GlobalDictionaryBuilder.java 文件源码

private static VectorContainer buildDoubleGlobalDictionary(List<Dictionary> dictionaries, VectorContainer existingDict, ColumnDescriptor columnDescriptor, BufferAllocator bufferAllocator) {
  final Field field = new Field(SchemaPath.getCompoundPath(columnDescriptor.getPath()).getAsUnescapedPath(), true, new ArrowType.FloatingPoint(FloatingPointPrecision.DOUBLE), null);
  final VectorContainer input = new VectorContainer(bufferAllocator);
  final NullableFloat8Vector doubleVector = input.addOrGet(field);
  doubleVector.allocateNew();
  SortedSet<Double> values = Sets.newTreeSet();
  for (Dictionary dictionary : dictionaries) {
    for (int i = 0; i <= dictionary.getMaxId(); ++i) {
      values.add(dictionary.decodeToDouble(i));
    }
  }
  if (existingDict != null) {
    final NullableFloat8Vector existingDictValues = existingDict.getValueAccessorById(NullableFloat8Vector.class, 0).getValueVector();
    for (int i = 0; i < existingDict.getRecordCount(); ++i) {
      values.add(existingDictValues.getAccessor().get(i));
    }
  }
  final Iterator<Double> iter = values.iterator();
  int recordCount = 0;
  while (iter.hasNext()) {
    doubleVector.getMutator().setSafe(recordCount++, iter.next());
  }
  doubleVector.getMutator().setValueCount(recordCount);
  input.setRecordCount(recordCount);
  input.buildSchema(BatchSchema.SelectionVectorMode.NONE);
  return input;
}