How to use

emptyNumeric

method

in

org.apache.lucene.index.DocValues

@Override
public NumericDocValues getNormValues( String field )
{
  return DocValues.emptyNumeric();
}

/**
 * Returns NumericDocValues for the field, or {@link #emptyNumeric()} if it has none.
 * @return docvalues instance, or an empty instance if {@code field} does not exist in this reader.
 * @throws IllegalStateException if {@code field} exists, but was not indexed with docvalues.
 * @throws IllegalStateException if {@code field} has docvalues, but the type is not {@link DocValuesType#NUMERIC}.
 * @throws IOException if an I/O error occurs.
 */
public static NumericDocValues getNumeric(LeafReader reader, String field) throws IOException {
 NumericDocValues dv = reader.getNumericDocValues(field);
 if (dv == null) {
  checkField(reader, field, DocValuesType.NUMERIC);
  return emptyNumeric();
 } else {
  return dv;
 }
}

if (entry.docsWithFieldOffset == -2) {
 return DocValues.emptyNumeric();
} else if (entry.docsWithFieldOffset == -1) {

private NumericDocValues getNumeric(NumericEntry entry) throws IOException {
 if (entry.docsWithFieldOffset == -2) {
  return DocValues.emptyNumeric();
 } else if (entry.docsWithFieldOffset == -1) {

return FieldData.replaceMissing(DocValues.emptyNumeric(), missingValue);

DocValuesType type = getDocValuesType(reader, field);
if (type == null || type == DocValuesType.NONE) {
  values = DocValues.emptyNumeric();
  return ;

@Override
public NumericDocValues getNorms(FieldInfo field) throws IOException {
 return DocValues.emptyNumeric();
}

@Override
public synchronized NumericDocValues getNorms(FieldInfo field) throws IOException {
 if (UndeadNormsProducer.isUndead(field)) {
  // Bring undead norms back to life; this is set in Lucene46FieldInfosFormat, to emulate pre-5.0 undead norms
  return DocValues.emptyNumeric();
 }
 NumericDocValues instance = instances.get(field.name);
 if (instance == null) {
  instance = loadNorms(field);
  if (!merging) {
   instances.put(field.name, instance);
   activeCount.incrementAndGet();
  }
 }
 return instance;
}

/**
 * An empty SortedNumericDocValues which returns zero values for every document 
 */
public static final SortedNumericDocValues emptySortedNumeric(int maxDoc) {
 return singleton(emptyNumeric(), new Bits.MatchNoBits(maxDoc));
}

@Override
public NumericDocValues getNorms(FieldInfo field) throws IOException {
 if (UndeadNormsProducer.isUndead(field)) {
  // Bring undead norms back to life; this is set in Lucene40FieldInfosFormat, to emulate pre-5.0 undead norms
  return DocValues.emptyNumeric();
 }
 return impl.getNumeric(field);
}

/**
 * An empty SortedNumericDocValues which returns zero values for every document 
 */
public static final SortedNumericDocValues emptySortedNumeric(int maxDoc) {
 return singleton(emptyNumeric(), new Bits.MatchNoBits(maxDoc));
}

@Override
public NumericDocValues getNorms(FieldInfo field) throws IOException {
 if (UndeadNormsProducer.isUndead(field)) {
  // Bring undead norms back to life; this is set in Lucene42FieldInfosFormat, to emulate pre-5.0 undead norms
  return DocValues.emptyNumeric();
 }
 return impl.getNumeric(field);
}

/**
 * Returns NumericDocValues for the field, or {@link #emptyNumeric()} if it has none.
 * @return docvalues instance, or an empty instance if {@code field} does not exist in this reader.
 * @throws IllegalStateException if {@code field} exists, but was not indexed with docvalues.
 * @throws IllegalStateException if {@code field} has docvalues, but the type is not {@link DocValuesType#NUMERIC}.
 * @throws IOException if an I/O error occurs.
 */
public static NumericDocValues getNumeric(LeafReader reader, String field) throws IOException {
 NumericDocValues dv = reader.getNumericDocValues(field);
 if (dv == null) {
  checkField(reader, field, DocValuesType.NUMERIC);
  return emptyNumeric();
 } else {
  return dv;
 }
}

/**
 * Returns NumericDocValues for the field, or {@link #emptyNumeric()} if it has none. 
 * @return docvalues instance, or an empty instance if {@code field} does not exist in this reader.
 * @throws IllegalStateException if {@code field} exists, but was not indexed with docvalues.
 * @throws IllegalStateException if {@code field} has docvalues, but the type is not {@link DocValuesType#NUMERIC}.
 * @throws IOException if an I/O error occurs.
 */
public static NumericDocValues getNumeric(LeafReader reader, String field) throws IOException {
 NumericDocValues dv = reader.getNumericDocValues(field);
 if (dv == null) {
  checkField(reader, field, DocValuesType.NUMERIC);
  return emptyNumeric();
 } else {
  return dv;
 }
}

