Page 141 - DCAP408_WEB_PROGRAMMING

Unit 8: File I/O

Notes
Example: The demo keeps the list of initial states in a balanced tree. If desired the
list could be included with the meta data of the document or stored in some other fashion.
Care must be taken when looking at initial positions after start position. If text has been
added or removed from the document, the positions after the addition/removal will have
changed.

Only what is Visible

The initial coloring time for a document may become an issue. One way around this would be
to only color what is visible on the screen. If the user scrolls, then more of the document will
have to be colored as the user scrolls.
Another approach that is used by the demo is to start a separate thread to do the coloring. In this
case, the document coloring happens in the background and the user may modify the document
while that happens.

Self Assessment

Fill in the blanks:
8. The syntax lexers accept your document through Streams and …………………...
9. If the lexer returns to an initial state at the same point that it returned to an initial state the
last time, the rest of the document is already ……………….. correctly.
10. The internet is littered with hundreds of unfinished or poorly working …………………….



Caselet Television anywhere, anytime…

hat is the future of television? How is the structure of television programming
going to change? Will people be watching TV rather than Internet TV? How
Wwill TV-on-demand affect the industry?
Listing a series of such questions, Bill Roedy, the former head of MTV Networks
International, confesses that he does not know the answer to these common posers. He
hastens to caution that if anyone tells you they know, you should not believe them.
“Nobody knows for sure. The architecture of the business is changing and every media
company is grappling with it. This kind of earthquake can destroy great companies but it
also provides tremendous opportunities. There are huge shifts in the wind and the goal is
to catch that wind and go with it,” writes Roedy in ‘What Makes Business Rock: Building
the world’s largest global networks’ (www.wiley.com).
Delivery Systems have Changed

Looking back, the author notes that the basic concept behind all of the media world has
not changed – viz. the ability to send pictures and sound through the air so countless
people can see and hear them at precisely the same time. However, what has changed, and
is continuing to change, are the delivery systems, the way content is distributed and the
ability of a viewer to choose what and when they want to see, he adds.
Contd...

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