org.apache.derby.impl.sql.compile
Class UCode_CharStream

java.lang.Object
  org.apache.derby.impl.sql.compile.UCode_CharStream

All Implemented Interfaces:

CharStream

public final class UCode_CharStream
extends java.lang.Object
implements CharStream

An implementation of interface CharStream, where the stream is assumed to contain only Unicode characters.

Field Summary

(package private) int	available
private int[]	bufcolumn
private char[]	buffer
private int[]	bufline
int	bufpos
(package private) int	bufsize
(package private) int	charCnt
(package private) int[]	charOffset
private int	column
private int	inBuf
private java.io.Reader	inputStream
private int	line
private int	maxNextCharInd
private char[]	nextCharBuf
private int	nextCharInd
private boolean	prevCharIsCR
private boolean	prevCharIsLF
static boolean	staticFlag
(package private) int	tokenBegin

Constructor Summary

UCode_CharStream(java.io.InputStream dstream, int startline, int startcolumn)

UCode_CharStream(java.io.InputStream dstream, int startline, int startcolumn, int buffersize)

UCode_CharStream(java.io.Reader dstream, int startline, int startcolumn)

UCode_CharStream(java.io.Reader dstream, int startline, int startcolumn, int buffersize)

Method Summary

void	adjustBeginLineColumn(int newLine, 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() Returns the next character that marks the beginning of the next token.
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.
private void	ExpandBuff(boolean wrapAround)
private void	FillBuff()
int	getBeginColumn() Returns the column number of the first character for current token (being matched after the last call to BeginTOken).
int	getBeginLine() Returns the line number of the first character for current token (being matched after the last call to BeginTOken).
int	getBeginOffset()
int	getColumn() Deprecated.
int	getEndColumn() Returns the column number of the last character for current token (being matched after the last call to BeginTOken).
int	getEndLine() Returns the line number of the last character for current token (being matched after the last call to BeginTOken).
int	getEndOffset()
java.lang.String	GetImage() Returns a string made up of characters from the marked token beginning to the current buffer position.
int	getLine() Deprecated.
char[]	GetSuffix(int len) Returns an array of characters that make up the suffix of length 'len' for the currently matched token.
char	readChar() Returns the next character from the selected input.
private char	ReadChar()
void	ReInit(java.io.InputStream dstream, int startline, int startcolumn)
void	ReInit(java.io.InputStream dstream, int startline, int startcolumn, int buffersize)
void	ReInit(java.io.Reader dstream, int startline, int startcolumn)
void	ReInit(java.io.Reader dstream, int startline, int startcolumn, int buffersize)
private void	UpdateLineColumn(char c)

Methods inherited from class java.lang.Object

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

Field Detail

charCnt

int charCnt

charOffset

int[] charOffset

staticFlag

public static final boolean staticFlag

See Also:

Constant Field Values

bufpos

public int bufpos

bufsize

int bufsize

available

int available

tokenBegin

int tokenBegin

bufline

private int[] bufline

bufcolumn

private int[] bufcolumn

column

private int column

line

private int line

prevCharIsCR

private boolean prevCharIsCR

prevCharIsLF

private boolean prevCharIsLF

inputStream

private java.io.Reader inputStream

nextCharBuf

private char[] nextCharBuf

buffer

private char[] buffer

maxNextCharInd

private int maxNextCharInd

nextCharInd

private int nextCharInd

inBuf

private int inBuf

Constructor Detail

UCode_CharStream

public UCode_CharStream(java.io.Reader dstream,
                        int startline,
                        int startcolumn,
                        int buffersize)

UCode_CharStream

public UCode_CharStream(java.io.Reader dstream,
                        int startline,
                        int startcolumn)

UCode_CharStream

public UCode_CharStream(java.io.InputStream dstream,
                        int startline,
                        int startcolumn,
                        int buffersize)

UCode_CharStream

public UCode_CharStream(java.io.InputStream dstream,
                        int startline,
                        int startcolumn)

Method Detail

ExpandBuff

private final void ExpandBuff(boolean wrapAround)

FillBuff

private final void FillBuff()
                     throws java.io.IOException

Throws:

java.io.IOException

ReadChar

private final char ReadChar()
                     throws java.io.IOException

Throws:

java.io.IOException

BeginToken

public char BeginToken()
                throws java.io.IOException

Description copied from 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.

Specified by:

BeginToken in interface CharStream

Throws:

java.io.IOException

UpdateLineColumn

private final void UpdateLineColumn(char c)

readChar

public final char readChar()
                    throws java.io.IOException

Description copied from interface: CharStream

Returns the next character from the selected input. The method of selecting the input is the responsibility of the class implementing this interface. Can throw any java.io.IOException.

Specified by:

readChar in interface CharStream

Throws:

java.io.IOException

getColumn

public final int getColumn()

Deprecated.

Description copied from interface: CharStream

Returns the column position of the character last read.

Specified by:

getColumn in interface CharStream

See Also:

getEndColumn()

getLine

public final int getLine()

Deprecated.

Description copied from interface: CharStream

Returns the line number of the character last read.

Specified by:

getLine in interface CharStream

See Also:

getEndLine()

getEndColumn

public final int getEndColumn()

Description copied from interface: CharStream

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

Specified by:

getEndColumn in interface CharStream

getEndLine

public final int getEndLine()

Description copied from interface: CharStream

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

Specified by:

getEndLine in interface CharStream

getBeginColumn

public final int getBeginColumn()

Description copied from interface: CharStream

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

Specified by:

getBeginColumn in interface CharStream

getBeginLine

public final int getBeginLine()

Description copied from interface: CharStream

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

Specified by:

getBeginLine in interface CharStream

getBeginOffset

public final int getBeginOffset()

Specified by:

getBeginOffset in interface CharStream

getEndOffset

public final int getEndOffset()

Specified by:

getEndOffset in interface CharStream

backup

public final 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

ReInit

public void ReInit(java.io.Reader dstream,
                   int startline,
                   int startcolumn,
                   int buffersize)

Specified by:

ReInit in interface CharStream

ReInit

public void ReInit(java.io.Reader dstream,
                   int startline,
                   int startcolumn)

Specified by:

ReInit in interface CharStream

ReInit

public void ReInit(java.io.InputStream dstream,
                   int startline,
                   int startcolumn,
                   int buffersize)

Specified by:

ReInit in interface CharStream

ReInit

public void ReInit(java.io.InputStream dstream,
                   int startline,
                   int startcolumn)

Specified by:

ReInit in interface CharStream

GetImage

public final java.lang.String GetImage()

Description copied from 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.

Specified by:

GetImage in interface CharStream

GetSuffix

public final char[] GetSuffix(int len)

Description copied from 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(); }

Specified by:

GetSuffix in interface CharStream

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 newLine,
                                  int newCol)

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