com.github.benmanes.caffeine.cache.simulator.policy.product.Cache2kPolicy.java Source code

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Here is the source code for com.github.benmanes.caffeine.cache.simulator.policy.product.Cache2kPolicy.java

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/*
 * Copyright 2015 Ben Manes. All Rights Reserved.
 *
 * 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 com.github.benmanes.caffeine.cache.simulator.policy.product;

import java.io.PrintStream;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.LogManager;
import java.util.logging.Logger;

import org.cache2k.Cache;
import org.cache2k.Cache2kBuilder;

import com.github.benmanes.caffeine.cache.simulator.BasicSettings;
import com.github.benmanes.caffeine.cache.simulator.policy.Policy;
import com.github.benmanes.caffeine.cache.simulator.policy.PolicyStats;
import com.google.common.collect.ImmutableSet;
import com.google.common.io.ByteStreams;
import com.typesafe.config.Config;

/**
 * Cache2k implementation.
 *
 * @author ben.manes@gmail.com (Ben Manes)
 */
public final class Cache2kPolicy implements Policy {
    private final Cache<Object, Object> cache;
    private final PolicyStats policyStats;
    private final int maximumSize;

    @SuppressWarnings("deprecation")
    public Cache2kPolicy(Config config) {
        Logger logger = LogManager.getLogManager().getLogger("");
        Level level = logger.getLevel();
        logger.setLevel(Level.OFF);
        PrintStream err = System.err;
        System.setErr(new PrintStream(ByteStreams.nullOutputStream()));
        try {
            this.policyStats = new PolicyStats("product.Cache2k");
            BasicSettings settings = new BasicSettings(config);
            cache = Cache2kBuilder.of(Object.class, Object.class).entryCapacity(settings.maximumSize())
                    .eternal(true).build();
            maximumSize = settings.maximumSize();
        } finally {
            System.setErr(err);
            LogManager.getLogManager().getLogger("").setLevel(level);
        }
    }

    /** Returns all variations of this policy based on the configuration parameters. */
    public static Set<Policy> policies(Config config) {
        return ImmutableSet.of(new Cache2kPolicy(config));
    }

    @Override
    @SuppressWarnings("deprecation")
    public void record(long key) {
        Object value = cache.peek(key);
        if (value == null) {
            policyStats.recordMiss();
            if (cache.getTotalEntryCount() == maximumSize) {
                policyStats.recordEviction();
            }
            cache.put(key, key);
        } else {
            policyStats.recordHit();
        }
    }

    @Override
    public PolicyStats stats() {
        return policyStats;
    }
}