org.apache.velocity.runtime.parser.VelocityCharStream Maven / Gradle / Ivy
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package org.apache.velocity.runtime.parser;
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
/**
* An implementation of interface CharStream, where the stream is assumed to
* contain only ASCII characters (without unicode processing).
*
* NOTE : This class was originally an ASCII_CharStream autogenerated
* by Javacc. It was then modified via changing class name with appropriate
* fixes for CTORS, and mods to readChar().
*
* This is safe because we *always* use Reader with this class, and never a
* InputStream. This guarantees that we have a correct stream of 16-bit
* chars - all encoding transformations have been done elsewhere, so we
* believe that there is no risk in doing this. Time will tell :)
*
*/
public final class VelocityCharStream
implements CharStream
{
public static final boolean staticFlag = false;
int bufsize;
private int nextBufExpand;
int available;
int tokenBegin;
public int bufpos = -1;
private int bufline[];
private int bufcolumn[];
private int column = 0;
private int line = 1;
private boolean prevCharIsCR = false;
private boolean prevCharIsLF = false;
private java.io.Reader inputStream;
private char[] buffer;
private int maxNextCharInd = 0;
private int inBuf = 0;
/* CB - to properly handle EOF *inside* javacc lexer,
* we send a 'file separator' ascii char *just before* EOF
* (see https://en.wikipedia.org/wiki/Delimiter#ASCII_delimited_text)
*/
private boolean beforeEOF = false;
private static char END_OF_FILE = '\u001C';
private void ExpandBuff(boolean wrapAround)
{
char[] newbuffer = new char[bufsize + nextBufExpand];
int newbufline[] = new int[bufsize + nextBufExpand];
int newbufcolumn[] = new int[bufsize + nextBufExpand];
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;
maxNextCharInd = (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;
maxNextCharInd = (bufpos -= tokenBegin);
}
}
catch (Throwable t)
{
throw new Error(t.getMessage());
}
bufsize += nextBufExpand;
nextBufExpand = bufsize;
available = bufsize;
tokenBegin = 0;
}
private void FillBuff() throws java.io.IOException
{
if (maxNextCharInd == available)
{
if (available == bufsize)
{
if (tokenBegin > nextBufExpand)
{
bufpos = maxNextCharInd = 0;
available = tokenBegin;
}
else if (tokenBegin < 0)
{
bufpos = maxNextCharInd = 0;
}
else
{
ExpandBuff(false);
}
}
else if (available > tokenBegin)
{
available = bufsize;
}
else if ((tokenBegin - available) < nextBufExpand)
{
ExpandBuff(true);
}
else
{
available = tokenBegin;
}
}
int i;
try
{
if ((i = inputStream.read(buffer, maxNextCharInd,
available - maxNextCharInd)) == -1)
{
if (beforeEOF)
{
inputStream.close();
throw new java.io.IOException();
}
buffer[maxNextCharInd++] = END_OF_FILE;
beforeEOF = true;
}
else
{
maxNextCharInd += i;
}
}
catch(java.io.IOException e)
{
--bufpos;
backup(0);
if (tokenBegin == -1)
{
tokenBegin = bufpos;
}
throw e;
}
}
/**
* @see org.apache.velocity.runtime.parser.CharStream#BeginToken()
*/
@Override
public final char BeginToken() throws java.io.IOException
{
tokenBegin = -1;
char c = readChar();
tokenBegin = bufpos;
return c;
}
private 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;
}
/**
* @see org.apache.velocity.runtime.parser.CharStream#readChar()
*/
@Override
public final char readChar() throws java.io.IOException
{
if (inBuf > 0)
{
--inBuf;
/*
* was : return (char)((char)0xff & buffer[(bufpos == bufsize - 1) ? (bufpos = 0) : ++bufpos]);
*/
return buffer[(bufpos == bufsize - 1) ? (bufpos = 0) : ++bufpos];
}
if (++bufpos >= maxNextCharInd)
{
FillBuff();
