Java ConcurrentMap remove(K key, ConcurrentMap map, Object value)

Description

remove

License

Apache License

Return

if entry removed return 0. if replace old entry return 1, if value not exist return -1;

Declaration

public static <K> int remove(K key, ConcurrentMap<K, Object[]> map, Object value) 

Method Source Code

//package com.java2s;
/*//from  w ww . jav a2  s. co  m
 * Copyright 2009 zaichu xiao
 *
 * 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 {
    /**
     * @return if entry removed return 0. if replace old entry return 1, if
     *         value not exist return -1;
     * 
     */
    public static <K> int remove(K key, ConcurrentMap<K, Object[]> map, Object value) {
        outer: for (;;) {
            Object[] elements = map.get(key);
            if (elements != null) {
                int i, len = i = elements.length;
                while (--i >= 0) {
                    if (value.equals(elements[i])) {
                        if (--len > 0) {
                            Object[] newElements = new Object[len];
                            while (--len >= i)
                                newElements[len] = elements[len + 1];
                            while (--i >= 0)
                                newElements[i] = elements[i];
                            if (map.replace(key, elements, newElements))
                                return 1;
                        } else if (map.remove(key, elements))
                            return 0;
                        continue outer;
                    }
                }
            }
            return -1;
        }
    }
}

Related

1. putIfAbsent(ConcurrentMap map, K key, V value)
2. putIfAbsent(ConcurrentMap target, K key, V value)
3. putIfAbsent(final ConcurrentMap map, final K key, final V value)
4. putIfAbsentAndGet(ConcurrentMap map, K key, V newValue)
5. remove(ConcurrentMap map, K key, V value)
6. removeFromContainedSet(ConcurrentMap> map, K mapKey, V value)