Examples with TokenStream org.apache.lucene.analysis.TokenStream used on opensource projects

Example 56 with TokenStream

use of org.apache.lucene.analysis.TokenStream in project lucene-solr by apache.

the class FuzzySuggesterTest method testGraphDups.

public void testGraphDups() throws Exception {
    final Analyzer analyzer = new Analyzer() {

        @Override
        protected TokenStreamComponents createComponents(String fieldName) {
            Tokenizer tokenizer = new MockTokenizer(MockTokenizer.SIMPLE, true);
            return new TokenStreamComponents(tokenizer) {

                int tokenStreamCounter = 0;

                final TokenStream[] tokenStreams = new TokenStream[] { new CannedTokenStream(new Token[] { token("wifi", 1, 1), token("hotspot", 0, 2), token("network", 1, 1), token("is", 1, 1), token("slow", 1, 1) }), new CannedTokenStream(new Token[] { token("wi", 1, 1), token("hotspot", 0, 3), token("fi", 1, 1), token("network", 1, 1), token("is", 1, 1), token("fast", 1, 1) }), new CannedTokenStream(new Token[] { token("wifi", 1, 1), token("hotspot", 0, 2), token("network", 1, 1) }) };

                @Override
                public TokenStream getTokenStream() {
                    TokenStream result = tokenStreams[tokenStreamCounter];
                    tokenStreamCounter++;
                    return result;
                }

                @Override
                protected void setReader(final Reader reader) {
                }
            };
        }
    };
    Input[] keys = new Input[] { new Input("wifi network is slow", 50), new Input("wi fi network is fast", 10) };
    Directory tempDir = getDirectory();
    FuzzySuggester suggester = new FuzzySuggester(tempDir, "fuzzy", analyzer);
    suggester.build(new InputArrayIterator(keys));
    List<LookupResult> results = suggester.lookup("wifi network", false, 10);
    if (VERBOSE) {
        System.out.println("Results: " + results);
    }
    assertEquals(2, results.size());
    assertEquals("wifi network is slow", results.get(0).key);
    assertEquals(50, results.get(0).value);
    assertEquals("wi fi network is fast", results.get(1).key);
    assertEquals(10, results.get(1).value);
    IOUtils.close(tempDir, analyzer);
}

Example 57 with TokenStream

use of org.apache.lucene.analysis.TokenStream in project lucene-solr by apache.

the class TestReversedWildcardFilterFactory method testIndexingAnalysis.

@Test
public void testIndexingAnalysis() throws Exception {
    Analyzer a = schema.getIndexAnalyzer();
    String text = "one two three si𝄞x";
    // field one
    TokenStream input = a.tokenStream("one", text);
    assertTokenStreamContents(input, new String[] { "
eno", "one", "
owt", "two", "
eerht", "three", "
x𝄞is", "si𝄞x" }, new int[] { 0, 0, 4, 4, 8, 8, 14, 14 }, new int[] { 3, 3, 7, 7, 13, 13, 19, 19 }, new int[] { 1, 0, 1, 0, 1, 0, 1, 0 });
    // field two
    input = a.tokenStream("two", text);
    assertTokenStreamContents(input, new String[] { "
eno", "
owt", "
eerht", "
x𝄞is" }, new int[] { 0, 4, 8, 14 }, new int[] { 3, 7, 13, 19 }, new int[] { 1, 1, 1, 1 });
    // field three
    input = a.tokenStream("three", text);
    assertTokenStreamContents(input, new String[] { "one", "two", "three", "si𝄞x" }, new int[] { 0, 4, 8, 14 }, new int[] { 3, 7, 13, 19 });
}

Example 58 with TokenStream

use of org.apache.lucene.analysis.TokenStream in project lucene-solr by apache.

the class TestReversedWildcardFilterFactory method testReversedTokens.

