com.github.javaparser

Class AbstractCharStream

java.lang.Object

com.github.javaparser.AbstractCharStream

All Implemented Interfaces:

CharStream

Direct Known Subclasses:

SimpleCharStream

public abstract class AbstractCharStream
extends Object
implements CharStream

An implementation of interface CharStream, where the stream is assumed to contain only ASCII characters (without unicode processing).

Field Summary

Fields

Modifier and Type	Field and Description
protected int	available
protected int[]	bufcolumn
protected char[]	buffer
protected int[]	bufline
protected int	bufpos Position in buffer.
protected int	bufsize
protected int	column
static int	DEFAULT_BUF_SIZE
protected int	inBuf
protected int	line
protected int	maxNextCharInd
protected char[]	nextCharBuf
protected int	nextCharInd
protected boolean	prevCharIsCR
protected boolean	prevCharIsLF
protected int	tokenBegin

Constructor Summary

Constructors

Constructor and Description
AbstractCharStream(int startline, int startcolumn, int buffersize) Constructor.

Method Summary

Modifier and Type	Method and Description
void	adjustBeginLineColumn(int nNewLine, int newCol) Method to adjust line and column numbers for the start of a token.
void	backup(int amount) Backs up the input stream by amount steps.
char	beginToken()
void	done() The lexer calls this function to indicate that it is done with the stream and hence implementations can free any resources held by this class.
protected void	expandBuff(boolean wrapAround)
protected void	fillBuff()
int	getBeginColumn()
int	getBeginLine()
int	getEndColumn()
int	getEndLine()
String	getImage()
char[]	getSuffix(int len)
int	getTabSize()
boolean	isTrackLineColumn()
char	readChar() Read a character.
void	reInit(int startline, int startcolumn, int buffersize) Reinitialise.
void	setTabSize(int i) Set the tab size to use.
void	setTrackLineColumn(boolean tlc) Enable or disable line number and column number tracking.
protected abstract void	streamClose()
protected abstract int	streamRead(char[] buf, int offset, int len)
protected void	updateLineColumn(char c)

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_BUF_SIZE

public static final int DEFAULT_BUF_SIZE

See Also:

Constant Field Values

bufpos

protected int bufpos

Position in buffer.

bufsize

protected int bufsize

available

protected int available

tokenBegin

protected int tokenBegin

bufline

protected int[] bufline

bufcolumn

protected int[] bufcolumn

column

protected int column

line

protected int line

prevCharIsCR

protected boolean prevCharIsCR

prevCharIsLF

protected boolean prevCharIsLF

buffer

protected char[] buffer

maxNextCharInd

protected int maxNextCharInd

inBuf

protected int inBuf

nextCharBuf

protected char[] nextCharBuf

nextCharInd

protected int nextCharInd

Constructor Detail

AbstractCharStream

public AbstractCharStream(int startline,
                          int startcolumn,
                          int buffersize)

Constructor.

Method Detail

setTabSize

public void setTabSize(int i)

Description copied from interface: CharStream

Set the tab size to use.

Specified by:

setTabSize in interface CharStream

Parameters:

i - spaces per tab

getTabSize

public int getTabSize()

Specified by:

getTabSize in interface CharStream

Returns:

Current tab size.

expandBuff

protected void expandBuff(boolean wrapAround)

streamRead

protected abstract int streamRead(char[] buf,
                                  int offset,
                                  int len)
                           throws IOException

Throws:

IOException

streamClose

protected abstract void streamClose()
                             throws IOException

Throws:

IOException

fillBuff

protected void fillBuff()
                 throws IOException

Throws:

IOException

beginToken

public char beginToken()
                throws IOException

Specified by:

beginToken in interface CharStream

Returns:

the next character that marks the beginning of the next token. All characters must remain in the buffer between two successive calls to this method to implement backup correctly.

Throws:

IOException

updateLineColumn

protected void updateLineColumn(char c)

readChar

public char readChar()
              throws IOException

Read a character.

Specified by:

readChar in interface CharStream

Returns:

the next character from the selected input

Throws:

IOException - on IO error

getBeginColumn

public int getBeginColumn()

Specified by:

getBeginColumn in interface CharStream

Returns:

the column number of the first character for current token (being matched after the last call to beginToken).

getBeginLine

public int getBeginLine()

Specified by:

getBeginLine in interface CharStream

Returns:

the line number of the first character for current token (being matched after the last call to BeginToken).

getEndColumn

public int getEndColumn()

Specified by:

getEndColumn in interface CharStream

Returns:

the column number of the last character for current token (being matched after the last call to BeginToken).

getEndLine

public int getEndLine()

Specified by:

getEndLine in interface CharStream

Returns:

the line number of the last character for current token (being matched after the last call to BeginToken).

backup

public void backup(int amount)

Description copied from interface: CharStream

Backs up the input stream by amount steps. Lexer calls this method if it had already read some characters, but could not use them to match a (longer) token. So, they will be used again as the prefix of the next token and it is the implemetation's responsibility to do this right.

Specified by:

backup in interface CharStream

Parameters:

amount - Number of chars to back up.

reInit

public void reInit(int startline,
                   int startcolumn,
                   int buffersize)

Reinitialise.

getImage

public String getImage()

Specified by:

getImage in interface CharStream

Returns:

a string made up of characters from the marked token beginning to the current buffer position. Implementations have the choice of returning anything that they want to. For example, for efficiency, one might decide to just return null, which is a valid implementation.

getSuffix

public char[] getSuffix(int len)

Specified by:

getSuffix in interface CharStream

Returns:

an array of characters that make up the suffix of length 'len' for the currently matched token. This is used to build up the matched string for use in actions in the case of MORE. A simple and inefficient implementation of this is as follows:

   {
      String t = getImage();
      return t.substring(t.length() - len, t.length()).toCharArray();
   }
 

done

public void done()

Description copied from interface: CharStream

The lexer calls this function to indicate that it is done with the stream and hence implementations can free any resources held by this class. Again, the body of this function can be just empty and it will not affect the lexer's operation.

Specified by:

done in interface CharStream

adjustBeginLineColumn

public void adjustBeginLineColumn(int nNewLine,
                                  int newCol)

Method to adjust line and column numbers for the start of a token.

setTrackLineColumn

public void setTrackLineColumn(boolean tlc)

Description copied from interface: CharStream

Enable or disable line number and column number tracking.

Specified by:

setTrackLineColumn in interface CharStream

Parameters:

tlc - true to track it, false to not do it.

isTrackLineColumn

public boolean isTrackLineColumn()

Specified by:

isTrackLineColumn in interface CharStream

Returns:

true if line number and column numbers should be tracked.