FieldNode.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.arrow.flatbuf;

import com.google.flatbuffers.BaseVector;
import com.google.flatbuffers.BooleanVector;
import com.google.flatbuffers.ByteVector;
import com.google.flatbuffers.Constants;
import com.google.flatbuffers.DoubleVector;
import com.google.flatbuffers.FlatBufferBuilder;
import com.google.flatbuffers.FloatVector;
import com.google.flatbuffers.IntVector;
import com.google.flatbuffers.LongVector;
import com.google.flatbuffers.ShortVector;
import com.google.flatbuffers.StringVector;
import com.google.flatbuffers.Struct;
import com.google.flatbuffers.Table;
import com.google.flatbuffers.UnionVector;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;

/**
 * ----------------------------------------------------------------------
 * Data structures for describing a table row batch (a collection of
 * equal-length Arrow arrays)
 * Metadata about a field at some level of a nested type tree (but not
 * its children).
 *
 * For example, a List<Int16> with values `[[1, 2, 3], null, [4], [5, 6], null]`
 * would have {length: 5, null_count: 2} for its List node, and {length: 6,
 * null_count: 0} for its Int16 node, as separate FieldNode structs
 */
@SuppressWarnings("unused")
public final class FieldNode extends Struct {
  public void __init(int _i, ByteBuffer _bb) { __reset(_i, _bb); }
  public FieldNode __assign(int _i, ByteBuffer _bb) { __init(_i, _bb); return this; }

  /**
   * The number of value slots in the Arrow array at this level of a nested
   * tree
   */
  public long length() { return bb.getLong(bb_pos + 0); }
  /**
   * The number of observed nulls. Fields with null_count == 0 may choose not
   * to write their physical validity bitmap out as a materialized buffer,
   * instead setting the length of the bitmap buffer to 0.
   */
  public long nullCount() { return bb.getLong(bb_pos + 8); }

  public static int createFieldNode(FlatBufferBuilder builder, long length, long nullCount) {
    builder.prep(8, 16);
    builder.putLong(nullCount);
    builder.putLong(length);
    return builder.offset();
  }

  public static final class Vector extends BaseVector {
    public Vector __assign(int _vector, int _element_size, ByteBuffer _bb) { __reset(_vector, _element_size, _bb); return this; }

    public FieldNode get(int j) { return get(new FieldNode(), j); }
    public FieldNode get(FieldNode obj, int j) {  return obj.__assign(__element(j), bb); }
  }
}