Java tutorial
/* * Copyright 2013 Proofpoint, Inc. * * 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.airlift.stats; import com.fasterxml.jackson.annotation.JsonCreator; import com.fasterxml.jackson.annotation.JsonProperty; import com.google.common.base.Ticker; import io.airlift.stats.TimeDistribution.TimeDistributionSnapshot; import io.airlift.units.Duration; import org.weakref.jmx.Managed; import org.weakref.jmx.Nested; import java.util.concurrent.Callable; import java.util.concurrent.TimeUnit; import static com.google.common.base.MoreObjects.toStringHelper; public class TimeStat { private final TimeDistribution oneMinute; private final TimeDistribution fiveMinutes; private final TimeDistribution fifteenMinutes; private final TimeDistribution allTime; private final Ticker ticker; public TimeStat() { this(Ticker.systemTicker(), TimeUnit.SECONDS); } public TimeStat(Ticker ticker) { this(ticker, TimeUnit.SECONDS); } public TimeStat(TimeUnit unit) { this(Ticker.systemTicker(), unit); } public TimeStat(Ticker ticker, TimeUnit unit) { this.ticker = ticker; oneMinute = new TimeDistribution(ExponentialDecay.oneMinute(), unit); fiveMinutes = new TimeDistribution(ExponentialDecay.fiveMinutes(), unit); fifteenMinutes = new TimeDistribution(ExponentialDecay.fifteenMinutes(), unit); allTime = new TimeDistribution(unit); } public void add(double value, TimeUnit timeUnit) { add(new Duration(value, timeUnit)); } public void add(Duration duration) { add((long) duration.getValue(TimeUnit.NANOSECONDS)); } private void add(long value) { oneMinute.add(value); fiveMinutes.add(value); fifteenMinutes.add(value); allTime.add(value); } public <T> T time(Callable<T> callable) throws Exception { long start = ticker.read(); T result = callable.call(); add(ticker.read() - start); return result; } public BlockTimer time() { return new BlockTimer(); } public class BlockTimer implements AutoCloseable { private final long start = ticker.read(); @Override public void close() { add(ticker.read() - start); } } @Managed @Nested public TimeDistribution getOneMinute() { return oneMinute; } @Managed @Nested public TimeDistribution getFiveMinutes() { return fiveMinutes; } @Managed @Nested public TimeDistribution getFifteenMinutes() { return fifteenMinutes; } @Managed @Nested public TimeDistribution getAllTime() { return allTime; } public TimeDistributionStatSnapshot snapshot() { return new TimeDistributionStatSnapshot(getOneMinute().snapshot(), getFiveMinutes().snapshot(), getFifteenMinutes().snapshot(), getAllTime().snapshot()); } public static class TimeDistributionStatSnapshot { private final TimeDistributionSnapshot oneMinute; private final TimeDistributionSnapshot fiveMinute; private final TimeDistributionSnapshot fifteenMinute; private final TimeDistributionSnapshot allTime; @JsonCreator public TimeDistributionStatSnapshot(@JsonProperty("oneMinute") TimeDistributionSnapshot oneMinute, @JsonProperty("fiveMinute") TimeDistributionSnapshot fiveMinute, @JsonProperty("fifteenMinute") TimeDistributionSnapshot fifteenMinute, @JsonProperty("allTime") TimeDistributionSnapshot allTime) { this.oneMinute = oneMinute; this.fiveMinute = fiveMinute; this.fifteenMinute = fifteenMinute; this.allTime = allTime; } @JsonProperty public TimeDistributionSnapshot getOneMinute() { return oneMinute; } @JsonProperty public TimeDistributionSnapshot getFiveMinutes() { return fiveMinute; } @JsonProperty public TimeDistributionSnapshot getFifteenMinutes() { return fifteenMinute; } @JsonProperty public TimeDistributionSnapshot getAllTime() { return allTime; } @Override public String toString() { return toStringHelper(this).add("oneMinute", oneMinute).add("fiveMinute", fiveMinute) .add("fifteenMinute", fifteenMinute).add("allTime", allTime).toString(); } } }