@Test
public void testReversedTokens() throws IOException {
    String text = "simple text";
    args.put("withOriginal", "true");
    ReversedWildcardFilterFactory factory = new ReversedWildcardFilterFactory(args);
    TokenStream input = factory.create(whitespaceMockTokenizer(text));
    assertTokenStreamContents(input, new String[] { "
elpmis", "simple", "
txet", "text" }, new int[] { 1, 0, 1, 0 });
    // now without original tokens
    args.put("withOriginal", "false");
    factory = new ReversedWildcardFilterFactory(args);
    input = factory.create(whitespaceMockTokenizer(text));
    assertTokenStreamContents(input, new String[] { "
elpmis", "
txet" }, new int[] { 1, 1 });
}

Example 59 with TokenStream

use of org.apache.lucene.analysis.TokenStream in project lucene-solr by apache.

the class MoreLikeThis method addTermFrequencies.

/**
   * Adds term frequencies found by tokenizing text from reader into the Map words
   *
   * @param r a source of text to be tokenized
   * @param perFieldTermFrequencies a Map of terms and their frequencies per field
   * @param fieldName Used by analyzer for any special per-field analysis
   */
private void addTermFrequencies(Reader r, Map<String, Map<String, Int>> perFieldTermFrequencies, String fieldName) throws IOException {
    if (analyzer == null) {
        throw new UnsupportedOperationException("To use MoreLikeThis without " + "term vectors, you must provide an Analyzer");
    }
    Map<String, Int> termFreqMap = perFieldTermFrequencies.get(fieldName);
    if (termFreqMap == null) {
        termFreqMap = new HashMap<>();
        perFieldTermFrequencies.put(fieldName, termFreqMap);
    }
    try (TokenStream ts = analyzer.tokenStream(fieldName, r)) {
        int tokenCount = 0;
        // for every token
        CharTermAttribute termAtt = ts.addAttribute(CharTermAttribute.class);
        ts.reset();
        while (ts.incrementToken()) {
            String word = termAtt.toString();
            tokenCount++;
            if (tokenCount > maxNumTokensParsed) {
                break;
            }
            if (isNoiseWord(word)) {
                continue;
            }
            // increment frequency
            Int cnt = termFreqMap.get(word);
            if (cnt == null) {
                termFreqMap.put(word, new Int());
            } else {
                cnt.x++;
            }
        }
        ts.end();
    }
}

Example 60 with TokenStream

use of org.apache.lucene.analysis.TokenStream in project lucene-solr by apache.

the class FreeTextSuggester method lookup.

