/**
* Creates a new tokenizer for the specified input stream. The
* tokenizer can be set to process tokens either in
* case-sensitive or case-insensitive mode.
*
* @param input the input stream to read
* @param ignoreCase the character case ignore flag
*
* @since 1.5
*/
public Tokenizer(TextReader input, bool ignoreCase)
{
this.stringDfaMatcher = new StringDFAMatcher(ignoreCase);
this.nfaMatcher = new NFAMatcher(ignoreCase);
this.regExpMatcher = new RegExpMatcher(ignoreCase);
this.buffer = new ReaderBuffer(input);
}
/**
* Creates a new matcher with the specified element.
*
* @param e the base regular expression element
* @param buffer the input character buffer to work with
* @param ignoreCase the character case ignore flag
*/
internal Matcher(Element e, ReaderBuffer buffer, bool ignoreCase) {
this.element = e;
this.buffer = buffer;
this.ignoreCase = ignoreCase;
this.start = 0;
Reset();
}
/**
* Resets this tokenizer for usage with another input stream.
* This method will clear all the internal state in the
* tokenizer as well as close the previous input stream. It
* is normally called in order to reuse a parser and
* tokenizer pair with multiple input streams, thereby
* avoiding the cost of re-analyzing the grammar structures.
*
* @param input the new input stream to read
*
* @see Parser#reset(Reader)
*
* @since 1.5
*/
public void Reset(TextReader input)
{
this.buffer.Dispose();
this.buffer = new ReaderBuffer(input);
this.previousToken = null;
this.lastMatch.Clear();
}
/**
* Searches for matching token patterns at the start of the
* input stream. If a match is found, the token match object
* is updated.
*
* @param buffer the input buffer to check
* @param match the token match to update
*
* @throws IOException if an I/O error occurred
*/
public override void Match(ReaderBuffer buffer, TokenMatch match)
{
TokenPattern res = automaton.Match(buffer, ignoreCase);
if (res != null)
{
match.Update(res.Pattern.Length, res);
}
}
/**
* Searches for matching token patterns at the start of the
* input stream. If a match is found, the token match object
* is updated.
*
* @param buffer the input buffer to check
* @param match the token match to update
*
* @throws IOException if an I/O error occurred
*/
public override void Match(ReaderBuffer buffer, TokenMatch match)
{
for (int i = 0; i < regExps.Length; i++)
{
int length = regExps[i].Match(buffer);
if (length > 0)
{
match.Update(length, patterns[i]);
}
}
}
/// <summary>
/// Checks if this NFA matches the specified input text. The
/// matching will be performed from position zero (0) in the
/// buffer. This method will not read any characters from the
/// stream, just peek ahead.
/// </summary>
/// <param name="buffer">The input buffer to check</param>
/// <param name="match">The token match to update</param>
/// <returns>The number of characters matched</returns>
/// <exception cref="System.IO.IOException">
/// If an I/O error occurred
/// </exception>
public int Match(ReaderBuffer buffer, TokenMatch match)
{
int length = 0;
int pos = 1;
int peekChar;
NFAState state;
// The first step of the match loop has been unrolled and
// optimized for performance below.
this.queue.Clear();
peekChar = buffer.Peek(0);
if (peekChar >= 0 && peekChar < 128)
{
state = this.initialChar[peekChar];
if (state != null)
{
this.queue.AddLast(state);
}
}
if (peekChar >= 0)
{
this.initial.MatchTransitions((char)peekChar, this.queue, true);
}
this.queue.MarkEnd();
peekChar = buffer.Peek(1);
// The remaining match loop processes all subsequent states
while (!this.queue.Empty)
{
if (this.queue.Marked)
{
pos++;
peekChar = buffer.Peek(pos);
this.queue.MarkEnd();
}
state = this.queue.RemoveFirst();
if (state.Value != null)
{
match.Update(pos, state.Value);
}
if (peekChar >= 0)
{
state.MatchTransitions((char)peekChar, this.queue, false);
}
}
return(length);
}
/// <summary>
/// Checks if the automaton matches an input stream. The
/// matching will be performed from a specified position. This
/// method will not read any characters from the stream, just
/// peek ahead. The comparison can be done either in
/// case-sensitive or case-insensitive mode.
