it.unimi.dsi.io
Class DebugInputBitStream

java.lang.Object
  it.unimi.dsi.fastutil.booleans.AbstractBooleanIterator
      it.unimi.dsi.io.InputBitStream
          it.unimi.dsi.io.DebugInputBitStream

All Implemented Interfaces:

BooleanIterator, Closeable, Flushable, Iterator<Boolean>

public class DebugInputBitStream
extends InputBitStream

A debugging wrapper for input bit streams.

This class can be used to wrap an input bit stream. The semantics of the resulting read operations is unchanged, but each operation will be logged. The conventions are the same as those of DebugOutputBitStream, with the following additions:

!

reset();

+>

skip().

Since:

1.1

Author:

Sebastiano Vigna

Field Summary

Fields inherited from class it.unimi.dsi.io.InputBitStream

avail, buffer, DEFAULT_BUFFER_SIZE, DELTA, fileChannel, fill, GAMMA, is, pos, position, repositionableStream, SHIFTED_GAMMA, wrapping, ZETA_3

Constructor Summary

DebugInputBitStream(InputBitStream ibs)
Creates a new debug input bit stream wrapping a given input bit stream and logging on standard error.

DebugInputBitStream(InputBitStream ibs, PrintStream pw)
Creates a new debug input bit stream wrapping a given input bit stream and logging on a given writer.

Method Summary

void	align() Aligns the stream.
long	available() Returns the number of bits that can be read (or skipped over) from this bit stream without blocking by the next caller of a method.
void	close() Closes the bit stream.
void	flush() Flushes the bit stream.
void	position(long position) Sets this stream bit position, if it is based on a RepositionableStream or on a FileChannel.
void	read(byte[] bits, int len) Reads a sequence of bits.
int	readBit() Reads a bit.
long	readBits() Returns the number of bits read from this bit stream.
void	readBits(long readBits) Sets the number of bits read from this bit stream.
int	readDelta() Reads a natural number in δ coding.
int	readGamma() Reads a natural number in γ coding.
int	readGolomb(int b) Reads a natural number in Golomb coding.
int	readGolomb(int b, int log2b) Reads a natural number in Golomb coding.
int	readInt(int len) Reads a fixed number of bits into an integer.
long	readLong(int len) Reads a fixed number of bits into a long.
long	readLongDelta() Reads a long natural number in δ coding.
long	readLongGamma() Reads a long natural number in γ coding.
long	readLongGolomb(long b) Reads a long natural number in Golomb coding.
long	readLongGolomb(long b, int log2b) Reads a long natural number in Golomb coding.
long	readLongMinimalBinary(long b) Reads a long natural number in a limited range using a minimal binary coding.
long	readLongMinimalBinary(long b, int log2b) Reads a long natural number in a limited range using a minimal binary coding.
long	readLongNibble() Reads a long natural number in variable-length nibble coding.
long	readLongSkewedGolomb(long b) Reads a long natural number in skewed Golomb coding.
long	readLongUnary() Reads a long natural number in unary coding.
long	readLongZeta(int k) Reads a long natural number in ζ coding.
int	readMinimalBinary(int b) Reads a natural number in a limited range using a minimal binary coding.
int	readMinimalBinary(int b, int log2b) Reads a natural number in a limited range using a minimal binary coding.
int	readNibble() Reads a natural number in variable-length nibble coding.
int	readSkewedGolomb(int b) Reads a natural number in skewed Golomb coding.
int	readUnary() Reads a natural number in unary coding.
int	readZeta(int k) Reads a natural number in ζ coding.
void	reset() Repositions this bit stream to the position at the time the InputBitStream.mark(int) method was last called.
int	skip(int n) Deprecated.
long	skip(long n) Skips the given number of bits.

Methods inherited from class it.unimi.dsi.io.InputBitStream

hasNext, mark, markSupported, nextBoolean, readDeltas, readGammas, readLongShiftedGamma, readShiftedGamma, readShiftedGammas, readZetas, skipDeltas, skipDeltas, skipGammas, skipGammas, skipShiftedGammas, skipShiftedGammas, skipZetas, skipZetas

Methods inherited from class it.unimi.dsi.fastutil.booleans.AbstractBooleanIterator

next, remove

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DebugInputBitStream

public DebugInputBitStream(InputBitStream ibs,
                           PrintStream pw)

Creates a new debug input bit stream wrapping a given input bit stream and logging on a given writer.

Parameters:

ibs - the input bit stream to wrap.

pw - a print stream that will receive the logging data.

