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.metrics.export; 18 19 import com.google.auto.value.AutoValue; 20 import io.opencensus.common.ExperimentalApi; 21 import io.opencensus.common.Timestamp; 22 import io.opencensus.internal.Utils; 23 import io.opencensus.metrics.LabelKey; 24 import io.opencensus.metrics.LabelValue; 25 import java.util.ArrayList; 26 import java.util.Collections; 27 import java.util.List; 28 import javax.annotation.Nullable; 29 import javax.annotation.concurrent.Immutable; 30 31 /** 32 * A collection of data points that describes the time-varying values of a {@code Metric}. 33 * 34 * @since 0.17 35 */ 36 @ExperimentalApi 37 @Immutable 38 @AutoValue 39 public abstract class TimeSeries { 40 TimeSeries()41 TimeSeries() {} 42 43 /** 44 * Creates a {@link TimeSeries}. 45 * 46 * @param labelValues the {@code LabelValue}s that uniquely identify this {@code TimeSeries}. 47 * @param points the data {@code Point}s of this {@code TimeSeries}. 48 * @param startTimestamp the start {@code Timestamp} of this {@code TimeSeries}. Must be non-null 49 * for cumulative {@code Point}s. 50 * @return a {@code TimeSeries}. 51 * @since 0.17 52 */ create( List<LabelValue> labelValues, List<Point> points, @Nullable Timestamp startTimestamp)53 public static TimeSeries create( 54 List<LabelValue> labelValues, List<Point> points, @Nullable Timestamp startTimestamp) { 55 Utils.checkListElementNotNull(Utils.checkNotNull(points, "points"), "point"); 56 return createInternal( 57 labelValues, Collections.unmodifiableList(new ArrayList<Point>(points)), startTimestamp); 58 } 59 60 /** 61 * Creates a {@link TimeSeries} with empty(or no) points. 62 * 63 * @param labelValues the {@code LabelValue}s that uniquely identify this {@code TimeSeries}. 64 * @return a {@code TimeSeries}. 65 * @since 0.17 66 */ create(List<LabelValue> labelValues)67 public static TimeSeries create(List<LabelValue> labelValues) { 68 return createInternal(labelValues, Collections.<Point>emptyList(), null); 69 } 70 71 /** 72 * Creates a {@link TimeSeries}. 73 * 74 * @param labelValues the {@code LabelValue}s that uniquely identify this {@code TimeSeries}. 75 * @param point the single data {@code Point} of this {@code TimeSeries}. 76 * @param startTimestamp the start {@code Timestamp} of this {@code TimeSeries}. Must be non-null 77 * for cumulative {@code Point}s. 78 * @return a {@code TimeSeries}. 79 * @since 0.17 80 */ createWithOnePoint( List<LabelValue> labelValues, Point point, @Nullable Timestamp startTimestamp)81 public static TimeSeries createWithOnePoint( 82 List<LabelValue> labelValues, Point point, @Nullable Timestamp startTimestamp) { 83 Utils.checkNotNull(point, "point"); 84 return createInternal(labelValues, Collections.singletonList(point), startTimestamp); 85 } 86 87 /** 88 * Sets the {@code Point} of the {@link TimeSeries}. 89 * 90 * @param point the single data {@code Point} of this {@code TimeSeries}. 91 * @return a {@code TimeSeries}. 92 * @since 0.17 93 */ setPoint(Point point)94 public TimeSeries setPoint(Point point) { 95 Utils.checkNotNull(point, "point"); 96 return new AutoValue_TimeSeries(getLabelValues(), Collections.singletonList(point), null); 97 } 98 99 /** 100 * Creates a {@link TimeSeries}. 101 * 102 * @param labelValues the {@code LabelValue}s that uniquely identify this {@code TimeSeries}. 103 * @param points the data {@code Point}s of this {@code TimeSeries}. 104 * @param startTimestamp the start {@code Timestamp} of this {@code TimeSeries}. Must be non-null 105 * for cumulative {@code Point}s. 106 * @return a {@code TimeSeries}. 107 */ createInternal( List<LabelValue> labelValues, List<Point> points, @Nullable Timestamp startTimestamp)108 private static TimeSeries createInternal( 109 List<LabelValue> labelValues, List<Point> points, @Nullable Timestamp startTimestamp) { 110 // Fail fast on null lists to prevent NullPointerException when copying the lists. 111 Utils.checkListElementNotNull(Utils.checkNotNull(labelValues, "labelValues"), "labelValue"); 112 return new AutoValue_TimeSeries( 113 Collections.unmodifiableList(new ArrayList<LabelValue>(labelValues)), 114 points, 115 startTimestamp); 116 } 117 118 /** 119 * Returns the set of {@link LabelValue}s that uniquely identify this {@link TimeSeries}. 120 * 121 * <p>Apply to all {@link Point}s. 122 * 123 * <p>The order of {@link LabelValue}s must match that of {@link LabelKey}s in the {@code 124 * MetricDescriptor}. 125 * 126 * @return the {@code LabelValue}s. 127 * @since 0.17 128 */ getLabelValues()129 public abstract List<LabelValue> getLabelValues(); 130 131 /** 132 * Returns the data {@link Point}s of this {@link TimeSeries}. 133 * 134 * @return the data {@code Point}s. 135 * @since 0.17 136 */ getPoints()137 public abstract List<Point> getPoints(); 138 139 /** 140 * Returns the start {@link Timestamp} of this {@link TimeSeries} if the {@link Point}s are 141 * cumulative, or {@code null} if the {@link Point}s are gauge. 142 * 143 * @return the start {@code Timestamp} or {@code null}. 144 * @since 0.17 145 */ 146 @Nullable getStartTimestamp()147 public abstract Timestamp getStartTimestamp(); 148 } 149