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Working with Streams 595

17

problem, streams provide “buffering.” When buffering is used, data is written into the

stream, but is not written back out to the disk immediately. Instead, the stream’s buffer

fills and fills, and when it is full, it writes to the disk all at once.

FIGURE17.1 Encapsulation through streams.

Stream Monitor

Keyboard

Disk Disk

data

data

data

data

Although data is technically a plural noun, we treat it as singular, as do

nearly all native speakers of English.

NOTE

Picture water trickling into the top of a tank and the tank filling and filling, but no water

running out of the bottom. Figure 17.2 illustrates this idea.

FIGURE17.2
Filling the buffer.