public static TypeReader createTreeReader()

in java/core/src/java/org/apache/orc/impl/TreeReaderFactory.java [2976:3043]
65 lines of code
28 McCabe index (conditional complexity)

  public static TypeReader createTreeReader(TypeDescription readerType,
                                            Context context) throws IOException {
    OrcFile.Version version = context.getFileFormat();
    final SchemaEvolution evolution = context.getSchemaEvolution();
    TypeDescription fileType = evolution.getFileType(readerType);
    if (fileType == null || !evolution.includeReaderColumn(readerType.getId())){
      return new NullTreeReader(-1, context);
    }
    TypeDescription.Category readerTypeCategory = readerType.getCategory();
    // We skip attribute checks when comparing types since they are not used to
    // create the ConvertTreeReaders
    if (!fileType.equals(readerType, false) &&
        (readerTypeCategory != TypeDescription.Category.STRUCT &&
         readerTypeCategory != TypeDescription.Category.MAP &&
         readerTypeCategory != TypeDescription.Category.LIST &&
         readerTypeCategory != TypeDescription.Category.UNION)) {
      // We only convert complex children.
      return ConvertTreeReaderFactory.createConvertTreeReader(readerType, context);
    }
    switch (readerTypeCategory) {
      case BOOLEAN:
        return new BooleanTreeReader(fileType.getId(), context);
      case BYTE:
        return new ByteTreeReader(fileType.getId(), context);
      case DOUBLE:
        return new DoubleTreeReader(fileType.getId(), context);
      case FLOAT:
        return new FloatTreeReader(fileType.getId(), context);
      case SHORT:
        return new ShortTreeReader(fileType.getId(), context);
      case INT:
        return new IntTreeReader(fileType.getId(), context);
      case LONG:
        return new LongTreeReader(fileType.getId(), context);
      case STRING:
        return new StringTreeReader(fileType.getId(), context);
      case CHAR:
        return new CharTreeReader(fileType.getId(), readerType.getMaxLength(), context);
      case VARCHAR:
        return new VarcharTreeReader(fileType.getId(), readerType.getMaxLength(), context);
      case BINARY:
        return new BinaryTreeReader(fileType.getId(), context);
      case TIMESTAMP:
        return new TimestampTreeReader(fileType.getId(), context, false);
      case TIMESTAMP_INSTANT:
        return new TimestampTreeReader(fileType.getId(), context, true);
      case DATE:
        return new DateTreeReader(fileType.getId(), context);
      case DECIMAL:
        if (isDecimalAsLong(version, fileType.getPrecision())){
          return new Decimal64TreeReader(fileType.getId(), fileType.getPrecision(),
              fileType.getScale(), context);
        }
        return new DecimalTreeReader(fileType.getId(), fileType.getPrecision(),
            fileType.getScale(), context);
      case STRUCT:
        return new StructTreeReader(fileType.getId(), readerType, context);
      case LIST:
        return new ListTreeReader(fileType.getId(), readerType, context);
      case MAP:
        return new MapTreeReader(fileType.getId(), readerType, context);
      case UNION:
        return new UnionTreeReader(fileType.getId(), readerType, context);
      default:
        throw new IllegalArgumentException("Unsupported type " +
            readerTypeCategory);
    }
  }