/// </summary>
/// <param name="buffer">The buffer to read from</param>
/// <param name="caseInsensitive">The case-insensitive flag</param>
/// <returns>The match value, or null if no match found</returns>
/// <exception cref="System.IO.IOException">
/// If an I/O error occurred
/// </exception>
public TokenPattern Match(ReaderBuffer buffer, bool caseInsensitive)
{
TokenPattern result = null;
DFAState state;
int pos = 0;
int c;
c = buffer.Peek(0);
if (c < 0)
{
return(null);
}
if (caseInsensitive)
{
c = char.ToLower((char)c);
}
if (c < 128)
{
state = this.ascii[c];
if (state == null)
{
return(null);
}
else if (state.Value != null)
{
result = state.Value;
}
pos++;
}
else
{
state = this.nonAscii;
}
while ((c = buffer.Peek(pos)) >= 0)
{
state = state.Tree.Find((char)c, caseInsensitive);
if (state == null)
{
break;
}
else if (state.Value != null)
{
result = state.Value;
}
pos++;
}
return(result);
}
/**
* Checks if the start of the input stream matches this
* regular expression.
*
* @param buffer the input buffer to check
*
* @return the longest match found, or
* zero (0) if no match was found
*
* @throws IOException if an I/O error occurred
*/
public override int Match(ReaderBuffer buffer)
{
if (matcher == null)
{
matcher = regExp.Matcher(buffer);
}
else
{
matcher.Reset(buffer);
}
return(matcher.MatchFromBeginning() ? matcher.Length() : 0);
}
/// <summary>
/// Checks if the start of the input stream matches this
/// regular expression.
/// </summary>
/// <param name="buffer">The input buffer to check</param>
/// <returns>The longest match found, or 0 if none was found</returns>
/// <exception cref="IOException">If an I/O error occurred</exception>
public override int Match(ReaderBuffer buffer)
{
if (this.matcher == null)
{
this.matcher = this.regExp.Matcher(buffer);
}
else
{
this.matcher.Reset(buffer);
}
return(this.matcher.MatchFromBeginning() ? this.matcher.Length : 0);
}
/**
* Checks if the start of the input stream matches this
* regular expression.
*
* @param buffer the input buffer to check
*
* @return the longest match found, or
* zero (0) if no match was found
*
* @throws IOException if an I/O error occurred
*/
public override int Match(ReaderBuffer buffer)
{
Match m;
// Ugly hack since .NET doesn't have a flag for when the
// end of the input string was encountered...
buffer.Peek(1024 * 16);
// Also, there is no API to limit the search to the specified
// position, so we double-check the index afterwards instead.
m = reg.Match(buffer.ToString(), buffer.Position);
if (m.Success && m.Index == buffer.Position)
{
return(m.Length);
}
else
{
return(0);
}
}
/**
* Searches for matching token patterns at the start of the
* input stream. If a match is found, the token match object
* is updated.
*
* @param buffer the input buffer to check
* @param match the token match to update
*
* @throws IOException if an I/O error occurred
*/
public override void Match(ReaderBuffer buffer, TokenMatch match) {
for (int i = 0; i < regExps.Length; i++) {
int length = regExps[i].Match(buffer);
if (length > 0) {
match.Update(length, patterns[i]);
}
}
}
/**
* Resets the matcher for use with a new look-ahead character
* input stream. This will clear all flags and set the match
* length to a negative value.
*
* @param buffer the character input buffer
*
* @since 1.5
*/
public void Reset(ReaderBuffer buffer) {
this.buffer = buffer;
Reset();
}
/**
* Checks if this NFA matches the specified input text. The
* matching will be performed from position zero (0) in the
* buffer. This method will not read any characters from the
* stream, just peek ahead.
*
* @param buffer the input buffer to check
* @param match the token match to update
*
* @return the number of characters matched, or
* zero (0) if no match was found
*
* @throws IOException if an I/O error occurred
*/
public int Match(ReaderBuffer buffer, TokenMatch match)
{
int length = 0;
int pos = 1;
int peekChar;
NFAState state;
// The first step of the match loop has been unrolled and
// optimized for performance below.
this.queue.Clear();
peekChar = buffer.Peek(0);
if (0 <= peekChar && peekChar < 128) {
state = this.initialChar[peekChar];
if (state != null) {
this.queue.AddLast(state);
}
}
if (peekChar >= 0) {
this.initial.MatchTransitions((char) peekChar, this.queue, true);
}
this.queue.MarkEnd();
peekChar = buffer.Peek(1);
// The remaining match loop processes all subsequent states
while (!this.queue.Empty) {
if (this.queue.Marked) {
pos++;
peekChar = buffer.Peek(pos);
this.queue.MarkEnd();
}
state = this.queue.RemoveFirst();
if (state.value != null) {
match.Update(pos, state.value);
}
if (peekChar >= 0) {
state.MatchTransitions((char) peekChar, this.queue, false);
}
}
return length;
}
/**
* Checks if the start of the input stream matches this
* regular expression.
