| /* |
| * Copyright 2009-2010 by The Regents of the University of California |
| * Licensed 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 from |
| * |
| * 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 edu.uci.ics.hyracks.storage.am.lsm.invertedindex.search; |
| |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| |
| import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.api.IInvertedListCursor; |
| import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.api.IObjectFactory; |
| import edu.uci.ics.hyracks.storage.am.lsm.invertedindex.util.ObjectCache; |
| |
| public class InvertedListPartitions { |
| private final int DEFAULT_NUM_PARTITIONS = 10; |
| private final int PARTITIONS_SLACK_SIZE = 10; |
| private final int OBJECT_CACHE_INIT_SIZE = 10; |
| private final int OBJECT_CACHE_EXPAND_SIZE = 10; |
| private final IObjectFactory<ArrayList<IInvertedListCursor>> arrayListFactory; |
| private final ObjectCache<ArrayList<IInvertedListCursor>> arrayListCache; |
| private ArrayList<IInvertedListCursor>[] partitions; |
| private short minValidPartitionIndex; |
| private short maxValidPartitionIndex; |
| |
| public InvertedListPartitions() { |
| this.arrayListFactory = new ArrayListFactory<IInvertedListCursor>(); |
| this.arrayListCache = new ObjectCache<ArrayList<IInvertedListCursor>>(arrayListFactory, OBJECT_CACHE_INIT_SIZE, |
| OBJECT_CACHE_EXPAND_SIZE); |
| } |
| |
| @SuppressWarnings("unchecked") |
| public void reset(short numTokensLowerBound, short numTokensUpperBound) { |
| if (partitions == null) { |
| int initialSize; |
| if (numTokensUpperBound < 0) { |
| initialSize = DEFAULT_NUM_PARTITIONS; |
| } else { |
| initialSize = numTokensUpperBound + 1; |
| } |
| partitions = (ArrayList<IInvertedListCursor>[]) new ArrayList[initialSize]; |
| } else { |
| if (numTokensUpperBound + 1 >= partitions.length) { |
| partitions = Arrays.copyOf(partitions, numTokensUpperBound + 1); |
| } |
| Arrays.fill(partitions, null); |
| } |
| arrayListCache.reset(); |
| minValidPartitionIndex = Short.MAX_VALUE; |
| maxValidPartitionIndex = Short.MIN_VALUE; |
| } |
| |
| public void addInvertedListCursor(IInvertedListCursor listCursor, short numTokens) { |
| if (numTokens + 1 >= partitions.length) { |
| partitions = Arrays.copyOf(partitions, numTokens + PARTITIONS_SLACK_SIZE); |
| } |
| ArrayList<IInvertedListCursor> partitionCursors = partitions[numTokens]; |
| if (partitionCursors == null) { |
| partitionCursors = arrayListCache.getNext(); |
| partitionCursors.clear(); |
| partitions[numTokens] = partitionCursors; |
| // Update range of valid partitions. |
| if (numTokens < minValidPartitionIndex) { |
| minValidPartitionIndex = numTokens; |
| } |
| if (numTokens > maxValidPartitionIndex) { |
| maxValidPartitionIndex = numTokens; |
| } |
| } |
| partitionCursors.add(listCursor); |
| } |
| |
| public ArrayList<IInvertedListCursor>[] getPartitions() { |
| return partitions; |
| } |
| |
| public short getMinValidPartitionIndex() { |
| return minValidPartitionIndex; |
| } |
| |
| public short getMaxValidPartitionIndex() { |
| return maxValidPartitionIndex; |
| } |
| } |