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I/O classes
I/O classes.
Package Specification
Classes in this package fulfill needs that are not satisfied by the
I/O classes available.
Reading text
We provide replacement classes such as {@link it.unimi.dsi.io.FastBufferedReader}
and classes exposing the lines of a file as a {@linkplain it.unimi.dsi.io.FileLinesCollection collection}
or as an {@linkplain it.unimi.dsi.io.LineIterator iterator}. The general
{@link it.unimi.dsi.io.WordReader} interface is used by
MG4J to provide customisable word segmentation.
Bit-level I/O
The standard Java API lacks bit-level I/O classes: to this purpose, we
provide {@link it.unimi.dsi.io.InputBitStream} and {@link
it.unimi.dsi.io.OutputBitStream}, which can wrap any standard Java
corresponding stream and make it work at the bit level; moreover, they
provide support for several useful formats (such as unary, binary, minimal
binary, γ, δ and Golomb encoding).
Bit input and output streams offer also efficient buffering and a way to
reposition the bit stream in case the underlying byte stream is a
file-based stream or a {@link it.unimi.dsi.fastutil.io.RepositionableStream}.
Conventions
All coding methods work on natural numbers. The
encoding of zero is very natural for some techniques, and much less natural
for others. To keep methods rationally organised, all methods are able to
encode any natural number. If, for instance, you want to write positive
numbers in unary encoding and you do not want to waste a bit, you have to
decrement them first (i.e., instead of p you must encode
p−1).