*
* @param buffer the input buffer to check
*
* @return the longest match found, or
* zero (0) if no match was found
*
* @throws IOException if an I/O error occurred
*/
public override int Match(ReaderBuffer buffer) {
Match m;
// Ugly hack since .NET doesn't have a flag for when the
// end of the input string was encountered...
buffer.Peek(1024 * 16);
// Also, there is no API to limit the search to the specified
// position, so we double-check the index afterwards instead.
m = reg.Match(buffer.ToString(), buffer.Position);
if (m.Success && m.Index == buffer.Position) {
return m.Length;
} else {
return 0;
}
}
/** * Checks if the start of the input stream matches this * regular expression. * * @param buffer the input buffer to check * * @return the longest match found, or * zero (0) if no match was found * * @throws IOException if an I/O error occurred */ public abstract int Match(ReaderBuffer buffer);
/**
* Searches for matching token patterns at the start of the
* input stream. If a match is found, the token match object
* is updated.
*
* @param buffer the input buffer to check
* @param match the token match to update
*
* @throws IOException if an I/O error occurred
*/
public override void Match(ReaderBuffer buffer, TokenMatch match)
{
automaton.Match(buffer, match);
}
/** * Searches for matching token patterns at the start of the * input stream. If a match is found, the token match object * is updated. * * @param buffer the input buffer to check * @param match the token match to update * * @throws IOException if an I/O error occurred */ public abstract void Match(ReaderBuffer buffer, TokenMatch match);
/**
* Finds all matches and adds the lengths to the matches set.
*
* @param m the matcher being used
* @param buffer the input character buffer to match
* @param start the starting position
* @param length the match length at the start position
* @param count the number of sub-elements matched
* @param attempt the number of match attempts here
*
* @throws IOException if an I/O error occurred
*/
private void FindMatches(Matcher m,
ReaderBuffer buffer,
int start,
int length,
int count,
int attempt)
{
int subLength;
// Check match ending here
if (count > max) {
return;
}
if (min <= count && attempt == 0) {
if (matches.Length <= length) {
matches.Length = length + 10;
}
matches[length] = true;
}
// Check element match
subLength = elem.Match(m, buffer, start, attempt);
if (subLength < 0) {
return;
} else if (subLength == 0) {
if (min == count + 1) {
if (matches.Length <= length) {
matches.Length = length + 10;
}
matches[length] = true;
}
return;
}
// Find alternative and subsequent matches
FindMatches(m, buffer, start, length, count, attempt + 1);
FindMatches(m,
buffer,
start + subLength,
length + subLength,
count + 1,
0);
}
/**
* Returns the length of a matching string starting at the
* specified position. The number of matches to skip can also be
* specified.
*
* @param m the matcher being used
* @param buffer the input character buffer to match
* @param start the starting position
* @param skip the number of matches to skip
*
* @return the length of the matching string, or
* -1 if no match was found
*
* @throws IOException if an I/O error occurred
*/
public override int Match(Matcher m,
ReaderBuffer buffer,
int start,
int skip)
{
if (skip == 0) {
matchStart = -1;
matches = null;
}
switch (type) {
case RepeatType.GREEDY:
return MatchGreedy(m, buffer, start, skip);
case RepeatType.RELUCTANT:
return MatchReluctant(m, buffer, start, skip);
case RepeatType.POSSESSIVE:
if (skip == 0) {
return MatchPossessive(m, buffer, start, 0);
}
break;
}
return -1;
}
/**
* Returns the length of a matching string starting at the
* specified position. The number of matches to skip can also be
* specified, but numbers higher than zero (0) cause a failed
* match for any element that doesn't attempt to combine other
* elements.
*
* @param m the matcher being used
* @param buffer the input character buffer to match
* @param start the starting position
* @param skip the number of matches to skip
*
* @return the length of the longest matching string, or
* -1 if no match was found
*
* @throws IOException if an I/O error occurred
*/
public override int Match(Matcher m,
ReaderBuffer buffer,
int start,
int skip) {
int length1 = -1;
int length2 = 0;
int skip1 = 0;
int skip2 = 0;
while (skip >= 0) {
length1 = elem1.Match(m, buffer, start, skip1);
if (length1 < 0) {
return -1;
}
length2 = elem2.Match(m, buffer, start + length1, skip2);
if (length2 < 0) {
skip1++;
skip2 = 0;
} else {
skip2++;
skip--;
}
}
return length1 + length2;
}
/** * Checks if the start of the input stream matches this * regular expression. * * @param buffer the input buffer to check * * @return the longest match found, or * zero (0) if no match was found * * @throws IOException if an I/O error occurred */ public abstract int Match(ReaderBuffer buffer);
/**
* Creates a new matcher for the specified look-ahead
* character input stream.
