org.apache.hadoop.hive.ql.plan.mapper.CachingStatsSource.java Source code

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Here is the source code for org.apache.hadoop.hive.ql.plan.mapper.CachingStatsSource.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.hadoop.hive.ql.plan.mapper;

import java.util.Map;
import java.util.Map.Entry;
import java.util.Optional;

import org.apache.hadoop.hive.ql.exec.Operator;
import org.apache.hadoop.hive.ql.optimizer.signature.OpTreeSignature;
import org.apache.hadoop.hive.ql.stats.OperatorStats;

import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;

public class CachingStatsSource implements StatsSource {

    private final Cache<OpTreeSignature, OperatorStats> cache;

    public CachingStatsSource(int cacheSize) {
        cache = CacheBuilder.newBuilder().maximumSize(cacheSize).build();
    }

    public void put(OpTreeSignature sig, OperatorStats opStat) {
        cache.put(sig, opStat);
    }

    @Override
    public Optional<OperatorStats> lookup(OpTreeSignature treeSig) {
        return Optional.ofNullable(cache.getIfPresent(treeSig));
    }

    @Override
    public boolean canProvideStatsFor(Class<?> clazz) {
        if (cache.size() > 0 && Operator.class.isAssignableFrom(clazz)) {
            return true;
        }
        return false;
    }

    @Override
    public void putAll(Map<OpTreeSignature, OperatorStats> map) {
        for (Entry<OpTreeSignature, OperatorStats> entry : map.entrySet()) {
            put(entry.getKey(), entry.getValue());
        }
    }

}