org.apache.druid.frame.field.NumericArrayFieldReader Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of druid-processing Show documentation

A module that is everything required to understands Druid Segments

There is a newer version: 30.0.1

/*
 * 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.druid.frame.field;

import org.apache.datasketches.memory.Memory;
import org.apache.druid.error.DruidException;
import org.apache.druid.query.extraction.ExtractionFn;
import org.apache.druid.segment.DimensionSelector;

import javax.annotation.Nullable;

/**
 * Reader class for the fields written by {@link NumericArrayFieldWriter}. See the Javadoc for the writer for more
 * information on the format
 *
 * The numeric array fields are byte comparable
 */
public abstract class NumericArrayFieldReader implements FieldReader
{
  @Override
  public DimensionSelector makeDimensionSelector(
      Memory memory,
      ReadableFieldPointer fieldPointer,
      @Nullable ExtractionFn extractionFn
  )
  {
    throw DruidException.defensive("Cannot call makeDimensionSelector on field of type ARRAY");
  }

  @Override
  public boolean isNull(Memory memory, long position)
  {
    final byte firstByte = memory.getByte(position);
    return firstByte == NumericArrayFieldWriter.NULL_ROW;
  }

  @Override
  public boolean isComparable()
  {
    return true;
  }
}