org.jwat.common

Class ByteCountingPushBackInputStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

java.io.PushbackInputStream

org.jwat.common.ByteCountingPushBackInputStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class ByteCountingPushBackInputStream
extends java.io.PushbackInputStream

Basic PushBackInputStream that also keeps track of the number of consumed bytes at any given time.

Author:

nicl

Field Summary

Fields

Modifier and Type	Field and Description
protected long	consumed Offset relative to beginning of stream.
protected long	counter Byte counter which can also be changed.
protected int	pushback_size Pushback buffer size.
static int	READLINE_INITIAL_SIZE Read line initial size.

Fields inherited from class java.io.PushbackInputStream

buf, pos

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

Constructors

Constructor and Description
ByteCountingPushBackInputStream(java.io.InputStream in, int size) Given an InputStream and a push back buffer size returns a wrapped input stream with push back capabilities.

Method Summary

Modifier and Type	Method and Description
long	getConsumed() Retrieve the number of bytes consumed by this stream.
long	getCounter() Retrieve the current counter value.
int	getPushbackSize() Get the pushback buffer size.
void	mark(int readlimit)
boolean	markSupported()
int	peek(byte[] buffer) Peek into the stream by filling as much of the supplied array as possible before unreading the stream and returning.
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)
int	readFully(byte[] buffer) Guaranteed to read the exact number of bytes that are in the array, if not, the bytes are pushed back into the stream before returning.
java.lang.String	readLine() Read a single line into a string.
void	reset()
void	setCounter(long bytes) Change the counter value.
long	skip(long n)
void	unread(byte[] b)
void	unread(byte[] b, int off, int len)
void	unread(int b)

Methods inherited from class java.io.PushbackInputStream

available, close

Methods inherited from class java.lang.Object

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

Field Detail

READLINE_INITIAL_SIZE

public static final int READLINE_INITIAL_SIZE

Read line initial size.

See Also:

Constant Field Values

pushback_size

protected int pushback_size

Pushback buffer size.

consumed

protected long consumed

Offset relative to beginning of stream.

counter

protected long counter

Byte counter which can also be changed.

Constructor Detail

ByteCountingPushBackInputStream

public ByteCountingPushBackInputStream(java.io.InputStream in,
                                       int size)

Given an InputStream and a push back buffer size returns a wrapped input stream with push back capabilities.

Parameters:

in - InputStream to wrap

size - push back buffer size

Method Detail

getPushbackSize

public int getPushbackSize()

Get the pushback buffer size.

Returns:

pushback buffer size

getConsumed

public long getConsumed()

Retrieve the number of bytes consumed by this stream.

Returns:

current byte offset in this stream

setCounter

public void setCounter(long bytes)

Change the counter value. Useful for reading zero indexed relative data.

Parameters:

bytes - new counter value

getCounter

public long getCounter()

Retrieve the current counter value.

Returns:

current counter value

markSupported

public boolean markSupported()

Overrides:

markSupported in class java.io.PushbackInputStream

mark

public void mark(int readlimit)

Overrides:

mark in class java.io.PushbackInputStream

reset

public void reset()
           throws java.io.IOException

Overrides:

reset in class java.io.PushbackInputStream

Throws:

java.io.IOException

read

public int read()
         throws java.io.IOException

Overrides:

read in class java.io.PushbackInputStream

Throws:

java.io.IOException

read

public int read(byte[] b)
         throws java.io.IOException

Overrides:

read in class java.io.FilterInputStream

Throws:

java.io.IOException

read

public int read(byte[] b,
                int off,
                int len)
         throws java.io.IOException

Overrides:

read in class java.io.PushbackInputStream

Throws:

java.io.IOException

skip

public long skip(long n)
          throws java.io.IOException

Overrides:

skip in class java.io.PushbackInputStream

Throws:

java.io.IOException

unread

public void unread(int b)
            throws java.io.IOException

Overrides:

unread in class java.io.PushbackInputStream

Throws:

java.io.IOException

unread

public void unread(byte[] b)
            throws java.io.IOException

Overrides:

unread in class java.io.PushbackInputStream

Throws:

java.io.IOException

unread

public void unread(byte[] b,
                   int off,
                   int len)
            throws java.io.IOException

Overrides:

unread in class java.io.PushbackInputStream

Throws:

java.io.IOException

readLine

public java.lang.String readLine()
                          throws java.io.IOException

Read a single line into a string.

Returns:

single string line

Throws:

java.io.IOException - if an I/O error occurs while reading line

readFully

public int readFully(byte[] buffer)
              throws java.io.IOException

Guaranteed to read the exact number of bytes that are in the array, if not, the bytes are pushed back into the stream before returning.

Parameters:

buffer - byte buffer to read bytes into

Returns:

the number of bytes read into array

Throws:

java.io.IOException - if an I/O error occurs while reading array

peek

public int peek(byte[] buffer)
         throws java.io.IOException

Peek into the stream by filling as much of the supplied array as possible before unreading the stream and returning.

Parameters:

buffer - byte buffer to read bytes into

Returns:

the number of bytes read into array

Throws:

java.io.IOException - if an I/O error occurs while reading array