/**
 * Returns NumericDocValues for the field, or {@link #emptyNumeric()} if it has none. 
 * @return docvalues instance, or an empty instance if {@code field} does not exist in this reader.
 * @throws IllegalStateException if {@code field} exists, but was not indexed with docvalues.
 * @throws IllegalStateException if {@code field} has docvalues, but the type is not {@link DocValuesType#NUMERIC}.
 * @throws IOException if an I/O error occurs.
 */
public static NumericDocValues getNumeric(LeafReader reader, String field) throws IOException {
 NumericDocValues dv = reader.getNumericDocValues(field);
 if (dv == null) {
  checkField(reader, field, DocValuesType.NUMERIC);
  return emptyNumeric();
 } else {
  return dv;
 }
}

@Override
public NumericDocValues getNumerics(LeafReader reader, String field, Parser parser, boolean setDocsWithField) throws IOException {
 if (parser == null) {
  throw new NullPointerException();
 }
 final NumericDocValues valuesIn = reader.getNumericDocValues(field);
 if (valuesIn != null) {
  // Not cached here by FieldCacheImpl (cached instead
  // per-thread by SegmentReader):
  return valuesIn;
 } else {
  final FieldInfo info = reader.getFieldInfos().fieldInfo(field);
  if (info == null) {
   return DocValues.emptyNumeric();
  } else if (info.getDocValuesType() != DocValuesType.NONE) {
   throw new IllegalStateException("Type mismatch: " + field + " was indexed as " + info.getDocValuesType());
  } else if (info.getIndexOptions() == IndexOptions.NONE) {
   return DocValues.emptyNumeric();
  }
  return (NumericDocValues) caches.get(Long.TYPE).get(reader, new CacheKey(field, parser), setDocsWithField);
 }
}

@Override
protected NumericDocValues getNumericDocValues(LeafReaderContext context, String field) throws IOException {
 SortedNumericDocValues sortedNumeric = DocValues.getSortedNumeric(context.reader(), field);
 final BlockJoinSelector.Type type = order
   ? BlockJoinSelector.Type.MAX
   : BlockJoinSelector.Type.MIN;
 final BitSet parents = parentFilter.getBitSet(context);
 final BitSet children = childFilter.getBitSet(context);
 if (children == null) {
  return DocValues.emptyNumeric();
 }
 return BlockJoinSelector.wrap(sortedNumeric, type, parents, children);
}
@Override

@Override
protected NumericDocValues getNumericDocValues(LeafReaderContext context, String field) throws IOException {
 SortedNumericDocValues sortedNumeric = DocValues.getSortedNumeric(context.reader(), field);
 final BlockJoinSelector.Type type = order
   ? BlockJoinSelector.Type.MAX
   : BlockJoinSelector.Type.MIN;
 final BitSet parents = parentFilter.getBitSet(context);
 final BitSet children = childFilter.getBitSet(context);
 if (children == null) {
  return DocValues.emptyNumeric();
 }
 return BlockJoinSelector.wrap(sortedNumeric, type, parents, children);
}
@Override

@Override
protected NumericDocValues getNumericDocValues(LeafReaderContext context, String field) throws IOException {
 SortedNumericDocValues sortedNumeric = DocValues.getSortedNumeric(context.reader(), field);
 final BlockJoinSelector.Type type = order
   ? BlockJoinSelector.Type.MAX
   : BlockJoinSelector.Type.MIN;
 final BitSet parents = parentFilter.getBitSet(context);
 final BitSet children = childFilter.getBitSet(context);
 if (children == null) {
  return DocValues.emptyNumeric();
 }
 final NumericDocValues view = BlockJoinSelector.wrap(sortedNumeric, type, parents, children);
 // undo the numericutils sortability
 return new NumericDocValues() {
  @Override
  public long get(int docID) {
   return NumericUtils.sortableDoubleBits(view.get(docID));
  }
 };
}
@Override

 @Override
 protected NumericDocValues getNumericDocValues(LeafReaderContext context, String field) throws IOException {
  SortedNumericDocValues sortedNumeric = DocValues.getSortedNumeric(context.reader(), field);
  final BlockJoinSelector.Type type = order
    ? BlockJoinSelector.Type.MAX
    : BlockJoinSelector.Type.MIN;
  final BitSet parents = parentFilter.getBitSet(context);
  final BitSet children = childFilter.getBitSet(context);
  if (children == null) {
   return DocValues.emptyNumeric();
  }
  final NumericDocValues view = BlockJoinSelector.wrap(sortedNumeric, type, parents, children);
  // undo the numericutils sortability
  return new NumericDocValues() {
   @Override
   public long get(int docID) {
    return NumericUtils.sortableFloatBits((int) view.get(docID));
   }
  };
 }
};