How to use

Reference2ReferenceMaps

in

it.unimi.dsi.fastutil.objects

public Reference2ReferenceMap<Index, IntervalIterator> intervalIterators() {
  return Reference2ReferenceMaps.singleton( soleIndex, IntervalIterators.TRUE );
}

/**
 * Returns a hash code for this map.
 *
 * The hash code of a map is computed by summing the hash codes of its entries.
 *
 * @return a hash code for this map.
 */
@Override
public int hashCode() {
  int h = 0, n = size();
  final ObjectIterator<Reference2ReferenceMap.Entry<K, V>> i = Reference2ReferenceMaps.fastIterator(this);
  while (n-- != 0)
    h += i.next().hashCode();
  return h;
}
@Override

/** Creates a new remapping document iterator wrapping a given document iterator and remapping interval-iterator requests
 * through a given mapping from external to internal indices.
 * 
 * @param documentIterator the underlying document iterator.
 * @param indexInverseRemapping the mapping from external to internal indices.
 */
public RemappingDocumentIterator( final DocumentIterator documentIterator, final Reference2ReferenceMap<? extends Index, ? extends Index> indexInverseRemapping ) {
  this.documentIterator = documentIterator;
  this.indexInverseRemapping = indexInverseRemapping;
  final int n = documentIterator.indices().size();
  this.currentIterators = new Index2IntervalIteratorMap( n );
  this.unmodifiableCurrentIterators = Reference2ReferenceMaps.unmodifiable( currentIterators );
  indices = new ReferenceArraySet<Index>( documentIterator.indices().size() );
  final ReferenceArraySet<Index> nonIndices = new ReferenceArraySet<Index>();
  for( Map.Entry<? extends Index, ? extends Index> e : indexInverseRemapping.entrySet() ) {
    if ( documentIterator.indices().contains( e.getKey() ) ) throw new IllegalArgumentException( "You cannot remap index " + e.getValue() + " to index " + e.getKey() + " as the latter already belongs to the document iterator" );
    if ( ! documentIterator.indices().contains( e.getValue() ) ) throw new IllegalArgumentException( "You cannot remap index " + e.getValue() + " to index " + e.getKey() + " as the former does not belong to the document iterator" );
    nonIndices.add( e.getValue() );
    indices.add( e.getKey() );
  }
  
  for( Index index: documentIterator.indices() ) if ( ! nonIndices.contains( index ) ) indices.add( index );
  soleIndex = n == 1 ? indices.iterator().next() : null;
}

/** Creates a new remapping document iterator wrapping a given document iterator and remapping interval-iterator requests
 * through a given mapping from external to internal indices.
 * 
 * @param documentIterator the underlying document iterator.
 * @param indexInverseRemapping the mapping from external to internal indices.
 */
public RemappingDocumentIterator( final DocumentIterator documentIterator, final Reference2ReferenceMap<? extends Index, ? extends Index> indexInverseRemapping ) {
  this.documentIterator = documentIterator;
  this.indexInverseRemapping = indexInverseRemapping;
  final int n = documentIterator.indices().size();
  this.currentIterators = new Reference2ReferenceArrayMap<Index,IntervalIterator>( new Index[ n ], new IntervalIterator[ n ] );
  this.unmodifiableCurrentIterators = Reference2ReferenceMaps.unmodifiable( currentIterators );
  indices = new ReferenceArraySet<Index>( documentIterator.indices().size() );
  final ReferenceArraySet<Index> nonIndices = new ReferenceArraySet<Index>();
  for( Map.Entry<? extends Index, ? extends Index> e : indexInverseRemapping.entrySet() ) {
    if ( documentIterator.indices().contains( e.getKey() ) ) throw new IllegalArgumentException( "You cannot remap index " + e.getValue() + " to index " + e.getKey() + " as the latter already belongs to the document iterator" );
    if ( ! documentIterator.indices().contains( e.getValue() ) ) throw new IllegalArgumentException( "You cannot remap index " + e.getValue() + " to index " + e.getKey() + " as the former does not belong to the document iterator" );
    nonIndices.add( e.getValue() );
    indices.add( e.getKey() );
  }
  
  for( Index index: documentIterator.indices() ) if ( ! nonIndices.contains( index ) ) indices.add( index );
  soleIndex = n == 1 ? indices.iterator().next() : null;
}

