CountDownFuture.java

/**
 * 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.
 */
package io.horizondb.db.util.concurrent;

import java.util.concurrent.atomic.AtomicLong;

import com.google.common.util.concurrent.AbstractFuture;

/**
 * @author Benjamin
 *
 */
public final class CountDownFuture<V> extends AbstractFuture<V> {

    private final V value;
    
    private final AtomicLong count;

    /**
     * @param value
     * @param latch
     */
    public CountDownFuture(V value, int count) {
        this.value = value;
        this.count = new AtomicLong(count);
    }

    public void countDown() {
        if (this.count.addAndGet(-1) == 0) {
            set(this.value);
        }
    }

    
}