| /* |
| * 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.geronimo.microprofile.metrics.common; |
| |
| import java.time.Clock; |
| import java.time.Instant; |
| import java.time.ZoneId; |
| import java.util.concurrent.atomic.AtomicLong; |
| |
| import org.eclipse.microprofile.metrics.ConcurrentGauge; |
| |
| // this minute thing is stupid but what the TCK expect...todo: move to a scheduledexecutor to avoid that stupid cost |
| public class ConcurrentGaugeImpl implements ConcurrentGauge { |
| private static final Clock CLOCK = Clock.tickMinutes(ZoneId.of("UTC")); |
| |
| private final AtomicLong delegate = new AtomicLong(); |
| private final AtomicLong min = new AtomicLong(); |
| private final AtomicLong max = new AtomicLong(); |
| |
| private volatile Instant currentMinute = CLOCK.instant(); |
| |
| private volatile long lastMax = 0; |
| private volatile long lastMin = 0; |
| private final String unit; |
| |
| public ConcurrentGaugeImpl(final String unit) { |
| this.unit = unit; |
| } |
| |
| public String getUnit() { |
| return unit; |
| } |
| |
| @Override |
| public void inc() { |
| maybeRotate(); |
| synchronized (this) { |
| final long value = delegate.incrementAndGet(); |
| final long max = this.max.get(); |
| if (max < value) { |
| this.max.set(value); |
| } |
| } |
| } |
| |
| @Override |
| public void dec() { |
| maybeRotate(); |
| synchronized (this) { |
| final long value = delegate.decrementAndGet(); |
| final long min = this.min.get(); |
| if (min < value) { |
| this.min.set(value); |
| } |
| } |
| } |
| |
| @Override |
| public long getCount() { |
| maybeRotate(); |
| return delegate.get(); |
| } |
| |
| @Override |
| public long getMax() { |
| maybeRotate(); |
| return lastMax; |
| } |
| |
| @Override |
| public long getMin() { |
| maybeRotate(); |
| return lastMin; |
| } |
| |
| private void maybeRotate() { |
| final Instant now = CLOCK.instant(); |
| if (now.isAfter(currentMinute)) { |
| synchronized (this) { |
| if (now.isAfter(currentMinute)) { |
| final long count = delegate.get(); |
| lastMin = min.getAndSet(count); |
| lastMax = max.getAndSet(count); |
| min.set(count); |
| max.set(count); |
| currentMinute = now; |
| } |
| } |
| } |
| } |
| } |