org.apache.lucene.index.SegmentReadState#org.apache.lucene.codecs.FieldsProducer源码实例Demo

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  FieldsProducer postings = PostingsFormat.forName("Lucene84").fieldsProducer(state);
  if (state.context.context != IOContext.Context.MERGE) {
    FieldsProducer loadedPostings;
    try {
      postings.checkIntegrity();
      loadedPostings = new DirectFields(state, postings, minSkipCount, lowFreqCutoff);
    } finally {
      postings.close();
    }
    return loadedPostings;
  } else {
    // Don't load postings for merge:
    return postings;
  }
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState readState)
  throws IOException {

  // Load our ID:
  final String idFileName = IndexFileNames.segmentFileName(readState.segmentInfo.name, readState.segmentSuffix, ID_EXTENSION);
  IndexInput in = readState.directory.openInput(idFileName, readState.context);
  boolean success = false;
  final int id;
  try {
    CodecUtil.checkHeader(in, RAM_ONLY_NAME, VERSION_START, VERSION_LATEST);
    id = in.readVInt();
    success = true;
  } finally {
    if (!success) {
      IOUtils.closeWhileHandlingException(in);
    } else {
      IOUtils.close(in);
    }
  }
  
  synchronized(state) {
    return state.get(id);
  }
}
 

public void testRandom() throws Exception {

    int iters = 5;

    for(int iter=0;iter<iters;iter++) {
      Path path = createTempDir("testPostingsFormat");
      Directory dir = newFSDirectory(path);

      boolean indexPayloads = random().nextBoolean();
      // TODO test thread safety of buildIndex too
      FieldsProducer fieldsProducer = postingsTester.buildIndex(getCodec(), dir, IndexOptions.DOCS_AND_FREQS_AND_POSITIONS_AND_OFFSETS, indexPayloads, false);

      postingsTester.testFields(fieldsProducer);

      // NOTE: you can also test "weaker" index options than
      // you indexed with:
      postingsTester.testTerms(fieldsProducer, EnumSet.allOf(RandomPostingsTester.Option.class), IndexOptions.DOCS_AND_FREQS_AND_POSITIONS_AND_OFFSETS, IndexOptions.DOCS_AND_FREQS_AND_POSITIONS_AND_OFFSETS, false);

      fieldsProducer.close();
      fieldsProducer = null;

      dir.close();
    }
  }
 

public void testPostingsEnumReuse() throws Exception {

    Path path = createTempDir("testPostingsEnumReuse");
    Directory dir = newFSDirectory(path);

    FieldsProducer fieldsProducer = postingsTester.buildIndex(getCodec(), dir, IndexOptions.DOCS_AND_FREQS_AND_POSITIONS_AND_OFFSETS, random().nextBoolean(), true);
    Collections.shuffle(postingsTester.allTerms, random());
    RandomPostingsTester.FieldAndTerm fieldAndTerm = postingsTester.allTerms.get(0);

    Terms terms = fieldsProducer.terms(fieldAndTerm.field);
    TermsEnum te = terms.iterator();

    te.seekExact(fieldAndTerm.term);
    checkReuse(te, PostingsEnum.FREQS, PostingsEnum.ALL, false);
    if (isPostingsEnumReuseImplemented()) {
      checkReuse(te, PostingsEnum.ALL, PostingsEnum.ALL, true);
    }

    fieldsProducer.close();
    dir.close();
  }
 

/** Indexes all fields/terms at the specified
 *  IndexOptions, and fully tests at that IndexOptions. */
public void testFull(Codec codec, Path path, IndexOptions options, boolean withPayloads) throws Exception {
  Directory dir = LuceneTestCase.newFSDirectory(path);

  // TODO test thread safety of buildIndex too
  FieldsProducer fieldsProducer = buildIndex(codec, dir, options, withPayloads, true);

  testFields(fieldsProducer);

  IndexOptions[] allOptions = IndexOptions.values();
  int maxIndexOption = Arrays.asList(allOptions).indexOf(options);

  for(int i=0;i<=maxIndexOption;i++) {
    testTerms(fieldsProducer, EnumSet.allOf(Option.class), allOptions[i], options, true);
    if (withPayloads) {
      // If we indexed w/ payloads, also test enums w/o accessing payloads:
      testTerms(fieldsProducer, EnumSet.complementOf(EnumSet.of(Option.PAYLOADS)), allOptions[i], options, true);
    }
  }

  fieldsProducer.close();
  dir.close();
}
 

@Override
public void merge(MergeState mergeState) throws IOException {
  final List<Fields> fields = new ArrayList<>();
  final List<ReaderSlice> slices = new ArrayList<>();

  int docBase = 0;

  for (int readerIndex = 0; readerIndex < mergeState.fieldsProducers.length; readerIndex++) {
    final FieldsProducer f = mergeState.fieldsProducers[readerIndex];

    final int maxDoc = mergeState.maxDocs[readerIndex];
    f.checkIntegrity();
    slices.add(new ReaderSlice(docBase, maxDoc, readerIndex));
    fields.add(f);
    docBase += maxDoc;
  }

