Java ConcurrentMap putIfAbsent(final ConcurrentMap map, final K key, final V value)

Description

put If Absent

License

Apache License

Parameter

Parameter	Description
K	a parameter
V	a parameter
map	a parameter
key	a parameter
value	a parameter

Declaration

public static <K, V> V putIfAbsent(final ConcurrentMap<K, V> map,
        final K key, final V value) 

Method Source Code

//package com.java2s;
/*/*w  w w .ja  va2  s . c om*/
 * Copyright 2015-2016 the original author or authors.
 *
 * Licensed 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.
 */

import java.util.concurrent.ConcurrentMap;

public class Main {
    /**
     * @param <K>
     * @param <V>
     * @param map
     * @param key
     * @param value
     * @return 
     * @see ConcurrentHashMap#putIfAbsent(Object, Object)
     */
    public static <K, V> V putIfAbsent(final ConcurrentMap<K, V> map,
            final K key, final V value) {
        V exists = map.putIfAbsent(key, value);
        if (exists != null) {
            return exists;
        }
        return value;
    }
}

Related

1. isClassClass(Class clazz)
2. putIfAbsent(ConcurrentMap map, K key, V value)
3. putIfAbsent(ConcurrentMap map, K key, V value)
4. putIfAbsent(ConcurrentMap map, K key, V value)
5. putIfAbsent(ConcurrentMap target, K key, V value)
6. putIfAbsentAndGet(ConcurrentMap map, K key, V newValue)
7. remove(ConcurrentMap map, K key, V value)
8. remove(K key, ConcurrentMap map, Object value)
9. removeFromContainedSet(ConcurrentMap> map, K mapKey, V value)