Java Map Put putOrCreateList(Map> map, K key, V value)

Description

put Or Create List

License

Open Source License

Declaration

public static <K, V> void putOrCreateList(Map<K, List<V>> map, K key, V value) 

Method Source Code

//package com.java2s;
/**/* w w  w .j  a  va 2  s  . co m*/
 * This file is part of SADL, a library for learning all sorts of (timed) automata and performing sequence-based anomaly detection.
 * Copyright (C) 2013-2016  the original author or authors.
 *
 * SADL is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * SADL is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with SADL.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

public class Main {
    public static <K, V> void putOrCreateList(Map<K, List<V>> map, K key, V value) {
        List<V> list;
        list = map.get(key);
        if (list == null) {
            list = new ArrayList<>();
            list.add(value);
            map.put(key, list);
        } else {
            list.add(value);
        }
    }
}

Related

1. putMultiEntry(Map map, Iterable keys, V value)
2. putMultiple(Map map, Object key, Object value)
3. putNotDup(Map tbl, String key, String value)
4. putObject(Map map, V key, W value)
5. putObjectsInMultiMap(Map>> multiMap, Integer key, List stringPair)
6. putOrRemove(Map map, String key, Object obj)
7. putPairs(Map map, Object... pairs)
8. putParameter(String key, String value, Map map)
9. putPreferenceStoredMapValue(String keyOfPreference, String keyInMap, Object value)