2 * Svjatoslav Commons - shared library of common functionality.
3 * Copyright ©2012-2017, 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 final Stack<Integer> tokenIndexes = new Stack<>();
19 private final List<Terminator> terminators = new ArrayList<>();
20 private final String source;
21 private int currentIndex = 0;
23 public Tokenizer(final String source) {
27 public void addTerminator(final String startSequence,
28 final boolean ignoreTerminator) {
29 terminators.add(new Terminator(startSequence, ignoreTerminator));
32 public void addTerminator(final String startSequence,
33 final String endSequence, final boolean ignoreTerminator) {
34 terminators.add(new Terminator(startSequence, endSequence,
38 public void expectNextToken(final String value)
39 throws InvalidSyntaxException {
40 final TokenizerMatch match = getNextToken();
41 if (!value.equals(match.token))
42 throw new InvalidSyntaxException("Expected \"" + value
43 + "\" but got \"" + match.token + "\" instead.");
46 public TokenizerMatch getNextToken() {
47 tokenIndexes.push(currentIndex);
48 final StringBuilder result = new StringBuilder();
51 if (currentIndex >= source.length())
54 boolean accumulateCurrentChar = true;
56 for (final Terminator terminator : terminators)
57 if (sequenceMatches(terminator.startSequence))
59 if (terminator.ignoreTerminator) {
60 currentIndex += terminator.startSequence.length();
62 if (terminator.endSequence != null)
63 skipUntilSequence(terminator.endSequence);
65 if (result.length() > 0)
66 return new TokenizerMatch(result.toString(),
69 accumulateCurrentChar = false;
72 } else if (result.length() > 0)
73 return new TokenizerMatch(result.toString(), terminator);
75 currentIndex += terminator.startSequence.length();
76 return new TokenizerMatch(terminator.startSequence,
80 if (accumulateCurrentChar) {
81 result.append(source.charAt(currentIndex));
88 public boolean probeNextToken(final String token) {
89 if (token.equals(getNextToken().token))
96 public boolean sequenceMatches(final String sequence) {
97 if ((currentIndex + sequence.length()) > source.length())
100 for (int i = 0; i < sequence.length(); i++)
101 if (sequence.charAt(i) != source.charAt(i + currentIndex))
107 public void skipUntilDataEnd() {
108 tokenIndexes.push(currentIndex);
109 currentIndex = source.length();
112 public void skipUntilSequence(final String sequence) {
113 while (currentIndex < source.length()) {
114 if (sequenceMatches(sequence)) {
115 currentIndex += sequence.length();
123 public void unreadToken() {
124 currentIndex = tokenIndexes.pop();