Class Factory

java/core/src/java/org/apache/orc/impl/writer/TreeWriter.java:114–196

  void getCurrentStatistics(ColumnStatistics[] output);

  class Factory {
    /**
     * Create a new tree writer for the given types and insert encryption if
     * required.
     * @param schema the type to build a writer for
     * @param encryption the encryption status
     * @param streamFactory the writer context
     * @return a new tree writer
     */
    public static TreeWriter create(TypeDescription schema,
                                    WriterEncryptionVariant encryption,
                                    WriterContext streamFactory) throws IOException {
      if (encryption == null) {
        // If we are the root of an encryption variant, create a special writer.
        encryption = streamFactory.getEncryption(schema.getId());
        if (encryption != null) {
          return new EncryptionTreeWriter(schema, encryption, streamFactory);
        }
      }
      return createSubtree(schema, encryption, streamFactory);
    }

    /**
     * Create a subtree without inserting encryption nodes
     * @param schema the schema to create
     * @param encryption the encryption variant
     * @param streamFactory the writer context
     * @return a new tree writer
     */
    static TreeWriter createSubtree(TypeDescription schema,
                                    WriterEncryptionVariant encryption,
                                    WriterContext streamFactory) throws IOException {
      OrcFile.Version version = streamFactory.getVersion();
      switch (schema.getCategory()) {
        case BOOLEAN:
          return new BooleanTreeWriter(schema, encryption, streamFactory);
        case BYTE:
          return new ByteTreeWriter(schema, encryption, streamFactory);
        case SHORT:
        case INT:
        case LONG:
          return new IntegerTreeWriter(schema, encryption, streamFactory);
        case FLOAT:
          return new FloatTreeWriter(schema, encryption, streamFactory);
        case DOUBLE:
          return new DoubleTreeWriter(schema, encryption, streamFactory);
        case STRING:
          return new StringTreeWriter(schema, encryption, streamFactory);
        case CHAR:
          return new CharTreeWriter(schema, encryption, streamFactory);
        case VARCHAR:
          return new VarcharTreeWriter(schema, encryption, streamFactory);
        case BINARY:
          return new BinaryTreeWriter(schema, encryption, streamFactory);
        case TIMESTAMP:
          return new TimestampTreeWriter(schema, encryption, streamFactory, false);
        case TIMESTAMP_INSTANT:
          return new TimestampTreeWriter(schema, encryption, streamFactory, true);