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

java.lang.Object
  extended by fr.umlv.tatoo.runtime.buffer.impl.AbstractBufferWrapper
      extended by fr.umlv.tatoo.runtime.buffer.impl.ReaderWrapper
All Implemented Interfaces:
LexerBuffer, TokenBuffer<CharSequence>, CharSequence

public class ReaderWrapper
extends AbstractBufferWrapper
implements TokenBuffer<CharSequence>, CharSequence

A ReaderWrapper wraps a Reader in order to allow a lexer to process its content in order to have its tokens extracted.

Author:
Julien
See Also:
Lexer

Constructor Summary
ReaderWrapper(int capacity, int increment, int chunkSize, Reader reader, LocationTracker tracker)
          Construct a ReaderWrapper used by the lexer to process the Reader.
ReaderWrapper(Reader reader, LocationTracker tracker)
          Constructs a ReaderWrapper with default behavior.
 
Method Summary
 char charAt(int index)
           
 void discardImpl()
           
 boolean hasRemaining()
          Returns true if more characters are availables in the buffer.
 int lastChar()
          Returns last read char or -1 if not available.
 int length()
           
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
protected  void restartImpl()
           
 CharSequence subSequence(int start, int end)
           
 String toString()
          Returns a String representation of the current token
protected  void unwindImpl(int l)
          Performs unwind operation on buffer without taking care of locations
 CharSequence view()
          Provides a view of all available tokens.
 
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
 

Constructor Detail

ReaderWrapper

public ReaderWrapper(Reader reader,
                     LocationTracker tracker)
Constructs a ReaderWrapper with default behavior.

Parameters:
reader - the Reader to wrap
tracker - the location tracker

ReaderWrapper

public ReaderWrapper(int capacity,
                     int increment,
                     int chunkSize,
                     Reader reader,
                     LocationTracker tracker)
Construct a ReaderWrapper used by the lexer to process the Reader. The parameters specify how the underlying buffer which stores data in allocated and reallocated when more space is needed.

Parameters:
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
reader - the input
Method Detail

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)

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()

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()

discardImpl

public void discardImpl()
Specified by:
discardImpl in class AbstractBufferWrapper

view

public CharSequence view()
Description copied from interface: TokenBuffer
Provides a view of all available tokens. Tokens are not copied from the buffer and thus may change during lexer process.

Specified by:
view in interface TokenBuffer<CharSequence>
Returns:
a view of all available tokens

length

public int length()
Specified by:
length in interface CharSequence

charAt

public char charAt(int index)
Specified by:
charAt in interface CharSequence

subSequence

public CharSequence subSequence(int start,
                                int end)
Specified by:
subSequence in interface CharSequence

toString

public String toString()
Returns a String representation of the current token

Specified by:
toString in interface CharSequence
Overrides:
toString in class Object
Returns:
a String representation of the current token

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

restartImpl

protected void restartImpl()
Specified by:
restartImpl in class AbstractBufferWrapper