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/* Generated by: ParserGeneratorCC: Do not edit this line. AbstractCharStream.java Version 1.1 */
/* ParserGeneratorCCOptions:SUPPORT_CLASS_VISIBILITY_PUBLIC=true */
package com.clickhouse.jdbc.parser;
/**
* An implementation of interface CharStream, where the stream is assumed to
* contain only ASCII characters (without unicode processing).
*/
public
abstract class AbstractCharStream
implements CharStream
{
/** Default buffer size if nothing is specified */
public static final int DEFAULT_BUF_SIZE = 4096;
static final int hexval (final char c) throws java.io.IOException
{
switch (c)
{
case '0':
return 0;
case '1':
return 1;
case '2':
return 2;
case '3':
return 3;
case '4':
return 4;
case '5':
return 5;
case '6':
return 6;
case '7':
return 7;
case '8':
return 8;
case '9':
return 9;
case 'a':
case 'A':
return 10;
case 'b':
case 'B':
return 11;
case 'c':
case 'C':
return 12;
case 'd':
case 'D':
return 13;
case 'e':
case 'E':
return 14;
case 'f':
case 'F':
return 15;
default:
throw new java.io.IOException ("Invalid hex char '" + c + "' (=" + (int) c + ") provided!");
}
}
/** Tab size for formatting. Usually in the range 1 to 8. */
private int m_nTabSize = 1;
/** Internal circular buffer */
protected char[] buffer;
/** Overall buffer size - same as buffer.length */
protected int bufsize;
/** Current read position in buffer. */
protected int bufpos;
/** The number of unoccupied buffer array positions */
protected int available;
/** The first array index (of `buffer`) that the current token starts */
protected int tokenBegin;
/** Characters in the backup/pushBack buffer */
protected int inBuf;
protected int maxNextCharInd;
private int[] m_aBufLine;
private int[] m_aBufColumn;
// Current line number
private int m_nLineNo;
// Current column number
private int m_nColumnNo;
// Was the previous character a "\r" char?
private boolean m_bPrevCharIsCR;
// Was the previous character a "\n" char?
private boolean m_bPrevCharIsLF;
// Is line/column tracking enabled?
private boolean m_bTrackLineColumn = true;
/** Constructor. */
public AbstractCharStream(final int nStartLine,
final int nStartColumn,
final int nBufferSize)
{
reInit (nStartLine, nStartColumn, nBufferSize);
}
/** Reinitialise. */
public final void reInit(final int nStartLine,
final int nStartColumn,
final int nBufferSize)
{
m_nLineNo = nStartLine;
m_nColumnNo = nStartColumn - 1;
m_bPrevCharIsCR = false;
m_bPrevCharIsLF = false;
if (buffer == null || nBufferSize != buffer.length)
{
bufsize = nBufferSize;
available = nBufferSize;
buffer = new char[nBufferSize];
m_aBufLine = new int[nBufferSize];
m_aBufColumn = new int[nBufferSize];
}
maxNextCharInd = 0;
inBuf = 0;
tokenBegin = 0;
bufpos = -1;
}
/**
* Read from the underlying stream.
* @param aBuf the buffer to be filled
* @param nOfs The offset into the buffer. 0-based
* @param nLen Number of chars to read.
* @return Number of effective chars read, or -1 on error.
*/
protected abstract int streamRead (char[] aBuf, int nOfs, int nLen) throws java.io.IOException;
/**
* Close the underlying stream.
* @throws java.io.IOException If closing fails.
