org.python.parser.ReaderCharStream Maven / Gradle / Ivy
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Jython is an implementation of the high-level, dynamic, object-oriented
language Python written in 100% Pure Java, and seamlessly integrated with
the Java platform. It thus allows you to run Python on any Java platform.
package org.python.parser;
/**
* An implementation of interface CharStream, where the data is read from
* a Reader.
* This file started life as a copy of ASCII_CharStream.java.
*/
public final class ReaderCharStream implements CharStream
{
public static final boolean staticFlag = false;
int bufsize;
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;
private final 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;
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 += 2048;
available = bufsize;
tokenBegin = 0;
}
private final void FillBuff() throws java.io.IOException
{
if (maxNextCharInd == available)
{
if (available == bufsize)
{
if (tokenBegin > 2048)
{
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) < 2048)
ExpandBuff(true);
else
available = tokenBegin;
}
int i;
try {
if ((i = inputStream.read(buffer, maxNextCharInd,
available - maxNextCharInd)) == -1)
{
inputStream.close();
throw new java.io.IOException();
}
else
maxNextCharInd += i;
return;
}
catch(java.io.IOException e) {
--bufpos;
backup(0);
if (tokenBegin == -1)
tokenBegin = bufpos;
throw e;
}
}
public final char BeginToken() throws java.io.IOException
{
tokenBegin = -1;
char c = readChar();
tokenBegin = bufpos;
return c;
}
private final 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;
}
public final char readChar() throws java.io.IOException
{
if (inBuf > 0)
{
--inBuf;
return buffer[(bufpos == bufsize - 1) ? (bufpos = 0) : ++bufpos];
}
if (++bufpos >= maxNextCharInd)
FillBuff();
char c = buffer[bufpos];
UpdateLineColumn(c);
return (c);
}
/**
* @deprecated
* @see #getEndColumn
*/
public final int getColumn() {
return bufcolumn[bufpos];
}
/**
* @deprecated
* @see #getEndLine
*/
public final int getLine() {
return bufline[bufpos];
}
public final int getEndColumn() {
return bufcolumn[bufpos];
}
public final int getEndLine() {
return bufline[bufpos];
}
public final int getBeginColumn() {
return bufcolumn[tokenBegin];
}
public final int getBeginLine() {
return bufline[tokenBegin];
}
public final void backup(int amount) {
inBuf += amount;
if ((bufpos -= amount) < 0)
bufpos += bufsize;
}
public ReaderCharStream(java.io.Reader dstream)
{
inputStream = dstream;
line = 1;
column = 0;
available = bufsize = 4096;
buffer = new char[bufsize];
bufline = new int[bufsize];
bufcolumn = new int[bufsize];
}
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);
}
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;
}
public void Done()
{
buffer = null;
bufline = null;
bufcolumn = null;
}
/**
* Method to adjust line and column numbers for the start of a token.
*/
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];
}
}