1 /* 2 * Copyright 2018, OpenCensus Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package io.opencensus.common; 18 19 import com.google.auto.value.AutoValue; 20 import javax.annotation.concurrent.Immutable; 21 22 /** 23 * A representation of stats measured on the server side. 24 * 25 * @since 0.16 26 */ 27 @Immutable 28 @AutoValue 29 public abstract class ServerStats { 30 ServerStats()31 ServerStats() {} 32 33 /** 34 * Returns Load Balancer latency, a latency observed at Load Balancer. 35 * 36 * @return Load Balancer latency in nanoseconds. 37 * @since 0.16 38 */ getLbLatencyNs()39 public abstract long getLbLatencyNs(); 40 41 /** 42 * Returns Service latency, a latency observed at Server. 43 * 44 * @return Service latency in nanoseconds. 45 * @since 0.16 46 */ getServiceLatencyNs()47 public abstract long getServiceLatencyNs(); 48 49 /** 50 * Returns Trace options, a set of bits indicating properties of trace. 51 * 52 * @return Trace options a set of bits indicating properties of trace. 53 * @since 0.16 54 */ getTraceOption()55 public abstract byte getTraceOption(); 56 57 /** 58 * Creates new {@link ServerStats} from specified parameters. 59 * 60 * @param lbLatencyNs Represents request processing latency observed on Load Balancer. It is 61 * measured in nanoseconds. Must not be less than 0. Value of 0 represents that the latency is 62 * not measured. 63 * @param serviceLatencyNs Represents request processing latency observed on Server. It is 64 * measured in nanoseconds. Must not be less than 0. Value of 0 represents that the latency is 65 * not measured. 66 * @param traceOption Represents set of bits to indicate properties of trace. Currently it used 67 * only the least signification bit to represent sampling of the request on the server side. 68 * Other bits are ignored. 69 * @return new {@code ServerStats} with specified fields. 70 * @throws IllegalArgumentException if the arguments are out of range. 71 * @since 0.16 72 */ create(long lbLatencyNs, long serviceLatencyNs, byte traceOption)73 public static ServerStats create(long lbLatencyNs, long serviceLatencyNs, byte traceOption) { 74 75 if (lbLatencyNs < 0) { 76 throw new IllegalArgumentException("'getLbLatencyNs' is less than zero: " + lbLatencyNs); 77 } 78 79 if (serviceLatencyNs < 0) { 80 throw new IllegalArgumentException( 81 "'getServiceLatencyNs' is less than zero: " + serviceLatencyNs); 82 } 83 84 return new AutoValue_ServerStats(lbLatencyNs, serviceLatencyNs, traceOption); 85 } 86 } 87