fr.umlv.tatoo.runtime.buffer.impl
Class ReadableByteChannelWrapper

java.lang.Object
  fr.umlv.tatoo.runtime.buffer.impl.AbstractBufferWrapper
      fr.umlv.tatoo.runtime.buffer.impl.ReadableByteChannelWrapper

All Implemented Interfaces:

LexerBuffer, TokenBuffer<ByteBuffer>

public class ReadableByteChannelWrapper
extends AbstractBufferWrapper
implements TokenBuffer<ByteBuffer>, LexerBuffer

A ReadableByteChannelWrapper wraps a ReadableByteChannel in order to allow a lexer to process its content in order to have its tokens extracted.

Author:

Julien

See Also:

Lexer

Constructor Summary

ReadableByteChannelWrapper(boolean direct, int capacity, int increment, int chunkSize, ReadableByteChannel readable, LocationTracker tracker)
Construct a ReadableByteChannelWrapper used by the lexer to process the ReadableByteChannel.

ReadableByteChannelWrapper(ReadableByteChannel readable, LocationTracker tracker)
Constructs a ReadableByteChannelWrapper with default behavior.

Method Summary

protected void	discardImpl()
ReadableByteChannel	getReadableByteChannel()
boolean	hasRemaining() Returns true if more characters are availables in the buffer.
int	lastChar() Returns last read char or -1 if not available.
protected int	nextImpl() Returns next character in buffer without taking care of locations
boolean	previousWasNewLine() Determines if the last unwinded character was an end of line.
boolean	read() Reads at some bytes from the stream.
protected void	resetImpl() Moves current position back to first non unwinded character without taking care of locations
void	restart(ReadableByteChannel readableByteChannel)
protected void	restartImpl()
String	toString() Returns a String representation of the current token using the platform default encoding.
String	toString(String encoding) Returns a String representation of the current token using the specified encoding.
protected void	unwindImpl(int l) Performs unwind operation on buffer without taking care of locations
ByteBuffer	view() Returns the token part of the buffer as a ByteBuffer.

Methods inherited from class fr.umlv.tatoo.runtime.buffer.impl.AbstractBufferWrapper

discard, getLocationProvider, locationClear, next, reset, restart, unwind

Methods inherited from class java.lang.Object

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

Methods inherited from interface fr.umlv.tatoo.runtime.buffer.TokenBuffer

discard

Methods inherited from interface fr.umlv.tatoo.runtime.buffer.LexerBuffer

discard, getLocationProvider, next, reset, restart, unwind

Constructor Detail

ReadableByteChannelWrapper

public ReadableByteChannelWrapper(ReadableByteChannel readable,
                                  LocationTracker tracker)

Constructs a ReadableByteChannelWrapper with default behavior.

Parameters:

readable - the readable to wrap

ReadableByteChannelWrapper

public ReadableByteChannelWrapper(boolean direct,
                                  int capacity,
                                  int increment,
                                  int chunkSize,
                                  ReadableByteChannel readable,
                                  LocationTracker tracker)

Construct a ReadableByteChannelWrapper used by the lexer to process the ReadableByteChannel. The parameters specify how the underlying buffer which stores data in allocated and reallocated when more space is needed.

Parameters:

direct - if the ByteBuffer must be direct

capacity - the initial capacity

increment - how much to increment the size of the buffer when more space is required

chunkSize - how many bytes are read at once is the input

readable - the input

tracker - the location tracker

Method Detail

resetImpl

protected void resetImpl()

Description copied from class: AbstractBufferWrapper

Moves current position back to first non unwinded character without taking care of locations

Specified by:

resetImpl in class AbstractBufferWrapper

See Also:

LexerBuffer.reset()

unwindImpl

protected void unwindImpl(int l)

Description copied from class: AbstractBufferWrapper

Performs unwind operation on buffer without taking care of locations

Specified by:

unwindImpl in class AbstractBufferWrapper

Parameters:

l - the number of characters to unwind

See Also:

LexerBuffer.unwind(int)

previousWasNewLine

public boolean previousWasNewLine()

Description copied from interface: LexerBuffer

Determines if the last unwinded character was an end of line.

Specified by:

previousWasNewLine in interface LexerBuffer

Returns:

true if the last unwinded character was an end of line; false otherwise

hasRemaining

public boolean hasRemaining()

Description copied from interface: LexerBuffer

Returns true if more characters are availables in the buffer. If the end of file has been reached and backtracked by lexer this method must return true.

Specified by:

hasRemaining in interface LexerBuffer

Returns:

true if more characters are availables in the buffer

read

public boolean read()
             throws IOException

Description copied from interface: LexerBuffer

Reads at some bytes from the stream. This operation is optionnal and only used by SimpleLexer.run().

Specified by:

read in interface LexerBuffer

Returns:

false at end of stream

Throws:

IOException - if an i/o operation failed.

nextImpl

protected int nextImpl()

Description copied from class: AbstractBufferWrapper

Returns next character in buffer without taking care of locations

Specified by:

nextImpl in class AbstractBufferWrapper

Returns:

the next character in the buffer

See Also:

LexerBuffer.next()

restart

public void restart(ReadableByteChannel readableByteChannel)

getReadableByteChannel

public ReadableByteChannel getReadableByteChannel()

discardImpl

protected void discardImpl()

Specified by:

discardImpl in class AbstractBufferWrapper

toString

public String toString()

Returns a String representation of the current token using the platform default encoding. This method must only be used for debug since it is not efficient since it recreates the CharsetDecoder at each call.

Overrides:

toString in class Object

Returns:

a String representation of the current token

See Also:

Charset.defaultCharset()

toString

public String toString(String encoding)

Returns a String representation of the current token using the specified encoding. This method must only be used for debug since it is not efficient since it recreates the CharsetDecoder at each call.

Parameters:

encoding - the character encoding

Returns:

a String representation of the current token

See Also:

Charset

restartImpl

protected void restartImpl()

Specified by:

restartImpl in class AbstractBufferWrapper

view

public ByteBuffer view()

Returns the token part of the buffer as a ByteBuffer. The Buffer.limit() index must not be moved, the Buffer.position() can be moved, but any data before it can be discarded by the wrapper.

Specified by:

view in interface TokenBuffer<ByteBuffer>

Returns:

the token part of the buffer as a ByteBuffer

lastChar

public int lastChar()

Description copied from interface: LexerBuffer

Returns last read char or -1 if not available. This method is used for logging and error reporting. This operation is optional since this method can return -1 anytime

Specified by:

lastChar in interface LexerBuffer

Returns:

last read char or -1 if not available