/*
* Svjatoslav Commons - shared library of common functionality.
- * Copyright ©2012-2014, Svjatoslav Agejenko, svjatoslav@svjatoslav.eu
+ * Copyright ©2012-2017, Svjatoslav Agejenko, svjatoslav@svjatoslav.eu
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 3 of the GNU Lesser General Public License
import java.util.List;
import java.util.Stack;
+import static eu.svjatoslav.commons.string.tokenizer.Terminator.TerminationStrategy.DROP;
+
public class Tokenizer {
- private final List<Terminator> terminators = new ArrayList<Terminator>();
- private final String source;
-
- Stack<Integer> tokenIndexes = new Stack<Integer>();
-
- private int currentIndex = 0;
-
- public Tokenizer(final String source) {
- this.source = source;
- }
-
- public void addTerminator(final String startSequence,
- final boolean ignoreTerminator) {
- terminators.add(new Terminator(startSequence, ignoreTerminator));
- }
-
- public void addTerminator(final String startSequence,
- final String endSequence, final boolean ignoreTerminator) {
- terminators.add(new Terminator(startSequence, endSequence,
- ignoreTerminator));
- }
-
- public void expectNextToken(final String value)
- throws InvalidSyntaxException {
- final TokenizerMatch match = getNextToken();
- if (!value.equals(match.token))
- throw new InvalidSyntaxException("Expected \"" + value
- + "\" but got \"" + match.token + "\" instead.");
- }
-
- public TokenizerMatch getNextToken() {
- tokenIndexes.push(currentIndex);
- final StringBuffer result = new StringBuffer();
-
- while (true) {
- if (currentIndex >= source.length())
- return null;
-
- boolean accumulateCurrentChar = true;
-
- findTerminator: for (final Terminator terminator : terminators)
- if (sequenceMatches(terminator.startSequence))
-
- if (terminator.ignoreTerminator) {
- currentIndex += terminator.startSequence.length();
-
- if (terminator.endSequence != null)
- skipUntilSequence(terminator.endSequence);
-
- if (result.length() > 0)
- return new TokenizerMatch(result.toString(),
- terminator);
- else {
- accumulateCurrentChar = false;
- break findTerminator;
- }
- } else if (result.length() > 0)
- return new TokenizerMatch(result.toString(), terminator);
- else {
- currentIndex += terminator.startSequence.length();
- return new TokenizerMatch(terminator.startSequence,
- terminator);
- }
-
- if (accumulateCurrentChar) {
- result.append(source.charAt(currentIndex));
- currentIndex++;
- }
- }
-
- }
-
- public boolean probeNextToken(final String token) {
- if (token.equals(getNextToken().token))
- return true;
-
- unreadToken();
- return false;
- }
-
- public boolean sequenceMatches(final String sequence) {
- if ((currentIndex + sequence.length()) > source.length())
- return false;
-
- for (int i = 0; i < sequence.length(); i++)
- if (sequence.charAt(i) != source.charAt(i + currentIndex))
- return false;
-
- return true;
- }
-
- public void skipUntilDataEnd() {
- tokenIndexes.push(currentIndex);
- currentIndex = source.length();
- }
-
- public void skipUntilSequence(final String sequence) {
- while (currentIndex < source.length()) {
- if (sequenceMatches(sequence)) {
- currentIndex += sequence.length();
- return;
- }
-
- currentIndex++;
- }
- }
-
- public void unreadToken() {
- currentIndex = tokenIndexes.pop();
- }
+ final Stack<Integer> tokenIndexes = new Stack<>();
+ private final List<Terminator> terminators = new ArrayList<>();
+ private String source;
+ private int currentIndex = 0;
+
+ public Tokenizer(final String source) {
+ this.source = source;
+ }
+
+ public Tokenizer(){}
+
+ public Tokenizer setSource(String source){
+ this.source = source;
+ currentIndex = 0;
+ return this;
+ }
+
+ public Tokenizer addTerminator(final String startSequence,
+ final Terminator.TerminationStrategy terminationStrategy) {
+ terminators.add(new Terminator(startSequence, terminationStrategy));
+ return this;
+ }
+
+ public Tokenizer addTerminator(final String startSequence,
+ final String endSequence, final Terminator.TerminationStrategy terminationStrategy) {
+ terminators.add(new Terminator(startSequence, endSequence, terminationStrategy));
+ return this;
+ }
+
+ public void expectAndConsumeNextToken(final String value)
+ throws InvalidSyntaxException {
+ final TokenizerMatch match = getNextToken();
+ if (!value.equals(match.token))
+ throw new InvalidSyntaxException("Expected \"" + value
+ + "\" but got \"" + match.token + "\" instead.");
+ }
+
+ public TokenizerMatch getNextToken() {
+ tokenIndexes.push(currentIndex);
+ final StringBuilder result = new StringBuilder();
+
+ while (true) {
+ if (currentIndex >= source.length())
+ return null;
+
+ boolean accumulateCurrentChar = true;
+
+ for (final Terminator terminator : terminators)
+ if (sequenceMatches(terminator.startSequence))
+
+ if (terminator.termination == DROP) {
+ currentIndex += terminator.startSequence.length();
+
+ if (terminator.endSequence != null)
+ skipUntilSequence(terminator.endSequence);
+
+ if (result.length() > 0)
+ return new TokenizerMatch(result.toString(),
+ terminator);
+ else {
+ accumulateCurrentChar = false;
+ break;
+ }
+ } else if (result.length() > 0)
+ return new TokenizerMatch(result.toString(), terminator);
+ else {
+ currentIndex += terminator.startSequence.length();
+ return new TokenizerMatch(terminator.startSequence,
+ terminator);
+ }
+
+ if (accumulateCurrentChar) {
+ result.append(source.charAt(currentIndex));
+ currentIndex++;
+ }
+ }
+
+ }
+
+ public boolean consumeIfNextToken(final String token) {
+ if (token.equals(getNextToken().token))
+ return true;
+
+ unreadToken();
+ return false;
+ }
+
+ public TokenizerMatch peekNextToken(){
+ TokenizerMatch result = getNextToken();
+ unreadToken();
+ return result;
+ }
+
+ public boolean peekIsOneOf(String ... possibilities){
+ String nextToken = peekNextToken().token;
+
+ for (String possibility : possibilities)
+ if (possibility.equals(nextToken))
+ return true;
+
+ return false;
+ }
+
+ public void peekExpectNoneOf(String ... possibilities) throws InvalidSyntaxException {
+ TokenizerMatch nextToken = peekNextToken();
+
+ for (String possibility : possibilities)
+ if (possibility.equals(nextToken))
+ throw new InvalidSyntaxException("Not expected \"" + nextToken + "\" here.");
+ }
+
+
+ public boolean sequenceMatches(final String sequence) {
+ if ((currentIndex + sequence.length()) > source.length())
+ return false;
+
+ for (int i = 0; i < sequence.length(); i++)
+ if (sequence.charAt(i) != source.charAt(i + currentIndex))
+ return false;
+
+ return true;
+ }
+
+ public void skipUntilDataEnd() {
+ tokenIndexes.push(currentIndex);
+ currentIndex = source.length();
+ }
+
+ public void skipUntilSequence(final String sequence) {
+ while (currentIndex < source.length()) {
+ if (sequenceMatches(sequence)) {
+ currentIndex += sequence.length();
+ return;
+ }
+
+ currentIndex++;
+ }
+ }
+
+ public void unreadToken() {
+ currentIndex = tokenIndexes.pop();
+ }
}