org.apache.lucene.util.MapOfSets Maven / Gradle / Ivy
/*
* 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.util;
import java.util.Set;
import java.util.Collection;
import java.util.HashSet;
import java.util.Map;
/**
* Helper class for keeping Lists of Objects associated with keys. WARNING: THIS CLASS IS NOT THREAD SAFE
* @lucene.internal
*/
public class MapOfSets {
private final Map> theMap;
/**
* @param m the backing store for this object
*/
public MapOfSets(Map> m) {
theMap = m;
}
/**
* @return direct access to the map backing this object.
*/
public Map> getMap() {
return theMap;
}
/**
* Adds val to the Set associated with key in the Map. If key is not
* already in the map, a new Set will first be created.
* @return the size of the Set associated with key once val is added to it.
*/
public int put(K key, V val) {
final Set theSet;
if (theMap.containsKey(key)) {
theSet = theMap.get(key);
} else {
theSet = new HashSet<>(23);
theMap.put(key, theSet);
}
theSet.add(val);
return theSet.size();
}
/**
* Adds multiple vals to the Set associated with key in the Map.
* If key is not
* already in the map, a new Set will first be created.
* @return the size of the Set associated with key once val is added to it.
*/
public int putAll(K key, Collection vals) {
final Set theSet;
if (theMap.containsKey(key)) {
theSet = theMap.get(key);
} else {
theSet = new HashSet<>(23);
theMap.put(key, theSet);
}
theSet.addAll(vals);
return theSet.size();
}
}