org.eclipse.viatra2.imports.vtml/src/org/eclipse/viatra2/imports/vtml/JavaCharStream.java - viatra/org.eclipse.viatra2.vpm - Git at Google

 /*******************************************************************************
  * Copyright (c) 2004-2008 Andras Balogh and Daniel Varro
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *    Andras Balogh - initial API and implementation
  *******************************************************************************/

  package org.eclipse.viatra2.imports.vtml;

 /**
  * An implementation of interface CharStream, where the stream is assumed to
  * contain only ASCII characters (with java-like unicode escape processing).
  */

 public class JavaCharStream
 {
   public static final boolean staticFlag = true;
   static final int hexval(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;
     }

     throw new java.io.IOException(); // Should never come here
   }

   static public int bufpos = -1;
   static int bufsize;
   static int available;
   static int tokenBegin;
   static protected int bufline[];
   static protected int bufcolumn[];

   static protected int column = 0;
   static protected int line = 1;

   static protected boolean prevCharIsCR = false;
   static protected boolean prevCharIsLF = false;

   static protected java.io.Reader inputStream;

   static protected char[] nextCharBuf;
   static protected char[] buffer;
   static protected int maxNextCharInd = 0;
   static protected int nextCharInd = -1;
   static protected int inBuf = 0;

   static protected void ExpandBuff(boolean wrapAround)
   {
      char[] newbuffer = new char[bufsize + 2048];
      int newbufline[] = new int[bufsize + 2048];
      int newbufcolumn[] = new int[bufsize + 2048];

      try
      {
         if (wrapAround)
         {
            System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
            System.arraycopy(buffer, 0, newbuffer,
                                              bufsize - tokenBegin, bufpos);
            buffer = newbuffer;

            System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
            System.arraycopy(bufline, 0, newbufline, bufsize - tokenBegin, bufpos);
            bufline = newbufline;

            System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
            System.arraycopy(bufcolumn, 0, newbufcolumn, bufsize - tokenBegin, bufpos);
            bufcolumn = newbufcolumn;

            bufpos += (bufsize - tokenBegin);
         }
         else
         {
            System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
            buffer = newbuffer;

            System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
            bufline = newbufline;

            System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
            bufcolumn = newbufcolumn;

            bufpos -= tokenBegin;
         }
      }
      catch (Throwable t)
      {
         throw new Error(t.getMessage());
      }

      available = (bufsize += 2048);
      tokenBegin = 0;
   }

   static protected void FillBuff() throws java.io.IOException
   {
      int i;
      if (maxNextCharInd == 4096)
         maxNextCharInd = nextCharInd = 0;

      try {
         if ((i = inputStream.read(nextCharBuf, maxNextCharInd,
                                             4096 - maxNextCharInd)) == -1)
         {
            inputStream.close();
            throw new java.io.IOException();
         }
         else
            maxNextCharInd += i;
         return;
      }
      catch(java.io.IOException e) {
         if (bufpos != 0)
         {
            --bufpos;
            backup(0);
         }
         else
         {
            bufline[bufpos] = line;
            bufcolumn[bufpos] = column;
         }
         throw e;
      }
   }

   static protected char ReadByte() throws java.io.IOException
   {
      if (++nextCharInd >= maxNextCharInd)
         FillBuff();

      return nextCharBuf[nextCharInd];
   }

   static public char BeginToken() throws java.io.IOException
   {
      if (inBuf > 0)
      {
         --inBuf;

         if (++bufpos == bufsize)
            bufpos = 0;

         tokenBegin = bufpos;
         return buffer[bufpos];
      }

      tokenBegin = 0;
      bufpos = -1;

      return readChar();
   }

   static protected void AdjustBuffSize()
   {
      if (available == bufsize)
      {
         if (tokenBegin > 2048)
         {
            bufpos = 0;
            available = tokenBegin;
         }
         else
            ExpandBuff(false);
      }
      else if (available > tokenBegin)
         available = bufsize;
      else if ((tokenBegin - available) < 2048)
         ExpandBuff(true);
      else
         available = tokenBegin;
   }

