org.apache.usergrid.persistence.collection.uniquevalues.ReservationCache.java Source code

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Here is the source code for org.apache.usergrid.persistence.collection.uniquevalues.ReservationCache.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.usergrid.persistence.collection.uniquevalues;

import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheStats;
import org.apache.usergrid.persistence.actorsystem.ClientActor;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.concurrent.TimeUnit;

public class ReservationCache {
    private static final Logger logger = LoggerFactory.getLogger(ClientActor.class);

    Cache<String, UniqueValueActor.Reservation> cache;
    long ttl;

    // use hokey old-style singleton because its not that easy to get Guice into an actor
    private static ReservationCache instance = null;

    ReservationCache(long ttl) {
        this.ttl = ttl;
        cache = CacheBuilder.newBuilder().maximumSize(1000).concurrencyLevel(300)
                .expireAfterWrite(ttl, TimeUnit.SECONDS).recordStats().build();
    }

    public static void init(long ttl) {
        instance = new ReservationCache(ttl);
    }

    public static ReservationCache getInstance() {
        if (instance == null) {
            throw new IllegalStateException("ReservationCache not initialized yet");
        }
        return instance;
    }

    public UniqueValueActor.Reservation get(String rowKey) {
        if (ttl == 0) {
            return null;
        }
        UniqueValueActor.Reservation res = cache.getIfPresent(rowKey);
        return res;
    }

    public void cacheReservation(UniqueValueActor.Reservation reservation) {
        if (ttl == 0) {
            return;
        }
        cache.put(reservation.getConsistentHashKey(), reservation);
    }

    public void cancelReservation(UniqueValueActor.Cancellation cancellation) {
        if (ttl == 0) {
            return;
        }
        cache.invalidate(cancellation.getConsistentHashKey());
    }

    public void cancelReservation(UniqueValueActor.Response response) {
        if (ttl == 0) {
            return;
        }
        cache.invalidate(response.getConsistentHashKey());
    }

    public CacheStats getStats() {
        return cache.stats();
    }

    public long getSize() {
        return cache.size();
    }
}