1 /* 2 * Copyright 2017, 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.testing.export; 18 19 import io.opencensus.trace.export.SpanData; 20 import io.opencensus.trace.export.SpanExporter; 21 import java.util.ArrayList; 22 import java.util.Collection; 23 import java.util.List; 24 import javax.annotation.Nullable; 25 import javax.annotation.concurrent.GuardedBy; 26 27 /** 28 * A {@link SpanExporter.Handler} for testing only. 29 * 30 * @since 0.9 31 */ 32 public final class TestHandler extends SpanExporter.Handler { 33 34 private final Object monitor = new Object(); 35 36 @GuardedBy("monitor") 37 private final List<SpanData> spanDataList = new ArrayList<>(); 38 39 @Override export(Collection<SpanData> spanDataList)40 public void export(Collection<SpanData> spanDataList) { 41 synchronized (monitor) { 42 this.spanDataList.addAll(spanDataList); 43 monitor.notifyAll(); 44 } 45 } 46 47 /** 48 * Waits until we received numberOfSpans spans to export. Returns the list of exported {@link 49 * SpanData} objects, otherwise {@code null} if the current thread is interrupted. 50 * 51 * @param numberOfSpans the number of minimum spans to be collected. 52 * @return the list of exported {@link SpanData} objects, otherwise {@code null} if the current 53 * thread is interrupted. 54 * @since 0.9 55 */ 56 @Nullable waitForExport(int numberOfSpans)57 public List<SpanData> waitForExport(int numberOfSpans) { 58 List<SpanData> ret; 59 synchronized (monitor) { 60 while (spanDataList.size() < numberOfSpans) { 61 try { 62 monitor.wait(); 63 } catch (InterruptedException e) { 64 // Preserve the interruption status as per guidance. 65 Thread.currentThread().interrupt(); 66 return null; 67 } 68 } 69 ret = new ArrayList<>(spanDataList); 70 spanDataList.clear(); 71 } 72 return ret; 73 } 74 } 75