DebugInputBitStream

public DebugInputBitStream(InputBitStream ibs)

Creates a new debug input bit stream wrapping a given input bit stream and logging on standard error.

Parameters:

ibs - the input bit stream to wrap.

Method Detail

align

public void align()

Description copied from class: InputBitStream

Aligns the stream. After a call to this function, the stream is byte aligned. Bits that have been read to align are discarded.

Overrides:

align in class InputBitStream

available

public long available()
               throws IOException

Description copied from class: InputBitStream

Returns the number of bits that can be read (or skipped over) from this bit stream without blocking by the next caller of a method.

Overrides:

available in class InputBitStream

Returns:

the number of bits that can be read from this bit stream without blocking.

Throws:

IOException

close

public void close()
           throws IOException

Description copied from class: InputBitStream

Closes the bit stream. All resources associated with the stream are released.

Specified by:

close in interface Closeable

Overrides:

close in class InputBitStream

Throws:

IOException

flush

public void flush()

Description copied from class: InputBitStream

Flushes the bit stream. All state information associated with the stream is reset. This includes bytes prefetched from the stream, bits in the bit buffer and unget'd bits.

This method is provided so that users of this class can easily wrap repositionable streams (for instance, file-based streams, which can be repositioned using the underlying FileChannel). It is guaranteed that after calling this method the underlying stream can be repositioned, and that the next read will draw data from the stream.

Specified by:

flush in interface Flushable

Overrides:

flush in class InputBitStream

position

public void position(long position)
              throws IOException

Description copied from class: InputBitStream

Sets this stream bit position, if it is based on a RepositionableStream or on a FileChannel.

Given an underlying stream that implements RepositionableStream or that can provide a FileChannel via the getChannel() method, a call to this method has the same semantics of a InputBitStream.flush(), followed by a call to position(position / 8) on the byte stream, followed by a skip(position % 8).

Note that this method does not change the value returned by InputBitStream.readBits().

Overrides:

position in class InputBitStream

Parameters:

position - the new position expressed as a bit offset.

Throws:

IOException

See Also:

FileChannel.position(long)

read

public void read(byte[] bits,
                 int len)
          throws IOException

Description copied from class: InputBitStream

Reads a sequence of bits. Bits will be read in the natural way: the first bit is bit 7 of the first byte, the eightth bit is bit 0 of the first byte, the ninth bit is bit 7 of the second byte and so on.

Overrides:

read in class InputBitStream

Parameters:

bits - an array of bytes to store the result.

len - the number of bits to read.

Throws:

IOException

readBit

public int readBit()
            throws IOException

Description copied from class: InputBitStream

Reads a bit.

Overrides:

readBit in class InputBitStream

Returns:

the next bit from the stream.

Throws:

IOException

readBits

public long readBits()

Description copied from class: InputBitStream

Returns the number of bits read from this bit stream.

Overrides:

readBits in class InputBitStream

Returns:

the number of bits read so far.

readBits

public void readBits(long readBits)

Description copied from class: InputBitStream

Sets the number of bits read from this bit stream.

This method is provided so that, for instance, the user can reset via readBits(0) the read-bits count after a InputBitStream.flush().

Overrides:

readBits in class InputBitStream

Parameters:

readBits - the new value for the number of bits read so far.

readDelta

public int readDelta()
              throws IOException

Description copied from class: InputBitStream

Reads a natural number in δ coding.

Overrides:

readDelta in class InputBitStream

Returns:

the next δ-encoded natural number.

Throws:

IOException

See Also:

OutputBitStream.writeDelta(int), InputBitStream.skipDeltas(int)

readGamma

public int readGamma()
              throws IOException

Description copied from class: InputBitStream

Reads a natural number in γ coding.

Overrides:

readGamma in class InputBitStream

Returns:

the next γ-encoded natural number.

Throws:

IOException

See Also:

OutputBitStream.writeGamma(int), InputBitStream.skipGammas(int)

readGolomb

public int readGolomb(int b,
                      int log2b)
               throws IOException

Description copied from class: InputBitStream

Reads a natural number in Golomb coding. This method is faster than InputBitStream.readGolomb(int) because it does not have to compute log2b.

This method implements also the case in which b is 0: in this case, nothing will be read, and 0 will be returned.

Overrides:

readGolomb in class InputBitStream

Parameters:

b - the modulus for the coding.

log2b - the floor of the base-2 logarithm of the coding modulus.

Returns:

the next Golomb-encoded natural number.