  Fields mergedFields = new MappedMultiFields(mergeState,
      new MultiFields(fields.toArray(Fields.EMPTY_ARRAY),
          slices.toArray(ReaderSlice.EMPTY_ARRAY)));
  write(mergedFields);
}
 

public CompletionFieldsProducer(SegmentReadState state) throws IOException {
    String suggestFSTFile = IndexFileNames.segmentFileName(state.segmentInfo.name, state.segmentSuffix, EXTENSION);
    IndexInput input = state.directory.openInput(suggestFSTFile, state.context);
    version = CodecUtil.checkHeader(input, CODEC_NAME, SUGGEST_CODEC_VERSION, SUGGEST_VERSION_CURRENT);
    FieldsProducer delegateProducer = null;
    boolean success = false;
    try {
        PostingsFormat delegatePostingsFormat = PostingsFormat.forName(input.readString());
        String providerName = input.readString();
        CompletionLookupProvider completionLookupProvider = providers.get(providerName);
        if (completionLookupProvider == null) {
            throw new IllegalStateException("no provider with name [" + providerName + "] registered");
        }
        // TODO: we could clone the ReadState and make it always forward IOContext.MERGE to prevent unecessary heap usage?
        delegateProducer = delegatePostingsFormat.fieldsProducer(state);
        /*
         * If we are merging we don't load the FSTs at all such that we
         * don't consume so much memory during merge
         */
        if (state.context.context != Context.MERGE) {
            // TODO: maybe we can do this in a fully lazy fashion based on some configuration
            // eventually we should have some kind of curciut breaker that prevents us from going OOM here
            // with some configuration
            this.lookupFactory = completionLookupProvider.load(input);
        } else {
            this.lookupFactory = null;
        }
        this.delegateProducer = delegateProducer;
        success = true;
    } finally {
        if (!success) {
            IOUtils.closeWhileHandlingException(delegateProducer, input);
        } else {
            IOUtils.close(input);
        }
    }
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  PostingsReaderBase postingsReader = new Lucene84PostingsReader(state);
  boolean success = false;
  try {
    FieldsProducer ret = new FSTTermsReader(state, postingsReader);
    success = true;
    return ret;
  } finally {
    if (!success) {
      IOUtils.closeWhileHandlingException(postingsReader);
    }
  }
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  PostingsReaderBase postingsReader = new Lucene84PostingsReader(state);
  boolean success = false;
  try {
    FieldsProducer ret = new OrdsBlockTreeTermsReader(postingsReader, state);
    success = true;
    return ret;
  } finally {
    if (!success) {
      IOUtils.closeWhileHandlingException(postingsReader);
    }
  }
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  PostingsReaderBase postingsReader = new Lucene84PostingsReader(state);
  boolean success = false;
  try {
    FieldsProducer termsReader = createUniformSplitTermsReader(postingsReader, state, blockDecoder);
    success = true;
    return termsReader;
  } finally {
    if (!success) {
      IOUtils.closeWhileHandlingException(postingsReader);
    }
  }
}
 