/** Creates a new remapping document iterator wrapping a given document iterator and remapping interval-iterator requests
 * through a given mapping from external to internal indices.
 * 
 * @param documentIterator the underlying document iterator.
 * @param indexInverseRemapping the mapping from external to internal indices.
 */
public RemappingDocumentIterator( final DocumentIterator documentIterator, final Reference2ReferenceMap<? extends Index, ? extends Index> indexInverseRemapping ) {
  this.documentIterator = documentIterator;
  this.indexInverseRemapping = indexInverseRemapping;
  final int n = documentIterator.indices().size();
  this.currentIterators = new Index2IntervalIteratorMap( n );
  this.unmodifiableCurrentIterators = Reference2ReferenceMaps.unmodifiable( currentIterators );
  indices = new ReferenceArraySet<Index>( documentIterator.indices().size() );
  final ReferenceArraySet<Index> nonIndices = new ReferenceArraySet<Index>();
  for( Map.Entry<? extends Index, ? extends Index> e : indexInverseRemapping.entrySet() ) {
    if ( documentIterator.indices().contains( e.getKey() ) ) throw new IllegalArgumentException( "You cannot remap index " + e.getValue() + " to index " + e.getKey() + " as the latter already belongs to the document iterator" );
    if ( ! documentIterator.indices().contains( e.getValue() ) ) throw new IllegalArgumentException( "You cannot remap index " + e.getValue() + " to index " + e.getKey() + " as the former does not belong to the document iterator" );
    nonIndices.add( e.getValue() );
    indices.add( e.getKey() );
  }
  
  for( Index index: documentIterator.indices() ) if ( ! nonIndices.contains( index ) ) indices.add( index );
  soleIndex = n == 1 ? indices.iterator().next() : null;
}

public Reference2ReferenceMap<Index, IntervalIterator> intervalIterators() {
  return Reference2ReferenceMaps.singleton( soleIndex, IntervalIterators.TRUE );
}

  @Override
  public String toString() {
    final StringBuilder s = new StringBuilder();
    final ObjectIterator<Reference2ReferenceMap.Entry<K, V>> i = Reference2ReferenceMaps.fastIterator(this);
    int n = size();
    Reference2ReferenceMap.Entry<K, V> e;
    boolean first = true;
    s.append("{");
    while (n-- != 0) {
      if (first)
        first = false;
      else
        s.append(", ");
      e = i.next();
      if (this == e.getKey())
        s.append("(this map)");
      else
        s.append(String.valueOf(e.getKey()));
      s.append("=>");
      if (this == e.getValue())
        s.append("(this map)");
      else
        s.append(String.valueOf(e.getValue()));
    }
    s.append("}");
    return s.toString();
  }
}

protected AlignDocumentIterator( final DocumentIterator firstIterator, final DocumentIterator secondIterator ) {
  this.firstIterator = firstIterator;
  this.secondIterator = secondIterator;
  if ( firstIterator instanceof IndexIterator && secondIterator instanceof IndexIterator ) {
    firstIndexIterator = (IndexIterator)firstIterator; 
    secondIndexIterator = (IndexIterator)secondIterator;
  }
  else firstIndexIterator = secondIndexIterator = null;
  if ( firstIterator.indices().size() != 1 || secondIterator.indices().size() != 1 ) throw new IllegalArgumentException( "You can align single-index iterators only" );
  index = firstIterator.indices().iterator().next();
  currentIterators = new Reference2ReferenceArrayMap<Index,IntervalIterator>( 1 );
  unmodifiableCurrentIterators = Reference2ReferenceMaps.unmodifiable( currentIterators );
}

protected TrueDocumentIterator( final Index index ) {
  indices = ReferenceSets.singleton( soleIndex = index );
  intervalIterators = Reference2ReferenceMaps.singleton( soleIndex, IntervalIterators.TRUE );
}

/** {@inheritDoc} */
@SuppressWarnings({"unchecked", "deprecation"})
@Override
public void putAll(final Map<? extends K, ? extends V> m) {
  if (m instanceof Reference2ReferenceMap) {
    ObjectIterator<Reference2ReferenceMap.Entry<K, V>> i = Reference2ReferenceMaps
        .fastIterator((Reference2ReferenceMap<K, V>) m);
    while (i.hasNext()) {
      final Reference2ReferenceMap.Entry<? extends K, ? extends V> e = i.next();
      put(e.getKey(), e.getValue());
    }
  } else {
    int n = m.size();
    final Iterator<? extends Map.Entry<? extends K, ? extends V>> i = m.entrySet().iterator();
    Map.Entry<? extends K, ? extends V> e;
    while (n-- != 0) {
      e = i.next();
      put(e.getKey(), e.getValue());
    }
  }
}
/**