Throws:

IOException

See Also:

OutputBitStream.writeGolomb(int, int)

readGolomb

public int readGolomb(int b)
               throws IOException

Description copied from class: InputBitStream

Reads a natural number in Golomb coding.

This method implements also the case in which b is 0: in this case, nothing will be read, and 0 will be returned.

Overrides:

readGolomb in class InputBitStream

Parameters:

b - the modulus for the coding.

Returns:

the next Golomb-encoded natural number.

Throws:

IOException

See Also:

OutputBitStream.writeGolomb(int, int)

readInt

public int readInt(int len)
            throws IOException

Description copied from class: InputBitStream

Reads a fixed number of bits into an integer.

Overrides:

readInt in class InputBitStream

Parameters:

len - a bit length.

Returns:

an integer whose lower len bits are taken from the stream; the rest is zeroed.

Throws:

IOException

readLong

public long readLong(int len)
              throws IOException

Description copied from class: InputBitStream

Reads a fixed number of bits into a long.

Overrides:

readLong in class InputBitStream

Parameters:

len - a bit length.

Returns:

a long whose lower len bits are taken from the stream; the rest is zeroed.

Throws:

IOException

readLongDelta

public long readLongDelta()
                   throws IOException

Description copied from class: InputBitStream

Reads a long natural number in δ coding.

Overrides:

readLongDelta in class InputBitStream

Returns:

the next δ-encoded long natural number.

Throws:

IOException

See Also:

OutputBitStream.writeDelta(int), InputBitStream.skipDeltas(int)

readLongGamma

public long readLongGamma()
                   throws IOException

Description copied from class: InputBitStream

Reads a long natural number in γ coding.

Overrides:

readLongGamma in class InputBitStream

Returns:

the next γ-encoded long natural number.

Throws:

IOException

See Also:

OutputBitStream.writeGamma(int), InputBitStream.skipGammas(int)

readLongGolomb

public long readLongGolomb(long b,
                           int log2b)
                    throws IOException

Description copied from class: InputBitStream

Reads a long natural number in Golomb coding. This method is faster than InputBitStream.readLongGolomb(long) because it does not have to compute log2b.

This method implements also the case in which b is 0: in this case, nothing will be read, and 0 will be returned.

Overrides:

readLongGolomb in class InputBitStream

Parameters:

b - the modulus for the coding.

log2b - the floor of the base-2 logarithm of the coding modulus.

Returns:

the next Golomb-encoded long natural number.

Throws:

IOException

See Also:

OutputBitStream.writeGolomb(int, int)

readLongGolomb

public long readLongGolomb(long b)
                    throws IOException

Description copied from class: InputBitStream

Reads a long natural number in Golomb coding.

This method implements also the case in which b is 0: in this case, nothing will be read, and 0 will be returned.

Overrides:

readLongGolomb in class InputBitStream

Parameters:

b - the modulus for the coding.

Returns:

the next Golomb-encoded long natural number.

Throws:

IOException

See Also:

OutputBitStream.writeGolomb(int, int)

readLongMinimalBinary

public long readLongMinimalBinary(long b,
                                  int log2b)
                           throws IOException

Description copied from class: InputBitStream

Reads a long natural number in a limited range using a minimal binary coding. This method is faster than InputBitStream.readLongMinimalBinary(long) because it does not have to compute log2b.

Overrides:

readLongMinimalBinary in class InputBitStream

Parameters:

b - a strict upper bound.

log2b - the floor of the base-2 logarithm of the bound.

Returns:

the next minimally binary encoded long natural number.

Throws:

IOException

See Also:

OutputBitStream.writeMinimalBinary(int, int)

readLongMinimalBinary

public long readLongMinimalBinary(long b)
                           throws IOException

Description copied from class: InputBitStream

Reads a long natural number in a limited range using a minimal binary coding.

Overrides:

readLongMinimalBinary in class InputBitStream

Parameters:

b - a strict upper bound.

Returns:

the next minimally binary encoded long natural number.

Throws:

IOException

See Also:

OutputBitStream.writeMinimalBinary(int, int)

readLongNibble

public long readLongNibble()
                    throws IOException

Description copied from class: InputBitStream

Reads a long natural number in variable-length nibble coding.

Overrides:

readLongNibble in class InputBitStream

Returns:

the next variable-length nibble-encoded long natural number.

Throws:

IOException

See Also:

OutputBitStream.writeNibble(int)

readLongSkewedGolomb

public long readLongSkewedGolomb(long b)
                          throws IOException

Description copied from class: InputBitStream

Reads a long natural number in skewed Golomb coding.

