| /* |
| * 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.quantiles; |
| |
| import static org.apache.datasketches.quantiles.PreambleUtil.COMBINED_BUFFER; |
| |
| import org.apache.datasketches.Family; |
| |
| /** |
| * This allows access to package-private levels and data in whatever quantiles sketch you give |
| * it: on-heap, off-heap; compact and non-compact |
| * @author Jon Malkin |
| */ |
| abstract class DoublesSketchAccessor extends DoublesBufferAccessor { |
| static final int BB_LVL_IDX = -1; |
| |
| final DoublesSketch ds_; |
| final boolean forceSize_; |
| |
| long n_; |
| int currLvl_; |
| int numItems_; |
| int offset_; |
| |
| DoublesSketchAccessor(final DoublesSketch ds, |
| final boolean forceSize, |
| final int level) { |
| ds_ = ds; |
| forceSize_ = forceSize; |
| |
| setLevel(level); |
| } |
| |
| static DoublesSketchAccessor wrap(final DoublesSketch ds) { |
| return wrap(ds, false); |
| } |
| |
| static DoublesSketchAccessor wrap(final DoublesSketch ds, |
| final boolean forceSize) { |
| |
| if (ds.isDirect()) { |
| return new DirectDoublesSketchAccessor(ds, forceSize, BB_LVL_IDX); |
| } |
| return new HeapDoublesSketchAccessor(ds, forceSize, BB_LVL_IDX); |
| } |
| |
| abstract DoublesSketchAccessor copyAndSetLevel(final int level); |
| |
| DoublesSketchAccessor setLevel(final int lvl) { |
| currLvl_ = lvl; |
| if (lvl == BB_LVL_IDX) { |
| numItems_ = (forceSize_ ? ds_.getK() * 2 : ds_.getBaseBufferCount()); |
| offset_ = (ds_.isDirect() ? COMBINED_BUFFER : 0); |
| } else { |
| assert lvl >= 0; |
| if (((ds_.getBitPattern() & (1L << lvl)) > 0) || forceSize_) { |
| numItems_ = ds_.getK(); |
| } else { |
| numItems_ = 0; |
| } |
| |
| // determine offset in two parts |
| // 1. index into combined buffer (compact vs update) |
| // 2. adjust if byte offset (direct) instead of array index (heap) |
| final int levelStart; |
| if (ds_.isCompact()) { |
| levelStart = ds_.getBaseBufferCount() + (countValidLevelsBelow(lvl) * ds_.getK()); |
| } else { |
| levelStart = (2 + currLvl_) * ds_.getK(); |
| } |
| |
| if (ds_.isDirect()) { |
| final int preLongsAndExtra = Family.QUANTILES.getMaxPreLongs() + 2; // +2 for min, max vals |
| offset_ = (preLongsAndExtra + levelStart) << 3; |
| } else { |
| offset_ = levelStart; |
| } |
| } |
| |
| n_ = ds_.getN(); |
| |
| return this; |
| } |
| |
| // getters/queries |
| |
| @Override |
| int numItems() { |
| return numItems_; |
| } |
| |
| @Override |
| abstract double get(final int index); |
| |
| @Override |
| abstract double[] getArray(final int fromIdx, final int numItems); |
| |
| // setters/modifying methods |
| |
| @Override |
| abstract double set(final int index, final double value); |
| |
| @Override |
| abstract void putArray(final double[] srcArray, final int srcIndex, |
| final int dstIndex, final int numItems); |
| |
| abstract void sort(); |
| |
| /** |
| * Counts number of full levels in the sketch below tgtLvl. Useful for computing the level |
| * offset in a compact sketch. |
| * @param tgtLvl Target level in the sketch |
| * @return Number of full levels in the sketch below tgtLvl |
| */ |
| private int countValidLevelsBelow(final int tgtLvl) { |
| int count = 0; |
| long bitPattern = ds_.getBitPattern(); |
| for (int i = 0; (i < tgtLvl) && (bitPattern > 0); ++i, bitPattern >>>= 1) { |
| if ((bitPattern & 1L) > 0L) { |
| ++count; |
| } |
| } |
| return count; |
| |
| // shorter implementation, testing suggests a tiny bit slower |
| //final long mask = (1 << tgtLvl) - 1; |
| //return Long.bitCount(ds_.getBitPattern() & mask); |
| } |
| } |