   static protected void UpdateLineColumn(char c)
   {
      column++;

      if (prevCharIsLF)
      {
         prevCharIsLF = false;
         line += (column = 1);
      }
      else if (prevCharIsCR)
      {
         prevCharIsCR = false;
         if (c == '\n')
         {
            prevCharIsLF = true;
         }
         else
            line += (column = 1);
      }

      switch (c)
      {
         case '\r' :
            prevCharIsCR = true;
            break;
         case '\n' :
            prevCharIsLF = true;
            break;
         case '\t' :
            column--;
            column += (8 - (column & 07));
            break;
         default :
            break;
      }

      bufline[bufpos] = line;
      bufcolumn[bufpos] = column;
   }

   static public char readChar() throws java.io.IOException
   {
      if (inBuf > 0)
      {
         --inBuf;

         if (++bufpos == bufsize)
            bufpos = 0;

         return buffer[bufpos];
      }

      char c;

      if (++bufpos == available)
         AdjustBuffSize();

      if ((buffer[bufpos] = c = ReadByte()) == '\\')
      {
         UpdateLineColumn(c);

         int backSlashCnt = 1;

         for (;;) // Read all the backslashes
         {
            if (++bufpos == available)
               AdjustBuffSize();

            try
            {
               if ((buffer[bufpos] = c = ReadByte()) != '\\')
               {
                  UpdateLineColumn(c);
                  // found a non-backslash char.
                  if ((c == 'u') && ((backSlashCnt & 1) == 1))
                  {
                     if (--bufpos < 0)
                        bufpos = bufsize - 1;

                     break;
                  }

                  backup(backSlashCnt);
                  return '\\';
               }
            }
            catch(java.io.IOException e)
            {
               if (backSlashCnt > 1)
                  backup(backSlashCnt);

               return '\\';
            }

            UpdateLineColumn(c);
            backSlashCnt++;
         }

         // Here, we have seen an odd number of backslash's followed by a 'u'
         try
         {
            while ((c = ReadByte()) == 'u')
               ++column;

            buffer[bufpos] = c = (char)(hexval(c) << 12 |
                                        hexval(ReadByte()) << 8 |
                                        hexval(ReadByte()) << 4 |
                                        hexval(ReadByte()));

            column += 4;
         }
         catch(java.io.IOException e)
         {
            throw new Error("Invalid escape character at line " + line +
                                          " column " + column + ".");
         }

         if (backSlashCnt == 1)
            return c;
         else
         {
            backup(backSlashCnt - 1);
            return '\\';
         }
      }
      else
      {
         UpdateLineColumn(c);
         return (c);
      }
   }

   /**
    * @deprecated
    * @see #getEndColumn
    */

   static public int getColumn() {
      return bufcolumn[bufpos];
   }

   /**
    * @deprecated
    * @see #getEndLine
    */

   static public int getLine() {
      return bufline[bufpos];
   }

   static public int getEndColumn() {
      return bufcolumn[bufpos];
   }

   static public int getEndLine() {
      return bufline[bufpos];
   }

   static public int getBeginColumn() {
      return bufcolumn[tokenBegin];
   }

   static public int getBeginLine() {
      return bufline[tokenBegin];
   }

   static public void backup(int amount) {

     inBuf += amount;
     if ((bufpos -= amount) < 0)
        bufpos += bufsize;
   }

   public JavaCharStream(java.io.Reader dstream,
                  int startline, int startcolumn, int buffersize)
   {
     if (inputStream != null)
        throw new Error("\n   ERROR: Second call to the constructor of a static JavaCharStream.  You must\n" +
        "       either use ReInit() or set the JavaCC option STATIC to false\n" +
        "       during the generation of this class.");
     inputStream = dstream;
     line = startline;
     column = startcolumn - 1;

     available = bufsize = buffersize;
     buffer = new char[buffersize];
     bufline = new int[buffersize];
     bufcolumn = new int[buffersize];
     nextCharBuf = new char[4096];
   }

   public JavaCharStream(java.io.Reader dstream,
                                         int startline, int startcolumn)
   {
      this(dstream, startline, startcolumn, 4096);
   }

