Java tutorial
/* * Copyright 2010-2019 Amazon.com, Inc. or its affiliates. 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. * A copy of the License is located at * * http://aws.amazon.com/apache2.0 * * or in the "license" file accompanying this file. This file 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.amazonaws.metrics; import org.apache.commons.logging.LogFactory; import com.amazonaws.annotation.NotThreadSafe; import com.amazonaws.util.TimingInfo; /** * ApiCallLatency metric information provider. */ @NotThreadSafe public class ServiceLatencyProvider { private final long startNano = System.nanoTime(); private long endNano = startNano; private final ServiceMetricType serviceMetricType; public ServiceLatencyProvider(ServiceMetricType type) { this.serviceMetricType = type; } public ServiceMetricType getServiceMetricType() { return serviceMetricType; } /** * Ends the timing. Must not be called more than once. */ public ServiceLatencyProvider endTiming() { if (endNano != startNano) { throw new IllegalStateException(); } endNano = System.nanoTime(); return this; } public double getDurationMilli() { if (endNano == startNano) { LogFactory.getLog(getClass()).debug("Likely to be a missing invocation of endTiming()."); } return TimingInfo.durationMilliOf(startNano, endNano); } public String getProviderId() { return super.toString(); } @Override public String toString() { return String.format("providerId=%s, serviceMetricType=%s, startNano=%d, endNano=%d", getProviderId(), serviceMetricType, startNano, endNano); } }