@Override
public void merge(MergeState mergeState, NormsProducer normsProducer) throws IOException {
  if (mergeState.needsIndexSort) {
    // This custom merging does not support sorted index.
    // Fall back to the default merge, which is inefficient for this postings format.
    super.merge(mergeState, normsProducer);
    return;
  }
  FieldsProducer[] fieldsProducers = mergeState.fieldsProducers;
  List<TermIterator<SegmentTerms>> segmentTermsList = new ArrayList<>(fieldsProducers.length);
  for (int segmentIndex = 0; segmentIndex < fieldsProducers.length; segmentIndex++) {
    FieldsProducer fieldsProducer = fieldsProducers[segmentIndex];
    // Iterate the FieldInfo provided by mergeState.fieldInfos because they may be
    // filtered by PerFieldMergeState.
    for (FieldInfo fieldInfo : mergeState.fieldInfos[segmentIndex]) {
      // Iterate all fields only the get the *first* Terms instanceof STUniformSplitTerms.
      // See the break below.
      Terms terms = fieldsProducer.terms(fieldInfo.name);
      if (terms != null) {
        if (!(terms instanceof STUniformSplitTerms)) {
          // Terms is not directly an instance of STUniformSplitTerms, it is wrapped/filtered.
          // Fall back to the default merge, which is inefficient for this postings format.
          super.merge(mergeState, normsProducer);
          return;
        }
        STUniformSplitTerms sharedTerms = (STUniformSplitTerms) terms;
        segmentTermsList.add(new SegmentTerms(
            segmentIndex, sharedTerms.createMergingBlockReader(), mergeState.docMaps[segmentIndex]));
        // We have the STUniformSplitTerms for the segment. Break the field
        // loop to iterate the next segment.
        break;
      }
    }
  }
  writeSegment((blockWriter, dictionaryBuilder) -> mergeSegments(mergeState, normsProducer, segmentTermsList, blockWriter, dictionaryBuilder));
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  PostingsReaderBase postingsReader = new IDVersionPostingsReader();
  boolean success = false;
   try {
     FieldsProducer ret = new VersionBlockTreeTermsReader(postingsReader, state);
     success = true;
     return ret;
   } finally {
     if (!success) {
       IOUtils.closeWhileHandlingException(postingsReader);
     }
   }
}
 

AssertingFieldsProducer(FieldsProducer in) {
  this.in = in;
  // do a few simple checks on init
  assert toString() != null;
  assert ramBytesUsed() >= 0;
  assert getChildResources() != null;
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  PostingsReaderBase postings = new Lucene84PostingsReader(state);
  TermsIndexReaderBase indexReader;

  boolean success = false;
  try {
    indexReader = new VariableGapTermsIndexReader(state);
    success = true;
  } finally {
    if (!success) {
      postings.close();
    }
  }

  success = false;
  try {
    FieldsProducer ret = new BlockTermsReader(indexReader, postings, state);
    success = true;
    return ret;
  } finally {
    if (!success) {
      try {
        postings.close();
      } finally {
        indexReader.close();
      }
    }
  }
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  PostingsReaderBase postings = new Lucene84PostingsReader(state);
  TermsIndexReaderBase indexReader;

  boolean success = false;
  try {
    indexReader = new FixedGapTermsIndexReader(state);
    success = true;
  } finally {
    if (!success) {
      postings.close();
    }
  }

  success = false;
  try {
    FieldsProducer ret = new BlockTermsReader(indexReader, postings, state);
    success = true;
    return ret;
  } finally {
    if (!success) {
      try {
        postings.close();
      } finally {
        indexReader.close();
      }
    }
  }
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  PostingsReaderBase postings = new Lucene84PostingsReader(state);
  TermsIndexReaderBase indexReader;

  boolean success = false;
  try {
    indexReader = new VariableGapTermsIndexReader(state);
    success = true;
  } finally {
    if (!success) {
      postings.close();
    }
  }

  success = false;
  try {
    FieldsProducer ret = new BlockTermsReader(indexReader, postings, state);
    success = true;
    return ret;
  } finally {
    if (!success) {
      try {
        postings.close();
      } finally {
        indexReader.close();
      }
    }
  }
}
 

@Override
public void merge(MergeState mergeState, NormsProducer norms) throws IOException {
  @SuppressWarnings("unchecked") Iterable<String> indexedFieldNames = () ->
      new MergedIterator<>(true,
          Arrays.stream(mergeState.fieldsProducers).map(FieldsProducer::iterator).toArray(Iterator[]::new));
  Map<PostingsFormat, FieldsGroup> formatToGroups = buildFieldsGroupMapping(indexedFieldNames);

  // Merge postings
  PerFieldMergeState pfMergeState = new PerFieldMergeState(mergeState);
  boolean success = false;
  try {
    for (Map.Entry<PostingsFormat, FieldsGroup> ent : formatToGroups.entrySet()) {
      PostingsFormat format = ent.getKey();
      final FieldsGroup group = ent.getValue();

      FieldsConsumer consumer = format.fieldsConsumer(group.state);
      toClose.add(consumer);
      consumer.merge(pfMergeState.apply(group.fields), norms);
    }
    success = true;
  } finally {
    pfMergeState.reset();
    if (!success) {
      IOUtils.closeWhileHandlingException(toClose);
    }
  }
}
 

