Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright 2004-2012 the Seasar Foundation and the Others.
 *
 * 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 {

    public static <K, V> V putIfAbsent(final ConcurrentMap<K, V> map, final K key, final V value) {
        final V exists = map.putIfAbsent(key, value);
        if (exists != null) {
            return exists;
        }
        return value;
    }
}