   public JavaCharStream(java.io.Reader dstream)
   {
      this(dstream, 1, 1, 4096);
   }
   public void ReInit(java.io.Reader dstream,
                  int startline, int startcolumn, int buffersize)
   {
     inputStream = dstream;
     line = startline;
     column = startcolumn - 1;

     if (buffer == null || buffersize != buffer.length)
     {
       available = bufsize = buffersize;
       buffer = new char[buffersize];
       bufline = new int[buffersize];
       bufcolumn = new int[buffersize];
       nextCharBuf = new char[4096];
     }
     prevCharIsLF = prevCharIsCR = false;
     tokenBegin = inBuf = maxNextCharInd = 0;
     nextCharInd = bufpos = -1;
   }

   public void ReInit(java.io.Reader dstream,
                                         int startline, int startcolumn)
   {
      ReInit(dstream, startline, startcolumn, 4096);
   }

   public void ReInit(java.io.Reader dstream)
   {
      ReInit(dstream, 1, 1, 4096);
   }
   public JavaCharStream(java.io.InputStream dstream, int startline,
   int startcolumn, int buffersize)
   {
      this(new java.io.InputStreamReader(dstream), startline, startcolumn, 4096);
   }

   public JavaCharStream(java.io.InputStream dstream, int startline,
                                                            int startcolumn)
   {
      this(dstream, startline, startcolumn, 4096);
   }

   public JavaCharStream(java.io.InputStream dstream)
   {
      this(dstream, 1, 1, 4096);
   }

   public void ReInit(java.io.InputStream dstream, int startline,
   int startcolumn, int buffersize)
   {
      ReInit(new java.io.InputStreamReader(dstream), startline, startcolumn, 4096);
   }
   public void ReInit(java.io.InputStream dstream, int startline,
                                                            int startcolumn)
   {
      ReInit(dstream, startline, startcolumn, 4096);
   }
   public void ReInit(java.io.InputStream dstream)
   {
      ReInit(dstream, 1, 1, 4096);
   }

   static public String GetImage()
   {
      if (bufpos >= tokenBegin)
         return new String(buffer, tokenBegin, bufpos - tokenBegin + 1);
      else
         return new String(buffer, tokenBegin, bufsize - tokenBegin) +
                               new String(buffer, 0, bufpos + 1);
   }

   static public char[] GetSuffix(int len)
   {
      char[] ret = new char[len];

      if ((bufpos + 1) >= len)
         System.arraycopy(buffer, bufpos - len + 1, ret, 0, len);
      else
      {
         System.arraycopy(buffer, bufsize - (len - bufpos - 1), ret, 0,
                                                           len - bufpos - 1);
         System.arraycopy(buffer, 0, ret, len - bufpos - 1, bufpos + 1);
      }

      return ret;
   }

   static public void Done()
   {
      nextCharBuf = null;
      buffer = null;
      bufline = null;
      bufcolumn = null;
   }

   /**
    * Method to adjust line and column numbers for the start of a token.
    */
   static public void adjustBeginLineColumn(int newLine, int newCol)
   {
      int start = tokenBegin;
      int len;

      if (bufpos >= tokenBegin)
      {
         len = bufpos - tokenBegin + inBuf + 1;
      }
      else
      {
         len = bufsize - tokenBegin + bufpos + 1 + inBuf;
      }

      int i = 0, j = 0, k = 0;
      int nextColDiff = 0, columnDiff = 0;

      while (i < len &&
             bufline[j = start % bufsize] == bufline[k = ++start % bufsize])
      {
         bufline[j] = newLine;
         nextColDiff = columnDiff + bufcolumn[k] - bufcolumn[j];
         bufcolumn[j] = newCol + columnDiff;
         columnDiff = nextColDiff;
         i++;
      }

      if (i < len)
      {
         bufline[j] = newLine++;
         bufcolumn[j] = newCol + columnDiff;

         while (i++ < len)
         {
            if (bufline[j = start % bufsize] != bufline[++start % bufsize])
               bufline[j] = newLine++;
            else
               bufline[j] = newLine;
         }
      }

      line = bufline[j];
      column = bufcolumn[j];
   }

 }
	/*******************************************************************************
	* Copyright (c) 2004-2008 Andras Balogh and Daniel Varro
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* Andras Balogh - initial API and implementation
	*******************************************************************************/

	package org.eclipse.viatra2.imports.vtml;

