| /* |
| * 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.lucene.luke.models.overview; |
| |
| import java.io.IOException; |
| import java.util.Comparator; |
| import java.util.LinkedHashMap; |
| import java.util.Map; |
| import java.util.Objects; |
| import java.util.stream.Collectors; |
| |
| import org.apache.lucene.index.IndexReader; |
| import org.apache.lucene.luke.models.util.IndexUtils; |
| |
| /** |
| * An utility class that collects term counts terms for all fields in a index. |
| */ |
| final class TermCounts { |
| |
| private final Map<String, Long> termCountMap; |
| |
| TermCounts(IndexReader reader) throws IOException { |
| Objects.requireNonNull(reader); |
| termCountMap = IndexUtils.countTerms(reader, IndexUtils.getFieldNames(reader)); |
| } |
| |
| /** |
| * Returns the total number of terms in this index. |
| */ |
| long numTerms() { |
| return termCountMap.values().stream().mapToLong(Long::longValue).sum(); |
| } |
| |
| /** |
| * Returns all fields with the number of terms for each field sorted by {@link TermCountsOrder} |
| * @param order - sort order |
| */ |
| Map<String, Long> sortedTermCounts(TermCountsOrder order){ |
| Objects.requireNonNull(order); |
| |
| Comparator<Map.Entry<String, Long>> comparator; |
| switch (order) { |
| case NAME_ASC: |
| comparator = Map.Entry.comparingByKey(); |
| break; |
| case NAME_DESC: |
| comparator = Map.Entry.<String, Long>comparingByKey().reversed(); |
| break; |
| case COUNT_ASC: |
| comparator = Map.Entry.comparingByValue(); |
| break; |
| case COUNT_DESC: |
| comparator = Map.Entry.<String, Long>comparingByValue().reversed(); |
| break; |
| default: |
| comparator = Map.Entry.comparingByKey(); |
| } |
| return sortedTermCounts(comparator); |
| } |
| |
| private Map<String, Long> sortedTermCounts(Comparator<Map.Entry<String, Long>> comparator) { |
| return termCountMap.entrySet().stream() |
| .sorted(comparator) |
| .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue, (v1, v2) -> v1, LinkedHashMap::new)); |
| } |
| |
| } |