/** Retrieve suggestions. */
public List<LookupResult> lookup(final CharSequence key, Set<BytesRef> contexts, int num) throws IOException {
    if (contexts != null) {
        throw new IllegalArgumentException("this suggester doesn't support contexts");
    }
    if (fst == null) {
        throw new IllegalStateException("Lookup not supported at this time");
    }
    try (TokenStream ts = queryAnalyzer.tokenStream("", key.toString())) {
        TermToBytesRefAttribute termBytesAtt = ts.addAttribute(TermToBytesRefAttribute.class);
        OffsetAttribute offsetAtt = ts.addAttribute(OffsetAttribute.class);
        PositionLengthAttribute posLenAtt = ts.addAttribute(PositionLengthAttribute.class);
        PositionIncrementAttribute posIncAtt = ts.addAttribute(PositionIncrementAttribute.class);
        ts.reset();
        BytesRefBuilder[] lastTokens = new BytesRefBuilder[grams];
        //System.out.println("lookup: key='" + key + "'");
        // Run full analysis, but save only the
        // last 1gram, last 2gram, etc.:
        int maxEndOffset = -1;
        boolean sawRealToken = false;
        while (ts.incrementToken()) {
            BytesRef tokenBytes = termBytesAtt.getBytesRef();
            sawRealToken |= tokenBytes.length > 0;
            // TODO: this is somewhat iffy; today, ShingleFilter
            // sets posLen to the gram count; maybe we should make
            // a separate dedicated att for this?
            int gramCount = posLenAtt.getPositionLength();
            assert gramCount <= grams;
            // Safety: make sure the recalculated count "agrees":
            if (countGrams(tokenBytes) != gramCount) {
                throw new IllegalArgumentException("tokens must not contain separator byte; got token=" + tokenBytes + " but gramCount=" + gramCount + " does not match recalculated count=" + countGrams(tokenBytes));
            }
            maxEndOffset = Math.max(maxEndOffset, offsetAtt.endOffset());
            BytesRefBuilder b = new BytesRefBuilder();
            b.append(tokenBytes);
            lastTokens[gramCount - 1] = b;
        }
        ts.end();
        if (!sawRealToken) {
            throw new IllegalArgumentException("no tokens produced by analyzer, or the only tokens were empty strings");
        }
        // Carefully fill last tokens with _ tokens;
        // ShingleFilter appraently won't emit "only hole"
        // tokens:
        int endPosInc = posIncAtt.getPositionIncrement();
        // Note this will also be true if input is the empty
        // string (in which case we saw no tokens and
        // maxEndOffset is still -1), which in fact works out OK
        // because we fill the unigram with an empty BytesRef
        // below:
        boolean lastTokenEnded = offsetAtt.endOffset() > maxEndOffset || endPosInc > 0;
        if (lastTokenEnded) {
            // starting with "foo":
            for (int i = grams - 1; i > 0; i--) {
                BytesRefBuilder token = lastTokens[i - 1];
                if (token == null) {
                    continue;
                }
                token.append(separator);
                lastTokens[i] = token;
            }
            lastTokens[0] = new BytesRefBuilder();
        }
        Arc<Long> arc = new Arc<>();
        BytesReader bytesReader = fst.getBytesReader();
        // Try highest order models first, and if they return
        // results, return that; else, fallback:
        double backoff = 1.0;
        List<LookupResult> results = new ArrayList<>(num);
        // We only add a given suffix once, from the highest
        // order model that saw it; for subsequent lower order
        // models we skip it:
        final Set<BytesRef> seen = new HashSet<>();
        for (int gram = grams - 1; gram >= 0; gram--) {
            BytesRefBuilder token = lastTokens[gram];
            // Don't make unigram predictions from empty string:
            if (token == null || (token.length() == 0 && key.length() > 0)) {
                //System.out.println("  gram=" + gram + ": skip: not enough input");
                continue;
            }
            if (endPosInc > 0 && gram <= endPosInc) {
                //System.out.println("  break: only holes now");
                break;
            }
            //System.out.println("try " + (gram+1) + " gram token=" + token.utf8ToString());
            // TODO: we could add fuzziness here
            // match the prefix portion exactly
            //Pair<Long,BytesRef> prefixOutput = null;
            Long prefixOutput = null;
            try {
                prefixOutput = lookupPrefix(fst, bytesReader, token.get(), arc);
            } catch (IOException bogus) {
                throw new RuntimeException(bogus);
            }
            if (prefixOutput == null) {
                // This model never saw this prefix, e.g. the
                // trigram model never saw context "purple mushroom"
                backoff *= ALPHA;
                continue;
            }
            // TODO: we could do this division at build time, and
            // bake it into the FST?
            // Denominator for computing scores from current
            // model's predictions:
            long contextCount = totTokens;
            BytesRef lastTokenFragment = null;
            for (int i = token.length() - 1; i >= 0; i--) {
                if (token.byteAt(i) == separator) {
                    BytesRef context = new BytesRef(token.bytes(), 0, i);
                    Long output = Util.get(fst, Util.toIntsRef(context, new IntsRefBuilder()));
                    assert output != null;
                    contextCount = decodeWeight(output);
                    lastTokenFragment = new BytesRef(token.bytes(), i + 1, token.length() - i - 1);
                    break;
                }
            }
            final BytesRefBuilder finalLastToken = new BytesRefBuilder();
            if (lastTokenFragment == null) {
                finalLastToken.copyBytes(token.get());
            } else {
                finalLastToken.copyBytes(lastTokenFragment);
            }
            CharsRefBuilder spare = new CharsRefBuilder();
            // complete top-N
            TopResults<Long> completions = null;
            try {
                // Because we store multiple models in one FST
                // (1gram, 2gram, 3gram), we must restrict the
                // search so that it only considers the current
                // model.  For highest order model, this is not
                // necessary since all completions in the FST
                // must be from this model, but for lower order
                // models we have to filter out the higher order
                // ones:
                // Must do num+seen.size() for queue depth because we may
                // reject up to seen.size() paths in acceptResult():
                Util.TopNSearcher<Long> searcher = new Util.TopNSearcher<Long>(fst, num, num + seen.size(), weightComparator) {