*/
protected abstract void streamClose () throws java.io.IOException;
// Override this method if you need more aggressive buffer size expansion
protected int getBufSizeAfterExpansion ()
{
// Double the size by default
return bufsize * 2;
}
protected void expandBuff (final boolean bWrapAround)
{
// Get the new buffer size
final int nNewBufSize = getBufSizeAfterExpansion ();
final char[] newbuffer = new char[nNewBufSize];
final int[] newbufline = new int[nNewBufSize];
final int[] newbufcolumn = new int[nNewBufSize];
// Number of chars to be preserved
final int nPreservedChars = bufsize - tokenBegin;
if (bWrapAround)
{
// Move from offset "tokenBegin" to offset 0
// arraycopy(src, srcPos, dest, destPos, length)
// copy the "tail end" to the "start" (index 0) of the new buffer array
System.arraycopy(buffer, tokenBegin, newbuffer, 0, nPreservedChars);
// copy the remaining "wrap around" content of the buffer from the start of the original buffer (starting at srcPos index 0)
System.arraycopy(buffer, 0, newbuffer, nPreservedChars, bufpos);
// swap the new buffer in place of the old buffer
buffer = newbuffer;
System.arraycopy(m_aBufLine, tokenBegin, newbufline, 0, nPreservedChars);
System.arraycopy(m_aBufLine, 0, newbufline, nPreservedChars, bufpos);
m_aBufLine = newbufline;
System.arraycopy(m_aBufColumn, tokenBegin, newbufcolumn, 0, nPreservedChars);
System.arraycopy(m_aBufColumn, 0, newbufcolumn, nPreservedChars, bufpos);
m_aBufColumn = newbufcolumn;
bufpos += nPreservedChars;
maxNextCharInd = bufpos;
}
else
{
// Move from offset "tokenBegin" to offset 0
System.arraycopy(buffer, tokenBegin, newbuffer, 0, nPreservedChars);
buffer = newbuffer;
System.arraycopy(m_aBufLine, tokenBegin, newbufline, 0, nPreservedChars);
m_aBufLine = newbufline;
System.arraycopy(m_aBufColumn, tokenBegin, newbufcolumn, 0, nPreservedChars);
m_aBufColumn = newbufcolumn;
bufpos -= tokenBegin;
maxNextCharInd = bufpos;
}
// Increase buffer size
bufsize = nNewBufSize;
available = nNewBufSize;
tokenBegin = 0;
}
protected final void internalAdjustBuffSize()
{
final int nHalfBufferSize = bufsize / 2;
if (available == bufsize)
{
if (tokenBegin < 0)
{
// If this method is called from "beginToken()"
// Just refill the buffer from the start
bufpos = 0;
maxNextCharInd = 0;
}
else
if (tokenBegin > nHalfBufferSize)
{
// The token started in the second half - fill the front part
bufpos = 0;
maxNextCharInd = 0;
// Available bytes are > 50%
available = tokenBegin;
}
else
{
// Token starts in the first half
// just append to existing buffer
expandBuff (false);
}
}
else
{
// A token was read across array boundaries
if (available > tokenBegin)
{
available = bufsize;
}
else
if ((tokenBegin - available) < nHalfBufferSize)
{
expandBuff (true);
}
else
{
available = tokenBegin;
}
}
}
protected void fillBuff() throws java.io.IOException
{
if (maxNextCharInd == available)
internalAdjustBuffSize();
try
{
// Read from underlying stream
final int nCharsRead = streamRead (buffer, maxNextCharInd, available - maxNextCharInd);
if (nCharsRead == -1)
{
// We reached the end of the file
streamClose ();
// Caught down below and re-thrown
throw new java.io.IOException("PGCC end of stream");
}
maxNextCharInd += nCharsRead;
}
catch (final java.io.IOException ex)
{
--bufpos;
// ?What is the reason of this? Backup of 0 does nothing
backup (0);
if (tokenBegin == -1)
{
// Error occurred in "beginToken()"
tokenBegin = bufpos;
}
throw ex;
}
}
protected final void internalSetBufLineColumn (final int nLine, final int nColumn)
{
m_aBufLine[bufpos] = nLine;
m_aBufColumn[bufpos] = nColumn;
}
protected final void internalUpdateLineColumn(final char c)
{
m_nColumnNo++;
if (m_bPrevCharIsLF)
{
// It's a "\r\n" or "\n"
// Start of a new line
m_bPrevCharIsLF = false;
m_nColumnNo = 1;
m_nLineNo++;
}
else
if (m_bPrevCharIsCR)
{
m_bPrevCharIsCR = false;