*
* @param buffer the character input buffer
*
* @return the regular expresion matcher
*
* @since 1.5
*/
public Matcher Matcher(ReaderBuffer buffer) {
return new Matcher((Element) element.Clone(), buffer, ignoreCase);
}
/**
* Searches for matching token patterns at the start of the
* input stream. If a match is found, the token match object
* is updated.
*
* @param buffer the input buffer to check
* @param match the token match to update
*
* @throws IOException if an I/O error occurred
*/
public override void Match(ReaderBuffer buffer, TokenMatch match) {
automaton.Match(buffer, match);
}
/**
* Searches for matching token patterns at the start of the
* input stream. If a match is found, the token match object
* is updated.
*
* @param buffer the input buffer to check
* @param match the token match to update
*
* @throws IOException if an I/O error occurred
*/
public override void Match(ReaderBuffer buffer, TokenMatch match) {
TokenPattern res = automaton.Match(buffer, ignoreCase);
if (res != null) {
match.Update(res.Pattern.Length, res);
}
}
/**
* Checks if the automaton matches an input stream. The
* matching will be performed from a specified position. This
* method will not read any characters from the stream, just
* peek ahead. The comparison can be done either in
* case-sensitive or case-insensitive mode.
*
* @param input the input stream to check
* @param pos the starting position
* @param caseInsensitive the case-insensitive flag
*
* @return the match value, or
* null if no match was found
*
* @throws IOException if an I/O error occurred
*/
public TokenPattern Match(ReaderBuffer buffer, bool caseInsensitive) {
TokenPattern result = null;
DFAState state;
int pos = 0;
int c;
c = buffer.Peek(0);
if (c < 0) {
return null;
}
if (caseInsensitive) {
c = Char.ToLower((char) c);
}
if (c < 128) {
state = ascii[c];
if (state == null) {
return null;
} else if (state.value != null) {
result = state.value;
}
pos++;
} else {
state = nonAscii;
}
while ((c = buffer.Peek(pos)) >= 0) {
state = state.tree.Find((char) c, caseInsensitive);
if (state == null) {
break;
} else if (state.value != null) {
result = state.value;
}
pos++;
}
return result;
}
/** * Searches for matching token patterns at the start of the * input stream. If a match is found, the token match object * is updated. * * @param buffer the input buffer to check * @param match the token match to update * * @throws IOException if an I/O error occurred */ public abstract void Match(ReaderBuffer buffer, TokenMatch match);
/**
* Creates a new tokenizer for the specified input stream. The
* tokenizer can be set to process tokens either in
* case-sensitive or case-insensitive mode.
*
* @param input the input stream to read
* @param ignoreCase the character case ignore flag
*
* @since 1.5
*/
public Tokenizer(TextReader input, bool ignoreCase) {
this.stringDfaMatcher = new StringDFAMatcher(ignoreCase);
this.nfaMatcher = new NFAMatcher(ignoreCase);
this.regExpMatcher = new RegExpMatcher(ignoreCase);
this.buffer = new ReaderBuffer(input);
}
/**
* Resets this tokenizer for usage with another input stream.
* This method will clear all the internal state in the
* tokenizer as well as close the previous input stream. It
* is normally called in order to reuse a parser and
* tokenizer pair with multiple input streams, thereby
* avoiding the cost of re-analyzing the grammar structures.
*
* @param input the new input stream to read
*
* @see Parser#reset(Reader)
*
* @since 1.5
*/
public void Reset(TextReader input) {
this.buffer.Dispose();
this.buffer = new ReaderBuffer(input);
this.previousToken = null;
this.lastMatch.Clear();
}
/**
* Returns the length of a matching string starting at the
* specified position. The number of matches to skip can also
* be specified, but numbers higher than zero (0) cause a
* failed match for any element that doesn't attempt to
* combine other elements.
*
* @param m the matcher being used
* @param buffer the input character buffer to match
* @param start the starting position
* @param skip the number of matches to skip
*
* @return the length of the matching string, or
* -1 if no match was found
*
* @throws IOException if an I/O error occurred
*/
public abstract int Match(Matcher m,
ReaderBuffer buffer,
int start,
int skip);
/**
* Returns the length of the longest possible matching string
* starting at the specified position. The number of matches
* to skip can also be specified.
