| /* |
| * 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.req; |
| |
| import java.util.List; |
| |
| /** |
| * Iterator over all retained items of the ReqSketch. The order is not defined. |
| * |
| * @author Lee Rhodes |
| */ |
| public class ReqIterator { |
| private List<ReqCompactor> compactors; |
| private int cIndex; |
| private int bIndex; |
| private int retainedItems; |
| private int count; |
| private FloatBuffer currentBuf; |
| |
| ReqIterator(final ReqSketch sketch) { |
| compactors = sketch.getCompactors(); |
| retainedItems = sketch.getRetainedItems(); |
| currentBuf = compactors.get(0).getBuffer(); |
| cIndex = 0; |
| bIndex = -1; |
| count = 0; |
| } |
| |
| /** |
| * Advancing the iterator and checking existence of the next entry |
| * is combined here for efficiency. This results in an undefined |
| * state of the iterator before the first call of this method. |
| * @return true if the next element exists |
| */ |
| public boolean next() { |
| if ((retainedItems == 0) |
| || ((cIndex == (compactors.size() - 1)) && (bIndex == (currentBuf.getCount() - 1)))) { |
| return false; |
| } |
| if (bIndex == (currentBuf.getCount() - 1)) { |
| cIndex++; |
| currentBuf = compactors.get(cIndex).getBuffer(); |
| bIndex = 0; |
| } else { |
| bIndex++; |
| } |
| count++; |
| return true; |
| } |
| |
| /** |
| * Gets a value from the current entry in the sketch. |
| * Don't call this before calling next() for the first time |
| * or after getting false from next(). |
| * @return value from the current entry |
| */ |
| public float getValue() { |
| return currentBuf.getItem(bIndex); |
| } |
| |
| /** |
| * Gets a weight for the value from the current entry in the sketch. |
| * Don't call this before calling next() for the first time |
| * or after getting false from next(). |
| * @return weight for the value from the current entry |
| */ |
| public long getWeight() { |
| return 1 << cIndex; |
| } |
| |
| /** |
| * The number of items processed so far |
| * @return The number of items processed so far |
| */ |
| public int getCount() { |
| return count; |
| } |
| } |