1 package org.apache.lucene.facet.taxonomy.writercache.lru;
3 import org.apache.lucene.facet.taxonomy.CategoryPath;
6 * Licensed to the Apache Software Foundation (ASF) under one or more
7 * contributor license agreements. See the NOTICE file distributed with
8 * this work for additional information regarding copyright ownership.
9 * The ASF licenses this file to You under the Apache License, Version 2.0
10 * (the "License"); you may not use this file except in compliance with
11 * the License. You may obtain a copy of the License at
13 * http://www.apache.org/licenses/LICENSE-2.0
15 * Unless required by applicable law or agreed to in writing, software
16 * distributed under the License is distributed on an "AS IS" BASIS,
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18 * See the License for the specific language governing permissions and
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23 * An an LRU cache of mapping from name to int.
24 * Used to cache Ordinals of category paths.
25 * It uses as key, hash of the path instead of the path.
26 * This way the cahce takes less RAM, but correctness depends on
27 * assuming no collisions.
29 * @lucene.experimental
31 public class NameHashIntCacheLRU extends NameIntCacheLRU {
33 NameHashIntCacheLRU(int maxCacheSize) {
38 Object key(CategoryPath name) {
39 return new Long(name.longHashCode());
43 Object key(CategoryPath name, int prefixLen) {
44 return new Long(name.longHashCode(prefixLen));