	/**
	* An implementation of interface CharStream, where the stream is assumed to
	* contain only ASCII characters (with java-like unicode escape processing).
	*/

	public class JavaCharStream
	{
	public static final boolean staticFlag = true;
	static final int hexval(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;
	}

	throw new java.io.IOException(); // Should never come here
	}

	static public int bufpos = -1;
	static int bufsize;
	static int available;
	static int tokenBegin;
	static protected int bufline[];
	static protected int bufcolumn[];

	static protected int column = 0;
	static protected int line = 1;

	static protected boolean prevCharIsCR = false;
	static protected boolean prevCharIsLF = false;

	static protected java.io.Reader inputStream;

	static protected char[] nextCharBuf;
	static protected char[] buffer;
	static protected int maxNextCharInd = 0;
	static protected int nextCharInd = -1;
	static protected int inBuf = 0;

	static protected void ExpandBuff(boolean wrapAround)
	{
	char[] newbuffer = new char[bufsize + 2048];
	int newbufline[] = new int[bufsize + 2048];
	int newbufcolumn[] = new int[bufsize + 2048];

	try
	{
	if (wrapAround)
	{
	System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
	System.arraycopy(buffer, 0, newbuffer,
	bufsize - tokenBegin, bufpos);
	buffer = newbuffer;

	System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
	System.arraycopy(bufline, 0, newbufline, bufsize - tokenBegin, bufpos);
	bufline = newbufline;

	System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
	System.arraycopy(bufcolumn, 0, newbufcolumn, bufsize - tokenBegin, bufpos);
	bufcolumn = newbufcolumn;

	bufpos += (bufsize - tokenBegin);
	}
	else
	{
	System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
	buffer = newbuffer;

	System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
	bufline = newbufline;

	System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
	bufcolumn = newbufcolumn;

	bufpos -= tokenBegin;
	}
	}
	catch (Throwable t)
	{
	throw new Error(t.getMessage());
	}

	available = (bufsize += 2048);
	tokenBegin = 0;
	}

	static protected void FillBuff() throws java.io.IOException
	{
	int i;
	if (maxNextCharInd == 4096)
	maxNextCharInd = nextCharInd = 0;

	try {
	if ((i = inputStream.read(nextCharBuf, maxNextCharInd,
	4096 - maxNextCharInd)) == -1)
	{
	inputStream.close();
	throw new java.io.IOException();
	}
	else
	maxNextCharInd += i;
	return;
	}
	catch(java.io.IOException e) {
	if (bufpos != 0)
	{
	--bufpos;
	backup(0);
	}
	else
	{
	bufline[bufpos] = line;
	bufcolumn[bufpos] = column;
	}
	throw e;
	}
	}

	static protected char ReadByte() throws java.io.IOException
	{
	if (++nextCharInd >= maxNextCharInd)
	FillBuff();

	return nextCharBuf[nextCharInd];
	}

	static public char BeginToken() throws java.io.IOException
	{
	if (inBuf > 0)
	{
	--inBuf;

	if (++bufpos == bufsize)
	bufpos = 0;

	tokenBegin = bufpos;
	return buffer[bufpos];
	}

	tokenBegin = 0;
	bufpos = -1;

	return readChar();
	}

	static protected void AdjustBuffSize()
	{
	if (available == bufsize)
	{
	if (tokenBegin > 2048)
	{
	bufpos = 0;
	available = tokenBegin;
	}
	else
	ExpandBuff(false);
	}
	else if (available > tokenBegin)
	available = bufsize;
	else if ((tokenBegin - available) < 2048)
	ExpandBuff(true);
	else
	available = tokenBegin;
	}

	static protected void UpdateLineColumn(char c)
	{
	column++;