/** Creates a new remapping document iterator wrapping a given document iterator and remapping interval-iterator requests
 * through a given mapping from external to internal indices.
 * 
 * @param documentIterator the underlying document iterator.
 * @param indexInverseRemapping the mapping from external to internal indices.
 */
public RemappingDocumentIterator( final DocumentIterator documentIterator, final Reference2ReferenceMap<? extends Index, ? extends Index> indexInverseRemapping ) {
  this.documentIterator = documentIterator;
  this.indexInverseRemapping = indexInverseRemapping;
  final int n = documentIterator.indices().size();
  this.currentIterators = new Reference2ReferenceArrayMap<Index,IntervalIterator>( new Index[ n ], new IntervalIterator[ n ] );
  this.unmodifiableCurrentIterators = Reference2ReferenceMaps.unmodifiable( currentIterators );
  indices = new ReferenceArraySet<Index>( documentIterator.indices().size() );
  final ReferenceArraySet<Index> nonIndices = new ReferenceArraySet<Index>();
  for( Map.Entry<? extends Index, ? extends Index> e : indexInverseRemapping.entrySet() ) {
    if ( documentIterator.indices().contains( e.getKey() ) ) throw new IllegalArgumentException( "You cannot remap index " + e.getValue() + " to index " + e.getKey() + " as the latter already belongs to the document iterator" );
    if ( ! documentIterator.indices().contains( e.getValue() ) ) throw new IllegalArgumentException( "You cannot remap index " + e.getValue() + " to index " + e.getKey() + " as the former does not belong to the document iterator" );
    nonIndices.add( e.getValue() );
    indices.add( e.getKey() );
  }
  
  for( Index index: documentIterator.indices() ) if ( ! nonIndices.contains( index ) ) indices.add( index );
  soleIndex = n == 1 ? indices.iterator().next() : null;
}

protected AbstractQuasiSuccinctIndexIterator( final QuasiSuccinctIndexReader indexReader ) {
  this.indexReader = indexReader;
  index = indexReader.index;
  keyIndex = index.keyIndex;
  hasPositions = index.hasPositions;
  hasCounts = index.hasCounts;
  numberOfDocuments = index.numberOfDocuments;
  pointersList = indexReader.pointersList;
  countsList = indexReader.countsList;
  positionsList = indexReader.positionsList;
  intervalIterator = hasPositions ? new IndexIntervalIterator( this ) : IntervalIterators.FALSE; 
  singletonIntervalIterator = Reference2ReferenceMaps.singleton( keyIndex, hasPositions ? intervalIterator : IntervalIterators.FALSE );
  currentTerm = frequency = -1;
}

protected AlignDocumentIterator( final DocumentIterator firstIterator, final DocumentIterator secondIterator ) {
  this.firstIterator = firstIterator;
  this.secondIterator = secondIterator;
  if ( firstIterator instanceof IndexIterator && secondIterator instanceof IndexIterator ) {
    firstIndexIterator = (IndexIterator)firstIterator; 
    secondIndexIterator = (IndexIterator)secondIterator;
  }
  else firstIndexIterator = secondIndexIterator = null;
  if ( firstIterator.indices().size() != 1 || secondIterator.indices().size() != 1 ) throw new IllegalArgumentException( "You can align single-index iterators only" );
  index = firstIterator.indices().iterator().next();
  currentIterators = new Reference2ReferenceArrayMap<Index,IntervalIterator>( 1 );
  unmodifiableCurrentIterators = Reference2ReferenceMaps.unmodifiable( currentIterators );
}

protected TrueDocumentIterator( final Index index ) {
  indices = ReferenceSets.singleton( soleIndex = index );
  intervalIterators = Reference2ReferenceMaps.singleton( soleIndex, IntervalIterators.TRUE );
}

unmodifiableCurrentIterators = Reference2ReferenceMaps.unmodifiable( currentIterators );

protected AbstractQuasiSuccinctIndexIterator( final QuasiSuccinctIndexReader indexReader ) {
  this.indexReader = indexReader;
  index = indexReader.index;
  keyIndex = index.keyIndex;
  hasPositions = index.hasPositions;
  hasCounts = index.hasCounts;
  numberOfDocuments = index.numberOfDocuments;
  pointersList = indexReader.pointersList;
  countsList = indexReader.countsList;
  positionsList = indexReader.positionsList;
  intervalIterator = hasPositions ? new IndexIntervalIterator( this ) : null;
  singletonIntervalIterator = hasPositions ? Reference2ReferenceMaps.singleton( keyIndex, (IntervalIterator)intervalIterator ) : null;
  currentTerm = frequency = -1;
}

