content: /*
   * 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.memory;
  
  import org.apache.carbondata.common.logging.LogServiceFactory;
  
  import org.apache.log4j.Logger;
  
  /**
   * Holds the pointers for rows.
   */
  public class IntPointerBuffer {
  
    private static final Logger LOGGER =
        LogServiceFactory.getLogService(IntPointerBuffer.class.getName());
  
    private int length;
  
    private int actualSize;
  
    private int[] pointerBlock;
  
    private MemoryBlock pointerMemoryBlock;
  
    private String taskId;
  
    public IntPointerBuffer(String taskId) {
      // TODO can be configurable, it is initial size and it can grow automatically.
      this.length = 100000;
      pointerBlock = new int[length];
      this.taskId = taskId;
    }
  
    public IntPointerBuffer(int length) {
      this.length = length;
      pointerBlock = new int[length];
    }
  
    public void set(int rowId, int value) {
      pointerBlock[rowId] = value;
    }
  
    public void set(int value) {
      ensureMemory();
      pointerBlock[actualSize] = value;
      actualSize++;
    }
  
    /**
     * Returns the value at position {@code rowId}.
     */
    public int get(int rowId) {
      assert rowId >= 0 : "rowId (" + rowId + ") should >= 0";
      assert rowId < length : "rowId (" + rowId + ") should < length (" + length + ")";
      if (pointerBlock == null) {
        return CarbonUnsafe.getUnsafe().getInt(pointerMemoryBlock.getBaseObject(),
            pointerMemoryBlock.getBaseOffset() + (rowId << 2));
      }
      return pointerBlock[rowId];
    }
  
    public void loadToUnsafe() {
      pointerMemoryBlock =
          UnsafeSortMemoryManager.INSTANCE.allocateMemory(this.taskId, pointerBlock.length * 4);
      // pointerMemoryBlock it means sort storage memory manager does not have space to loaf pointer
      // buffer in that case use pointerBlock
      if (null != pointerMemoryBlock) {
        for (int i = 0; i < pointerBlock.length; i++) {
          CarbonUnsafe.getUnsafe()
              .putInt(pointerMemoryBlock.getBaseObject(), pointerMemoryBlock.getBaseOffset() + i * 4,
                  pointerBlock[i]);
        }
        pointerBlock = null;
      }
    }
  
    public int getActualSize() {
      return actualSize;
    }
  
    public int[] getPointerBlock() {
      return pointerBlock;
    }
  
    private void ensureMemory() {
      if (actualSize >= length) {
        // Expand by quarter, may be we can correct the logic later
        int localLength = length + (int) (length * (0.25));
        int[] memoryAddress = new int[localLength];
        System.arraycopy(pointerBlock, 0, memoryAddress, 0, length);
        pointerBlock = memoryAddress;
        length = localLength;
      }
    }
  
    public void freeMemory() {
      pointerBlock = null;
      if (pointerMemoryBlock != null) {
        UnsafeSortMemoryManager.INSTANCE.freeMemory(this.taskId, pointerMemoryBlock);
      }
    }
  }