| /* |
| * 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.datasketches.tuple; |
| |
| import static java.lang.Math.ceil; |
| import static java.lang.Math.max; |
| import static java.lang.Math.min; |
| import static org.apache.datasketches.HashOperations.hashInsertOnly; |
| import static org.apache.datasketches.HashOperations.hashSearch; |
| import static org.apache.datasketches.Util.MIN_LG_NOM_LONGS; |
| import static org.apache.datasketches.Util.ceilingPowerOf2; |
| |
| import java.lang.reflect.Array; |
| |
| @SuppressWarnings("unchecked") |
| class HashTables<S extends Summary> { |
| long[] hashTable_ = null; |
| S[] summaryTable_ = null; |
| int lgTableSize_ = 0; |
| int count_ = 0; |
| |
| HashTables() { } |
| |
| //must have valid entries |
| void fromSketch(final Sketch<S> sketch) { |
| count_ = sketch.getRetainedEntries(); |
| lgTableSize_ = getLgTableSize(count_); |
| |
| hashTable_ = new long[1 << lgTableSize_]; |
| final SketchIterator<S> it = sketch.iterator(); |
| while (it.next()) { |
| final long hash = it.getHash(); |
| final int index = hashInsertOnly(hashTable_, lgTableSize_, hash); |
| final S mySummary = (S)it.getSummary().copy(); |
| if (summaryTable_ == null) { |
| summaryTable_ = (S[]) Array.newInstance(mySummary.getClass(), 1 << lgTableSize_); |
| } |
| summaryTable_[index] = mySummary; |
| } |
| } |
| |
| //must have valid entries |
| void fromSketch(final org.apache.datasketches.theta.Sketch sketch, final S summary) { |
| count_ = sketch.getRetainedEntries(true); |
| lgTableSize_ = getLgTableSize(count_); |
| |
| hashTable_ = new long[1 << lgTableSize_]; |
| final org.apache.datasketches.theta.HashIterator it = sketch.iterator(); |
| while (it.next()) { |
| final long hash = it.get(); |
| final int index = hashInsertOnly(hashTable_, lgTableSize_, hash); |
| final S mySummary = (S)summary.copy(); |
| if (summaryTable_ == null) { |
| summaryTable_ = (S[]) Array.newInstance(mySummary.getClass(), 1 << lgTableSize_); |
| } |
| summaryTable_[index] = mySummary; |
| } |
| } |
| |
| private void fromArrays(final long[] hashArr, final S[] summaryArr, final int count) { |
| count_ = count; |
| lgTableSize_ = getLgTableSize(count); |
| |
| summaryTable_ = null; |
| hashTable_ = new long[1 << lgTableSize_]; |
| for (int i = 0; i < count; i++) { |
| final long hash = hashArr[i]; |
| final int index = hashInsertOnly(hashTable_, lgTableSize_, hash); |
| final S mySummary = summaryArr[i]; |
| if (summaryTable_ == null) { |
| summaryTable_ = (S[]) Array.newInstance(mySummary.getClass(), 1 << lgTableSize_); |
| } |
| summaryTable_[index] = summaryArr[i]; |
| } |
| } |
| |
| //For Tuple Sketches |
| HashTables<S> getIntersectHashTables( |
| final Sketch<S> nextTupleSketch, |
| final long thetaLong, |
| final SummarySetOperations<S> summarySetOps) { |
| |
| final Class<S> summaryType = (Class<S>) summaryTable_.getClass().getComponentType(); |
| |
| //Match nextSketch data with local instance data, filtering by theta |
| final int maxMatchSize = min(count_, nextTupleSketch.getRetainedEntries()); |
| final long[] matchHashArr = new long[maxMatchSize]; |
| final S[] matchSummariesArr = (S[]) Array.newInstance(summaryType, maxMatchSize); |
| int matchCount = 0; |
| final SketchIterator<S> it = nextTupleSketch.iterator(); |
| |
| while (it.next()) { |
| final long hash = it.getHash(); |
| if (hash >= thetaLong) { continue; } |
| final int index = hashSearch(hashTable_, lgTableSize_, hash); |
| if (index < 0) { continue; } |
| //Copy the intersecting items from local hashTables_ |
| // sequentially into local matchHashArr_ and matchSummaries_ |
| matchHashArr[matchCount] = hash; |
| matchSummariesArr[matchCount] = summarySetOps.intersection(summaryTable_[index], it.getSummary()); |
| matchCount++; |
| } |
| final HashTables<S> resultHT = new HashTables<>(); |
| resultHT.fromArrays(matchHashArr, matchSummariesArr, matchCount); |
| return resultHT; |
| } |
| |
| //For Theta Sketches |
| HashTables<S> getIntersectHashTables( |
| final org.apache.datasketches.theta.Sketch nextThetaSketch, |
| final long thetaLong, |
| final SummarySetOperations<S> summarySetOps, |
| final S summary) { |
| |
| final Class<S> summaryType = (Class<S>) summary.getClass(); |
| |
| //Match nextSketch data with local instance data, filtering by theta |
| final int maxMatchSize = min(count_, nextThetaSketch.getRetainedEntries()); |
| final long[] matchHashArr = new long[maxMatchSize]; |
| final S[] matchSummariesArr = (S[]) Array.newInstance(summaryType, maxMatchSize); |
| int matchCount = 0; |
| final org.apache.datasketches.theta.HashIterator it = nextThetaSketch.iterator(); |
| |
| //scan B & search A(hashTable) for match |
| while (it.next()) { |
| final long hash = it.get(); |
| if (hash >= thetaLong) { continue; } |
| final int index = hashSearch(hashTable_, lgTableSize_, hash); |
| if (index < 0) { continue; } |
| //Copy the intersecting items from local hashTables_ |
| // sequentially into local matchHashArr_ and matchSummaries_ |
| matchHashArr[matchCount] = hash; |
| matchSummariesArr[matchCount] = summarySetOps.intersection(summaryTable_[index], summary); |
| matchCount++; |
| } |
| final HashTables<S> resultHT = new HashTables<>(); |
| resultHT.fromArrays(matchHashArr, matchSummariesArr, matchCount); |
| return resultHT; |
| } |
| |
| void clear() { |
| hashTable_ = null; |
| summaryTable_ = null; |
| lgTableSize_ = 0; |
| count_ = 0; |
| } |
| |
| static int getLgTableSize(final int count) { |
| final int tableSize = max(ceilingPowerOf2((int) ceil(count / 0.75)), 1 << MIN_LG_NOM_LONGS); |
| return Integer.numberOfTrailingZeros(tableSize); |
| } |
| |
| } |