2 * Svjatoslav Commons - shared library of common functionality.
3 * Copyright ©2012-2014, Svjatoslav Agejenko, svjatoslav@svjatoslav.eu
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of version 3 of the GNU Lesser General Public License
7 * or later as published by the Free Software Foundation.
10 package eu.svjatoslav.commons.string.tokenizer;
12 import java.util.ArrayList;
13 import java.util.List;
14 import java.util.Stack;
16 public class Tokenizer {
18 private final List<Terminator> terminators = new ArrayList<Terminator>();
19 private final String source;
21 Stack<Integer> tokenIndexes = new Stack<Integer>();
23 private int currentIndex = 0;
25 public Tokenizer(final String source) {
29 public void addTerminator(final String startSequence,
30 final boolean ignoreTerminator) {
31 terminators.add(new Terminator(startSequence, ignoreTerminator));
34 public void addTerminator(final String startSequence,
35 final String endSequence, final boolean ignoreTerminator) {
36 terminators.add(new Terminator(startSequence, endSequence,
40 public void expectNextToken(final String value)
41 throws InvalidSyntaxException {
42 final TokenizerMatch match = getNextToken();
43 if (!value.equals(match.token))
44 throw new InvalidSyntaxException("Expected \"" + value
45 + "\" but got \"" + match.token + "\" instead.");
48 public TokenizerMatch getNextToken() {
49 tokenIndexes.push(currentIndex);
50 final StringBuffer result = new StringBuffer();
53 if (currentIndex >= source.length())
56 boolean accumulateCurrentChar = true;
58 findTerminator: for (final Terminator terminator : terminators)
59 if (sequenceMatches(terminator.startSequence))
61 if (terminator.ignoreTerminator) {
62 currentIndex += terminator.startSequence.length();
64 if (terminator.endSequence != null)
65 skipUntilSequence(terminator.endSequence);
67 if (result.length() > 0)
68 return new TokenizerMatch(result.toString(),
71 accumulateCurrentChar = false;
74 } else if (result.length() > 0)
75 return new TokenizerMatch(result.toString(), terminator);
77 currentIndex += terminator.startSequence.length();
78 return new TokenizerMatch(terminator.startSequence,
82 if (accumulateCurrentChar) {
83 result.append(source.charAt(currentIndex));
90 public boolean probeNextToken(final String token) {
91 if (token.equals(getNextToken().token))
98 public boolean sequenceMatches(final String sequence) {
99 if ((currentIndex + sequence.length()) > source.length())
102 for (int i = 0; i < sequence.length(); i++)
103 if (sequence.charAt(i) != source.charAt(i + currentIndex))
109 public void skipUntilDataEnd() {
110 tokenIndexes.push(currentIndex);
111 currentIndex = source.length();
114 public void skipUntilSequence(final String sequence) {
115 while (currentIndex < source.length()) {
116 if (sequenceMatches(sequence)) {
117 currentIndex += sequence.length();
125 public void unreadToken() {
126 currentIndex = tokenIndexes.pop();