                    BytesRefBuilder scratchBytes = new BytesRefBuilder();

                    @Override
                    protected void addIfCompetitive(Util.FSTPath<Long> path) {
                        if (path.arc.label != separator) {
                            //System.out.println("    keep path: " + Util.toBytesRef(path.input, new BytesRef()).utf8ToString() + "; " + path + "; arc=" + path.arc);
                            super.addIfCompetitive(path);
                        } else {
                        //System.out.println("    prevent path: " + Util.toBytesRef(path.input, new BytesRef()).utf8ToString() + "; " + path + "; arc=" + path.arc);
                        }
                    }

                    @Override
                    protected boolean acceptResult(IntsRef input, Long output) {
                        Util.toBytesRef(input, scratchBytes);
                        finalLastToken.grow(finalLastToken.length() + scratchBytes.length());
                        int lenSav = finalLastToken.length();
                        finalLastToken.append(scratchBytes);
                        //System.out.println("    accept? input='" + scratchBytes.utf8ToString() + "'; lastToken='" + finalLastToken.utf8ToString() + "'; return " + (seen.contains(finalLastToken) == false));
                        boolean ret = seen.contains(finalLastToken.get()) == false;
                        finalLastToken.setLength(lenSav);
                        return ret;
                    }
                };
                // since this search is initialized with a single start node 
                // it is okay to start with an empty input path here
                searcher.addStartPaths(arc, prefixOutput, true, new IntsRefBuilder());
                completions = searcher.search();
                assert completions.isComplete;
            } catch (IOException bogus) {
                throw new RuntimeException(bogus);
            }
            int prefixLength = token.length();
            BytesRefBuilder suffix = new BytesRefBuilder();
            nextCompletion: for (Result<Long> completion : completions) {
                token.setLength(prefixLength);
                // append suffix
                Util.toBytesRef(completion.input, suffix);
                token.append(suffix);
                //System.out.println("    completion " + token.utf8ToString());
                // Skip this path if a higher-order model already
                // saw/predicted its last token:
                BytesRef lastToken = token.get();
                for (int i = token.length() - 1; i >= 0; i--) {
                    if (token.byteAt(i) == separator) {
                        assert token.length() - i - 1 > 0;
                        lastToken = new BytesRef(token.bytes(), i + 1, token.length() - i - 1);
                        break;
                    }
                }
                if (seen.contains(lastToken)) {
                    //System.out.println("      skip dup " + lastToken.utf8ToString());
                    continue nextCompletion;
                }
                seen.add(BytesRef.deepCopyOf(lastToken));
                spare.copyUTF8Bytes(token.get());
                LookupResult result = new LookupResult(spare.toString(), (long) (Long.MAX_VALUE * backoff * ((double) decodeWeight(completion.output)) / contextCount));
                results.add(result);
                assert results.size() == seen.size();
            //System.out.println("  add result=" + result);
            }
            backoff *= ALPHA;
        }
        Collections.sort(results, new Comparator<LookupResult>() {

            @Override
            public int compare(LookupResult a, LookupResult b) {
                if (a.value > b.value) {
                    return -1;
                } else if (a.value < b.value) {
                    return 1;
                } else {
                    // Tie break by UTF16 sort order:
                    return ((String) a.key).compareTo((String) b.key);
                }
            }
        });
        if (results.size() > num) {
            results.subList(num, results.size()).clear();
        }
        return results;
    }
}