/** Creates a new difference document iterator given a minuend and a subtrahend iterator.
 * @param minuendIterator the minuend.
 * @param subtrahendIterator the subtrahend.
 */
protected DifferenceDocumentIterator( final DocumentIterator minuendIterator, final DocumentIterator subtrahendIterator, final int leftMargin, final int rightMargin ) {
  if ( leftMargin < 0 || rightMargin < 0 ) throw new IllegalArgumentException( "Illegal margins: " + leftMargin + ", " + rightMargin );
  this.minuendIterator = minuendIterator;
  this.subtrahendIterator = subtrahendIterator;
  this.leftMargin = leftMargin;
  this.rightMargin = rightMargin;
  final int n = minuendIterator.indices().size();
  soleIndex = n == 1 ? indices().iterator().next() : null;
  // If the subtrahend is empty, the result is equal to the minuend.
  nonEmptySubtrahend = subtrahendIterator.hasNext();
  intervalIterators = new Reference2ReferenceArrayMap<Index,IntervalIterator>( n );
  currentIterators = new Reference2ReferenceArrayMap<Index,IntervalIterator>( n );
  unmodifiableCurrentIterators = Reference2ReferenceMaps.unmodifiable( currentIterators );
}

public BitStreamIndexReaderIndexIterator( final GammaDeltaGammaDeltaBitStreamIndexReader parent, final InputBitStream ibs ) {
 this.parent = parent;
 this.ibs = ibs;
 index = parent.index;
 keyIndex = index.keyIndex;
 pointerCoding = index.pointerCoding;
 if ( index.hasPayloads ) throw new IllegalStateException();
 if ( ! index.hasCounts ) throw new IllegalStateException();
 countCoding = index.countCoding;
 if ( ! index.hasPositions ) throw new IllegalStateException();
 positionCoding = index.positionCoding;
 positionCache = new int[ POSITION_CACHE_INITIAL_SIZE ];
 intervalIterator = index.hasPositions ? new it.unimi.di.big.mg4j.index.IndexIntervalIterator( this ) : null;
 singletonIntervalIterator = index.hasPositions ? Reference2ReferenceMaps.singleton( keyIndex, (IntervalIterator)intervalIterator ) : null;
}

public CachingDocumentIterator( final DocumentIterator documentIterator ) {
  this.documentIterator = documentIterator;
  final int n = documentIterator.indices().size();
  soleIndex = n == 1 ? indices().iterator().next() : null;
  this.currentIterators = new Index2IntervalIteratorMap( n );
  this.cachingIterators = new Index2IntervalIteratorMap( n );
  this.unmodifiableCurrentIterators = Reference2ReferenceMaps.unmodifiable( currentIterators );
}

public BitStreamIndexReaderIndexIterator( final GammaDeltaGammaDeltaBitStreamIndexReader parent, final InputBitStream ibs ) {
 this.parent = parent;
 this.ibs = ibs;
 index = parent.index;
 keyIndex = index.keyIndex;
 pointerCoding = index.pointerCoding;
 if ( index.hasPayloads ) throw new IllegalStateException();
 if ( ! index.hasCounts ) throw new IllegalStateException();
 countCoding = index.countCoding;
 if ( ! index.hasPositions ) throw new IllegalStateException();
 positionCoding = index.positionCoding;
 positionCache = new int[ POSITION_CACHE_INITIAL_SIZE ];
 intervalIterator = index.hasPositions ? new it.unimi.di.mg4j.index.IndexIntervalIterator( this ) : null;
 singletonIntervalIterator = index.hasPositions ? Reference2ReferenceMaps.singleton( keyIndex, (IntervalIterator)intervalIterator ) : null;
}
/** Positions the index on the inverted list of a given term.