core/src/main/java/org/apache/carbondata/core/datastore/page/encoding/EncodedColumnPage.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.carbondata.core.datastore.page.encoding;

import java.nio.ByteBuffer;

import org.apache.carbondata.core.datastore.page.ColumnPage;
import org.apache.carbondata.core.datastore.page.LocalDictColumnPage;
import org.apache.carbondata.core.datastore.page.statistics.SimpleStatsResult;
import org.apache.carbondata.core.localdictionary.PageLevelDictionary;
import org.apache.carbondata.core.memory.UnsafeMemoryManager;
import org.apache.carbondata.core.util.CarbonUtil;
import org.apache.carbondata.format.DataChunk2;

/**
 * An column page after encoding.
 */
public class EncodedColumnPage {

  // encoded and compressed column page data
  protected final ByteBuffer encodedData;

  // metadata of this page
  private DataChunk2 pageMetadata;

  private ColumnPage actualPage;

  /**
   * Constructor
   * @param pageMetadata metadata of the encoded page
   * @param encodedData encoded data for this page
   */
  public EncodedColumnPage(DataChunk2 pageMetadata, ByteBuffer encodedData,
      ColumnPage actualPage) {
    if (pageMetadata == null) {
      throw new IllegalArgumentException("data chunk2 must not be null");
    }
    if (encodedData == null) {
      throw new IllegalArgumentException("encoded data must not be null");
    }
    this.pageMetadata = pageMetadata;
    this.encodedData = encodedData;
    this.actualPage = actualPage;
  }

  /**
   * return the encoded data as ByteBuffer
   */
  public ByteBuffer getEncodedData() {
    return encodedData;
  }

  public DataChunk2 getPageMetadata() {
    return pageMetadata;
  }

  /**
   * Return the total size of serialized data and metadata
   */
  public int getTotalSerializedSize() {
    int metadataSize = CarbonUtil.getByteArray(pageMetadata).length;
    int dataSize = encodedData.limit() - encodedData.position();
    return metadataSize + dataSize;
  }

  public SimpleStatsResult getStats() {
    return actualPage.getStatistics();
  }

  public ColumnPage getActualPage() {
    return actualPage;
  }

  public boolean isLocalDictGeneratedPage() {
    return actualPage.isLocalDictGeneratedPage();
  }

  public PageLevelDictionary getPageDictionary() {
    return actualPage.getColumnPageDictionary();
  }

  public void freeMemory() {
    if (actualPage instanceof LocalDictColumnPage) {
      LocalDictColumnPage page = (LocalDictColumnPage) actualPage;
      page.freeMemoryForce();
    }
  }

  public void cleanBuffer() {
    UnsafeMemoryManager.destroyDirectByteBuffer(encodedData);
  }
}