PerFieldMergeState(MergeState in) {
  this.in = in;
  this.orgMergeFieldInfos = in.mergeFieldInfos;
  this.orgFieldInfos = new FieldInfos[in.fieldInfos.length];
  this.orgFieldsProducers = new FieldsProducer[in.fieldsProducers.length];

  System.arraycopy(in.fieldInfos, 0, this.orgFieldInfos, 0, this.orgFieldInfos.length);
  System.arraycopy(in.fieldsProducers, 0, this.orgFieldsProducers, 0, this.orgFieldsProducers.length);
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  PostingsReaderBase postingsReader = new Lucene84PostingsReader(state);
  boolean success = false;
  try {
    FieldsProducer ret = new BlockTreeTermsReader(postingsReader, state);
    success = true;
    return ret;
  } finally {
    if (!success) {
      IOUtils.closeWhileHandlingException(postingsReader);
    }
  }
}
 

MergeReaderWrapper(CodecReader in) throws IOException {
  this.in = in;
  
  FieldsProducer fields = in.getPostingsReader();
  if (fields != null) {
    fields = fields.getMergeInstance();
  }
  this.fields = fields;
  
  NormsProducer norms = in.getNormsReader();
  if (norms != null) {
    norms = norms.getMergeInstance();
  }
  this.norms = norms;
  
  DocValuesProducer docValues = in.getDocValuesReader();
  if (docValues != null) {
    docValues = docValues.getMergeInstance();
  }
  this.docValues = docValues;
  
  StoredFieldsReader store = in.getFieldsReader();
  if (store != null) {
    store = store.getMergeInstance();
  }
  this.store = store;
  
  TermVectorsReader vectors = in.getTermVectorsReader();
  if (vectors != null) {
    vectors = vectors.getMergeInstance();
  }
  this.vectors = vectors;
}
 

private static FieldsProducer readerToFieldsProducer(final LeafReader reader) throws IOException {
  ArrayList<String> indexedFields = new ArrayList<>();
  for (FieldInfo fieldInfo : reader.getFieldInfos()) {
    if (fieldInfo.getIndexOptions() != IndexOptions.NONE) {
      indexedFields.add(fieldInfo.name);
    }
  }
  Collections.sort(indexedFields);
  return new FieldsProducer() {
    @Override
    public Iterator<String> iterator() {
      return indexedFields.iterator();
    }

    @Override
    public Terms terms(String field) throws IOException {
      return reader.terms(field);
    }

    @Override
    public int size() {
      return indexedFields.size();
    }

    @Override
    public void checkIntegrity() throws IOException {
      // We already checkIntegrity the entire reader up front
    }

    @Override
    public void close() {
    }

    @Override
    public long ramBytesUsed() {
      return 0;
    }
  };
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  PostingsReaderBase postingsReader = new Lucene50PostingsReader(state);
  boolean success = false;
  try {
    FieldsProducer ret = new BlockTreeTermsReader(postingsReader, state);
    success = true;
    return ret;
  } finally {
    if (!success) {
      IOUtils.closeWhileHandlingException(postingsReader);
    }
  }
}
 

@Override
public FieldsProducer getMergeInstance() throws IOException {
    return delegateProducer.getMergeInstance();
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
    // we can just return the delegate here since we didn't record bloom filters for 
    // the other fields. 
    return bloomPostings.fieldsProducer(state);
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state) throws IOException {
  return new SimpleTextFieldsReader(state);
}
 

@Override
public FieldsProducer fieldsProducer(SegmentReadState state)
    throws IOException {
  return new BloomFilteredFieldsProducer(state);
}
 

protected FieldsProducer createUniformSplitTermsReader(PostingsReaderBase postingsReader, SegmentReadState state,
                                             BlockDecoder blockDecoder) throws IOException {
  return new UniformSplitTermsReader(postingsReader, state, blockDecoder, dictionaryOnHeap);
}
 

@Override
protected FieldsProducer createUniformSplitTermsReader(PostingsReaderBase postingsReader, SegmentReadState state,
                                             BlockDecoder blockDecoder) throws IOException {
  return new STUniformSplitTermsReader(postingsReader, state, blockDecoder, dictionaryOnHeap);
}
 

private CompletionFieldsProducer(FieldsProducer delegateFieldsProducer, Map<String, CompletionsTermsReader> readers) {
  this.delegateFieldsProducer = delegateFieldsProducer;
  this.readers = readers;
}
 

@Override
public FieldsProducer getMergeInstance() {
  return new CompletionFieldsProducer(delegateFieldsProducer, readers);
}