	if (prevCharIsLF)
	{
	prevCharIsLF = false;
	line += (column = 1);
	}
	else if (prevCharIsCR)
	{
	prevCharIsCR = false;
	if (c == '\n')
	{
	prevCharIsLF = true;
	}
	else
	line += (column = 1);
	}

	switch (c)
	{
	case '\r' :
	prevCharIsCR = true;
	break;
	case '\n' :
	prevCharIsLF = true;
	break;
	case '\t' :
	column--;
	column += (8 - (column & 07));
	break;
	default :
	break;
	}

	bufline[bufpos] = line;
	bufcolumn[bufpos] = column;
	}

	static public char readChar() throws java.io.IOException
	{
	if (inBuf > 0)
	{
	--inBuf;

	if (++bufpos == bufsize)
	bufpos = 0;

	return buffer[bufpos];
	}

	char c;

	if (++bufpos == available)
	AdjustBuffSize();

	if ((buffer[bufpos] = c = ReadByte()) == '\\')
	{
	UpdateLineColumn(c);

	int backSlashCnt = 1;

	for (;;) // Read all the backslashes
	{
	if (++bufpos == available)
	AdjustBuffSize();

	try
	{
	if ((buffer[bufpos] = c = ReadByte()) != '\\')
	{
	UpdateLineColumn(c);
	// found a non-backslash char.
	if ((c == 'u') && ((backSlashCnt & 1) == 1))
	{
	if (--bufpos < 0)
	bufpos = bufsize - 1;

	break;
	}

	backup(backSlashCnt);
	return '\\';
	}
	}
	catch(java.io.IOException e)
	{
	if (backSlashCnt > 1)
	backup(backSlashCnt);

	return '\\';
	}

	UpdateLineColumn(c);
	backSlashCnt++;
	}

	// Here, we have seen an odd number of backslash's followed by a 'u'
	try
	{
	while ((c = ReadByte()) == 'u')
	++column;

	buffer[bufpos] = c = (char)(hexval(c) << 12 \|
	hexval(ReadByte()) << 8 \|
	hexval(ReadByte()) << 4 \|
	hexval(ReadByte()));

	column += 4;
	}
	catch(java.io.IOException e)
	{
	throw new Error("Invalid escape character at line " + line +
	" column " + column + ".");
	}

	if (backSlashCnt == 1)
	return c;
	else
	{
	backup(backSlashCnt - 1);
	return '\\';
	}
	}
	else
	{
	UpdateLineColumn(c);
	return (c);
	}
	}

	/**
	* @deprecated
	* @see #getEndColumn
	*/

	static public int getColumn() {
	return bufcolumn[bufpos];
	}

	/**
	* @deprecated
	* @see #getEndLine
	*/

	static public int getLine() {
	return bufline[bufpos];
	}

	static public int getEndColumn() {
	return bufcolumn[bufpos];
	}

	static public int getEndLine() {
	return bufline[bufpos];
	}

	static public int getBeginColumn() {
	return bufcolumn[tokenBegin];
	}

	static public int getBeginLine() {
	return bufline[tokenBegin];
	}

	static public void backup(int amount) {

	inBuf += amount;
	if ((bufpos -= amount) < 0)
	bufpos += bufsize;
	}

	public JavaCharStream(java.io.Reader dstream,
	int startline, int startcolumn, int buffersize)
	{
	if (inputStream != null)
	throw new Error("\n ERROR: Second call to the constructor of a static JavaCharStream. You must\n" +
	" either use ReInit() or set the JavaCC option STATIC to false\n" +
	" during the generation of this class.");
	inputStream = dstream;
	line = startline;
	column = startcolumn - 1;

	available = bufsize = buffersize;
	buffer = new char[buffersize];
	bufline = new int[buffersize];
	bufcolumn = new int[buffersize];
	nextCharBuf = new char[4096];
	}

	public JavaCharStream(java.io.Reader dstream,
	int startline, int startcolumn)
	{
	this(dstream, startline, startcolumn, 4096);
	}

