/*
* Druid - a distributed column store.
* Copyright (C) 2012, 2013 Metamarkets Group Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package io.druid.collections;
import java.nio.IntBuffer;
import java.util.ArrayList;
/**
*/
public class IntList
{
private final ArrayList<int[]> baseLists = new ArrayList<int[]>();
private final int allocateSize;
private int maxIndex;
public IntList()
{
this(1000);
}
public IntList(final int allocateSize)
{
this.allocateSize = allocateSize;
maxIndex = -1;
}
public int length()
{
return maxIndex + 1;
}
public boolean isEmpty()
{
return (length() == 0);
}
public void add(int value)
{
set(length(), value);
}
public void set(int index, int value)
{
int subListIndex = index / allocateSize;
if (subListIndex >= baseLists.size()) {
for (int i = baseLists.size(); i <= subListIndex; ++i) {
baseLists.add(null);
}
}
int[] baseList = baseLists.get(subListIndex);
if (baseList == null) {
baseList = new int[allocateSize];
baseLists.set(subListIndex, baseList);
}
baseList[index % allocateSize] = value;
if (index > maxIndex) {
maxIndex = index;
}
}
public int get(int index)
{
if (index > maxIndex) {
throw new ArrayIndexOutOfBoundsException(index);
}
int subListIndex = index / allocateSize;
int[] baseList = baseLists.get(subListIndex);
if (baseList == null) {
return 0;
}
return baseList[index % allocateSize];
}
public int baseListCount()
{
return baseLists.size();
}
public IntBuffer getBaseList(int index)
{
final int[] array = baseLists.get(index);
if (array == null) {
return null;
}
final IntBuffer retVal = IntBuffer.wrap(array);
if (index + 1 == baseListCount()) {
retVal.limit(maxIndex - (index * allocateSize));
}
return retVal.asReadOnlyBuffer();
}
public int[] toArray()
{
int[] retVal = new int[length()];
int currIndex = 0;
for (int[] arr : baseLists) {
int min = Math.min(length() - currIndex, arr.length);
System.arraycopy(arr, 0, retVal, currIndex, min);
currIndex += min;
}
return retVal;
}
}