This method implements also the case in which b is 0: in this case, nothing will be read, and 0 will be returned.

Overrides:

readLongSkewedGolomb in class InputBitStream

Parameters:

b - the modulus for the coding.

Returns:

the next skewed Golomb-encoded long natural number.

Throws:

IOException

See Also:

OutputBitStream.writeSkewedGolomb(int, int)

readLongUnary

public long readLongUnary()
                   throws IOException

Description copied from class: InputBitStream

Reads a long natural number in unary coding. Note that by unary coding we mean that 1 encodes 0, 01 encodes 1 and so on.

Overrides:

readLongUnary in class InputBitStream

Returns:

the next unary-encoded long natural number.

Throws:

IOException

See Also:

OutputBitStream.writeUnary(int)

readLongZeta

public long readLongZeta(int k)
                  throws IOException

Description copied from class: InputBitStream

Reads a long natural number in ζ coding.

Overrides:

readLongZeta in class InputBitStream

Parameters:

k - the shrinking factor.

Returns:

the next ζ-encoded long natural number.

Throws:

IOException

See Also:

OutputBitStream.writeZeta(int, int)

readMinimalBinary

public int readMinimalBinary(int b,
                             int log2b)
                      throws IOException

Description copied from class: InputBitStream

Reads a natural number in a limited range using a minimal binary coding. This method is faster than InputBitStream.readMinimalBinary(int) because it does not have to compute log2b.

Overrides:

readMinimalBinary in class InputBitStream

Parameters:

b - a strict upper bound.

log2b - the floor of the base-2 logarithm of the bound.

Returns:

the next minimally binary encoded natural number.

Throws:

IOException

See Also:

OutputBitStream.writeMinimalBinary(int, int)

readMinimalBinary

public int readMinimalBinary(int b)
                      throws IOException

Description copied from class: InputBitStream

Reads a natural number in a limited range using a minimal binary coding.

Overrides:

readMinimalBinary in class InputBitStream

Parameters:

b - a strict upper bound.

Returns:

the next minimally binary encoded natural number.

Throws:

IOException

See Also:

OutputBitStream.writeMinimalBinary(int, int)

readNibble

public int readNibble()
               throws IOException

Description copied from class: InputBitStream

Reads a natural number in variable-length nibble coding.

Overrides:

readNibble in class InputBitStream

Returns:

the next variable-length nibble-encoded natural number.

Throws:

IOException

See Also:

OutputBitStream.writeNibble(int)

readSkewedGolomb

public int readSkewedGolomb(int b)
                     throws IOException

Description copied from class: InputBitStream

Reads a natural number in skewed Golomb coding.

This method implements also the case in which b is 0: in this case, nothing will be read, and 0 will be returned.

Overrides:

readSkewedGolomb in class InputBitStream

Parameters:

b - the modulus for the coding.

Returns:

the next skewed Golomb-encoded natural number.

Throws:

IOException

See Also:

OutputBitStream.writeSkewedGolomb(int, int)

readUnary

public int readUnary()
              throws IOException

Description copied from class: InputBitStream

Reads a natural number in unary coding.

Overrides:

readUnary in class InputBitStream

Returns:

the next unary-encoded natural number.

Throws:

IOException

See Also:

OutputBitStream.writeUnary(int)

readZeta

public int readZeta(int k)
             throws IOException

Description copied from class: InputBitStream

Reads a natural number in ζ coding.

Overrides:

readZeta in class InputBitStream

Parameters:

k - the shrinking factor.

Returns:

the next ζ-encoded natural number.

Throws:

IOException

See Also:

OutputBitStream.writeZeta(int, int)

reset

public void reset()
           throws IOException

Description copied from class: InputBitStream

Repositions this bit stream to the position at the time the InputBitStream.mark(int) method was last called.

This method will just flush the stream and delegate the reset to the underlying InputStream.

Overrides:

reset in class InputBitStream

Throws:

IOException

skip

@Deprecated
public int skip(int n)

Deprecated.

Description copied from class: InputBitStream

Skips over the given number of bits.

Specified by:

skip in interface BooleanIterator

Overrides:

skip in class InputBitStream

Parameters:

n - the number of bits to skip.

Returns:

the number of bits actually skipped.

skip

public long skip(long n)
          throws IOException

Description copied from class: InputBitStream

Skips the given number of bits.

Overrides:

skip in class InputBitStream

Parameters:

n - the number of bits to skip.

Returns:

the actual number of skipped bits.

Throws:

IOException