previous trading day's closing price for this stock.

'#'{stock symbol}

The '#' character indicates that quotes for the stock are temporarily or permanently unavailable due to technical difficulties with the stock data feed.

{stock symbol} {floating point quote}

If none of the above prefix characters appears as the first character of the line, then the line is the latest stock price available to the stock feed server.

Closed Caption applet data format

The Closed Caption applet reads a simple ascii file. The file can either be a static file or it could be a dynamic file generated by a server reading live closed caption text from a television broadcast and sending the information down through some sort of network connection to the applet.

Questions?