org.apache.aurora.scheduler.testing.FakeStatsProvider.java Source code

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Here is the source code for org.apache.aurora.scheduler.testing.FakeStatsProvider.java

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/**
 * 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 org.apache.aurora.scheduler.testing;

import java.util.Map;
import java.util.concurrent.atomic.AtomicLong;

import com.google.common.base.Supplier;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Maps;

import org.apache.aurora.common.stats.Stat;
import org.apache.aurora.common.stats.StatsProvider;

/**
 * A fake stats provider for use in testing.
 */
public class FakeStatsProvider implements StatsProvider {
    private final Map<String, Supplier<? extends Number>> stats = Maps.newHashMap();

    /**
     * Gets the current value of a stat.
     *
     * @param statName Name of the stat to fetch.
     * @return Current stat value.
     */
    public Number getValue(String statName) {
        return stats.get(statName).get();
    }

    /**
     * Gets the current values of all exported stats.
     *
     * @return All exported stat names and their associated values.
     */
    public Map<String, ? extends Number> getAllValues() {
        return ImmutableMap.copyOf(Maps.transformValues(stats, Supplier::get));
    }

    /**
     * Gets the value of a stat as a long.
     *
     * @param name Stat name.
     * @return Value, as a long.
     */
    public long getLongValue(String name) {
        return stats.get(name).get().longValue();
    }

    @Override
    public AtomicLong makeCounter(String name) {
        final AtomicLong counter = new AtomicLong();
        stats.put(name, counter::get);
        return counter;
    }

    @Override
    public <T extends Number> Stat<T> makeGauge(final String name, final Supplier<T> gauge) {
        stats.put(name, gauge);

        return new Stat<T>() {
            @Override
            public String getName() {
                return name;
            }

            @Override
            public T read() {
                return gauge.get();
            }
        };
    }

    @Override
    public StatsProvider untracked() {
        return this;
    }

    @Override
    public RequestTimer makeRequestTimer(String name) {
        throw new UnsupportedOperationException();
    }
}