}
/*
* was : char c = (char)((char)0xff & buffer[bufpos]);
*/
char c = buffer[bufpos];
UpdateLineColumn(c);
return (c);
}
/**
* @see org.apache.velocity.runtime.parser.CharStream#getEndColumn()
*/
@Override
public final int getEndColumn()
{
return bufcolumn[bufpos];
}
/**
* @see org.apache.velocity.runtime.parser.CharStream#getEndLine()
*/
@Override
public final int getEndLine()
{
return bufline[bufpos];
}
/**
* @see org.apache.velocity.runtime.parser.CharStream#getBeginColumn()
*/
@Override
public final int getBeginColumn()
{
return bufcolumn[tokenBegin];
}
/**
* @see org.apache.velocity.runtime.parser.CharStream#getBeginLine()
*/
@Override
public final int getBeginLine()
{
return bufline[tokenBegin];
}
/**
* @see org.apache.velocity.runtime.parser.CharStream#backup(int)
*/
@Override
public final void backup(int amount)
{
inBuf += amount;
if ((bufpos -= amount) < 0)
bufpos += bufsize;
}
/**
* @param dstream
* @param startline
* @param startcolumn
* @param buffersize
*/
public VelocityCharStream(java.io.Reader dstream, int startline,
int startcolumn, int buffersize)
{
inputStream = dstream;
line = startline;
column = startcolumn - 1;
available = bufsize = nextBufExpand = buffersize;
buffer = new char[buffersize];
bufline = new int[buffersize];
bufcolumn = new int[buffersize];
}
/**
* @param dstream
* @param startline
* @param startcolumn
*/
public VelocityCharStream(java.io.Reader dstream, int startline,
int startcolumn)
{
this(dstream, startline, startcolumn, 4096);
}
/**
* @param dstream
* @param startline
* @param startcolumn
* @param buffersize
*/
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 = nextBufExpand = buffersize;
buffer = new char[buffersize];
bufline = new int[buffersize];
bufcolumn = new int[buffersize];
}
prevCharIsLF = prevCharIsCR = false;
tokenBegin = inBuf = maxNextCharInd = 0;
bufpos = -1;
beforeEOF = false;
}
/**
* @param dstream
* @param startline
* @param startcolumn
*/
public void ReInit(java.io.Reader dstream, int startline,
int startcolumn)
{
ReInit(dstream, startline, startcolumn, 4096);
}
/**
* @param dstream
* @param startline
* @param startcolumn
* @param buffersize
*/
public VelocityCharStream(java.io.InputStream dstream, int startline,
int startcolumn, int buffersize)
{
this(new java.io.InputStreamReader(dstream), startline, startcolumn, buffersize);
}
/**
* @param dstream
* @param startline
* @param startcolumn
*/
public VelocityCharStream(java.io.InputStream dstream, int startline,
int startcolumn)
{
this(dstream, startline, startcolumn, 4096);
}
/**
* @param dstream
* @param startline
* @param startcolumn
* @param buffersize
*/
public void ReInit(java.io.InputStream dstream, int startline,
int startcolumn, int buffersize)
{
ReInit(new java.io.InputStreamReader(dstream), startline, startcolumn, buffersize);
}
/**
* @param dstream
* @param startline
* @param startcolumn
*/
public void ReInit(java.io.InputStream dstream, int startline,
int startcolumn)
{
ReInit(dstream, startline, startcolumn, 4096);
}
/**
* @see org.apache.velocity.runtime.parser.CharStream#GetImage()
*/
@Override
public final 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);
}
}
/**
* @see org.apache.velocity.runtime.parser.CharStream#GetSuffix(int)
*/
@Override
public final 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;
}
/**
* @see org.apache.velocity.runtime.parser.CharStream#Done()
*/
@Override
public void Done()
{
buffer = null;
bufline = null;
bufcolumn = null;
}
/**
* Method to adjust line and column numbers for the start of a token.
* @param newLine
* @param newCol
*/
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];
}
}