*
* @param m the matcher being used
* @param buffer the input character buffer to match
* @param start the starting position
* @param skip the number of matches to skip
*
* @return the length of the longest matching string, or
* -1 if no match was found
*
* @throws IOException if an I/O error occurred
*/
private int MatchGreedy(Matcher m,
ReaderBuffer buffer,
int start,
int skip)
{
// Check for simple case
if (skip == 0) {
return MatchPossessive(m, buffer, start, 0);
}
// Find all matches
if (matchStart != start) {
matchStart = start;
matches = new BitArray(10);
FindMatches(m, buffer, start, 0, 0, 0);
}
// Find first non-skipped match
for (int i = matches.Count - 1; i >= 0; i--) {
if (matches[i]) {
if (skip == 0) {
return i;
}
skip--;
}
}
return -1;
}
/**
* Checks if the start of the input stream matches this
* regular expression.
*
* @param buffer the input buffer to check
*
* @return the longest match found, or
* zero (0) if no match was found
*
* @throws IOException if an I/O error occurred
*/
public override int Match(ReaderBuffer buffer) {
if (matcher == null) {
matcher = regExp.Matcher(buffer);
} else {
matcher.Reset(buffer);
}
return matcher.MatchFromBeginning() ? matcher.Length() : 0;
}
/**
* Returns the length of a matching string starting at the
* specified position. The number of matches to skip can also
* be specified, but numbers higher than zero (0) cause a
* failed match for any element that doesn't attempt to
* combine other elements.
*
* @param m the matcher being used
* @param buffer the input character buffer to match
* @param start the starting position
* @param skip the number of matches to skip
*
* @return the length of the longest matching string, or
* -1 if no match was found
*
* @throws IOException if an I/O error occurred
*/
public override int Match(Matcher m,
ReaderBuffer buffer,
int start,
int skip) {
int c;
if (skip != 0) {
return -1;
}
for (int i = 0; i < value.Length; i++) {
c = buffer.Peek(start + i);
if (c < 0) {
m.SetReadEndOfString();
return -1;
}
if (m.IsCaseInsensitive()) {
c = (int) Char.ToLower((char) c);
}
if (c != (int) value[i]) {
return -1;
}
}
return value.Length;
}
/**
* Returns the length of the maximum number of elements matching
* the string starting at the specified position. This method
* allows no backtracking, i.e. no skips..
*
* @param m the matcher being used
* @param buffer the input character buffer to match
* @param start the starting position
* @param count the start count, normally zero (0)
*
* @return the length of the longest matching string, or
* -1 if no match was found
*
* @throws IOException if an I/O error occurred
*/
private int MatchPossessive(Matcher m,
ReaderBuffer buffer,
int start,
int count)
{
int length = 0;
int subLength = 1;
// Match as many elements as possible
while (subLength > 0 && count < max) {
subLength = elem.Match(m, buffer, start + length, 0);
if (subLength >= 0) {
count++;
length += subLength;
}
}
// Return result
if (min <= count && count <= max) {
return length;
} else {
return -1;
}
}
/**
* Returns the length of a matching string starting at the
* specified position. The number of matches to skip can also be
* specified, but numbers higher than zero (0) cause a failed
* match for any element that doesn't attempt to combine other
* elements.
*
* @param m the matcher being used
* @param buffer the input character buffer to match
* @param start the starting position
* @param skip the number of matches to skip
*
* @return the length of the matching string, or
* -1 if no match was found
*
* @throws IOException if an I/O error occurred
*/
public override int Match(Matcher m,
ReaderBuffer buffer,
int start,
int skip) {
int c;
if (skip != 0) {
return -1;
}
c = buffer.Peek(start);
if (c < 0) {
m.SetReadEndOfString();
return -1;
}
if (m.IsCaseInsensitive()) {
c = (int) Char.ToLower((char) c);
}
return InSet((char) c) ? 1 : -1;
}
/**
* Returns the length of the shortest possible matching string
* starting at the specified position. The number of matches to
* skip can also be specified.
*
* @param m the matcher being used
* @param buffer the input character buffer to match
* @param start the starting position
* @param skip the number of matches to skip
*
* @return the length of the shortest matching string, or
* -1 if no match was found
*
* @throws IOException if an I/O error occurred
*/
private int MatchReluctant(Matcher m,
ReaderBuffer buffer,
int start,
int skip)
{
// Find all matches
if (matchStart != start) {
matchStart = start;
matches = new BitArray(10);
FindMatches(m, buffer, start, 0, 0, 0);
}
// Find first non-skipped match
for (int i = 0; i < matches.Count; i++) {
if (matches[i]) {
if (skip == 0) {
return i;
}
skip--;
}
}
return -1;
}