	public JavaCharStream(java.io.Reader dstream)
	{
	this(dstream, 1, 1, 4096);
	}
	public void ReInit(java.io.Reader dstream,
	int startline, int startcolumn, int buffersize)
	{
	inputStream = dstream;
	line = startline;
	column = startcolumn - 1;

	if (buffer == null \|\| buffersize != buffer.length)
	{
	available = bufsize = buffersize;
	buffer = new char[buffersize];
	bufline = new int[buffersize];
	bufcolumn = new int[buffersize];
	nextCharBuf = new char[4096];
	}
	prevCharIsLF = prevCharIsCR = false;
	tokenBegin = inBuf = maxNextCharInd = 0;
	nextCharInd = bufpos = -1;
	}

	public void ReInit(java.io.Reader dstream,
	int startline, int startcolumn)
	{
	ReInit(dstream, startline, startcolumn, 4096);
	}

	public void ReInit(java.io.Reader dstream)
	{
	ReInit(dstream, 1, 1, 4096);
	}
	public JavaCharStream(java.io.InputStream dstream, int startline,
	int startcolumn, int buffersize)
	{
	this(new java.io.InputStreamReader(dstream), startline, startcolumn, 4096);
	}

	public JavaCharStream(java.io.InputStream dstream, int startline,
	int startcolumn)
	{
	this(dstream, startline, startcolumn, 4096);
	}

	public JavaCharStream(java.io.InputStream dstream)
	{
	this(dstream, 1, 1, 4096);
	}

	public void ReInit(java.io.InputStream dstream, int startline,
	int startcolumn, int buffersize)
	{
	ReInit(new java.io.InputStreamReader(dstream), startline, startcolumn, 4096);
	}
	public void ReInit(java.io.InputStream dstream, int startline,
	int startcolumn)
	{
	ReInit(dstream, startline, startcolumn, 4096);
	}
	public void ReInit(java.io.InputStream dstream)
	{
	ReInit(dstream, 1, 1, 4096);
	}

	static public String GetImage()
	{
	if (bufpos >= tokenBegin)
	return new String(buffer, tokenBegin, bufpos - tokenBegin + 1);
	else
	return new String(buffer, tokenBegin, bufsize - tokenBegin) +
	new String(buffer, 0, bufpos + 1);
	}

	static public char[] GetSuffix(int len)
	{
	char[] ret = new char[len];

	if ((bufpos + 1) >= len)
	System.arraycopy(buffer, bufpos - len + 1, ret, 0, len);
	else
	{
	System.arraycopy(buffer, bufsize - (len - bufpos - 1), ret, 0,
	len - bufpos - 1);
	System.arraycopy(buffer, 0, ret, len - bufpos - 1, bufpos + 1);
	}

	return ret;
	}

	static public void Done()
	{
	nextCharBuf = null;
	buffer = null;
	bufline = null;
	bufcolumn = null;
	}

	/**
	* Method to adjust line and column numbers for the start of a token.
	*/
	static public void adjustBeginLineColumn(int newLine, int newCol)
	{
	int start = tokenBegin;
	int len;

	if (bufpos >= tokenBegin)
	{
	len = bufpos - tokenBegin + inBuf + 1;
	}
	else
	{
	len = bufsize - tokenBegin + bufpos + 1 + inBuf;
	}

	int i = 0, j = 0, k = 0;
	int nextColDiff = 0, columnDiff = 0;

	while (i < len &&
	bufline[j = start % bufsize] == bufline[k = ++start % bufsize])
	{
	bufline[j] = newLine;
	nextColDiff = columnDiff + bufcolumn[k] - bufcolumn[j];
	bufcolumn[j] = newCol + columnDiff;
	columnDiff = nextColDiff;
	i++;
	}

	if (i < len)
	{
	bufline[j] = newLine++;
	bufcolumn[j] = newCol + columnDiff;

	while (i++ < len)
	{
	if (bufline[j = start % bufsize] != bufline[++start % bufsize])
	bufline[j] = newLine++;
	else
	bufline[j] = newLine;
	}
	}

	line = bufline[j];
	column = bufcolumn[j];
	}

	}