if (c == '\n')
{
// It's a "\r\n"
m_bPrevCharIsLF = true;
}
else
{
// It's only a "\r"
m_nColumnNo = 1;
m_nLineNo++;
}
}
switch (c)
{
case '\r':
m_bPrevCharIsCR = true;
break;
case '\n':
m_bPrevCharIsLF = true;
break;
case '\t':
m_nColumnNo--;
m_nColumnNo += (m_nTabSize - (m_nColumnNo % m_nTabSize));
break;
}
internalSetBufLineColumn (m_nLineNo, m_nColumnNo);
}
public char readChar() throws java.io.IOException
{
if (inBuf > 0)
{
// Something is left from last backup
--inBuf;
++bufpos;
if (bufpos == bufsize)
{
// Buffer overflow
bufpos = 0;
}
return buffer[bufpos];
}
++bufpos;
if (bufpos >= maxNextCharInd)
fillBuff();
final char c = buffer[bufpos];
if (m_bTrackLineColumn)
internalUpdateLineColumn(c);
return c;
}
public char beginToken() throws java.io.IOException
{
tokenBegin = -1;
final char c = readChar();
tokenBegin = bufpos;
return c;
}
public int getBeginColumn ()
{
return m_aBufColumn[tokenBegin];
}
public int getBeginLine ()
{
return m_aBufLine[tokenBegin];
}
public int getEndColumn ()
{
return m_aBufColumn[bufpos];
}
public int getEndLine ()
{
return m_aBufLine[bufpos];
}
public void backup (final int nAmount)
{
if (nAmount > bufsize)
throw new IllegalStateException ("Cannot back " + nAmount + " chars which is larger than the internal buffer size (" + bufsize + ")");
inBuf += nAmount;
bufpos -= nAmount;
if (bufpos < 0)
{
// Buffer underflow (modulo)
bufpos += bufsize;
}
}
public String getImage()
{
if (bufpos >= tokenBegin)
{
// from tokenBegin to bufpos
return new String (buffer, tokenBegin, bufpos - tokenBegin + 1);
}
// from tokenBegin to bufsize, and from 0 to bufpos
return new String (buffer, tokenBegin, bufsize - tokenBegin) +
new String (buffer, 0, bufpos + 1);
}
public char[] getSuffix (final int len)
{
char[] ret = new char[len];
if ((bufpos + 1) >= len)
{
// one piece
System.arraycopy(buffer, bufpos - len + 1, ret, 0, len);
}
else
{
// Wrap around
final int nPart1 = len - bufpos - 1;
System.arraycopy(buffer, bufsize - nPart1, ret, 0, nPart1);
System.arraycopy(buffer, 0, ret, nPart1, bufpos + 1);
}
return ret;
}
public void done()
{
buffer = null;
m_aBufLine = null;
m_aBufColumn = null;
}
public final int getTabSize()
{
return m_nTabSize;
}
public final void setTabSize (final int nTabSize)
{
m_nTabSize = nTabSize;
}
/**
* Method to adjust line and column numbers for the start of a token.
* This is used internally to
*/
public final void adjustBeginLineColumn(final int nNewLine, final int newCol)
{
int start = tokenBegin;
int newLine = nNewLine;
int len;
if (bufpos >= tokenBegin)
{
len = bufpos - tokenBegin + inBuf + 1;
}
else
{
len = bufsize - tokenBegin + bufpos + 1 + inBuf;
}
int i = 0;
int j = 0;
int k = 0;
int nextColDiff = 0;
int columnDiff = 0;
// TODO disassemble meaning and split up
while (i < len && m_aBufLine[j = start % bufsize] == m_aBufLine[k = ++start % bufsize])
{
m_aBufLine[j] = newLine;
nextColDiff = columnDiff + m_aBufColumn[k] - m_aBufColumn[j];
m_aBufColumn[j] = newCol + columnDiff;
columnDiff = nextColDiff;
i++;
}
if (i < len)
{
m_aBufLine[j] = newLine++;
m_aBufColumn[j] = newCol + columnDiff;
while (i++ < len)
{
// TODO disassemble meaning and split up
if (m_aBufLine[j = start % bufsize] != m_aBufLine[++start % bufsize])
m_aBufLine[j] = newLine++;
else
m_aBufLine[j] = newLine;
}
}
m_nLineNo = m_aBufLine[j];
m_nColumnNo = m_aBufColumn[j];
}
/**
* @return the current line number. 0-based.
*/
protected final int getLine ()
{
return m_nLineNo;
}
/**
* @return the current column number. 0-based.
*/
protected final int getColumn ()
{
return m_nColumnNo;
}
public final boolean isTrackLineColumn ()
{
return m_bTrackLineColumn;
}
public final void setTrackLineColumn (final boolean bTrackLineColumn)
{
m_bTrackLineColumn = bTrackLineColumn;
}
}
/* ParserGeneratorCC - OriginalChecksum=3b4ebf2d1bb3be381eb7f7ab3bdaf0f5 (do not edit this line) */