| /* |
| * 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; |
| |
| /** |
| * Iterator over a generic tuple sketch |
| * @param <S> Type of Summary |
| */ |
| public class SketchIterator<S extends Summary> { |
| |
| private long[] keys_; |
| private S[] summaries_; |
| private int i_; |
| |
| SketchIterator(final long[] keys, final S[] summaries) { |
| keys_ = keys; |
| summaries_ = summaries; |
| i_ = -1; |
| } |
| |
| /** |
| * 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 (keys_ == null) { return false; } |
| i_++; |
| while (i_ < keys_.length) { |
| if (keys_[i_] != 0) { return true; } |
| i_++; |
| } |
| return false; |
| } |
| |
| /** |
| * Gets a key from the current entry in the sketch, which is a hash |
| * of the original key passed to update(). The original keys are not |
| * retained. Don't call this before calling next() for the first time |
| * or after getting false from next(). |
| * @return hash key from the current entry |
| */ |
| public long getKey() { |
| return keys_[i_]; |
| } |
| |
| /** |
| * Gets a Summary object 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 Summary object for the current entry (this is not a copy!) |
| */ |
| public S getSummary() { |
| return summaries_[i_]; |
| } |
| |
| } |