| /* |
| * Copyright 2016-17, OpenCensus Authors |
| * |
| * Licensed 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 io.opencensus.impl.internal; |
| |
| import static com.google.common.truth.Truth.assertThat; |
| |
| import io.opencensus.implcore.internal.EventQueue; |
| import org.junit.Test; |
| import org.junit.runner.RunWith; |
| import org.junit.runners.JUnit4; |
| |
| /** Unit tests for {@link DisruptorEventQueue}. */ |
| @RunWith(JUnit4.class) |
| public class DisruptorEventQueueTest { |
| // Simple class to use that keeps an incrementing counter. Will fail with an assertion if |
| // increment is used from multiple threads, or if the stored value is different from that expected |
| // by the caller. |
| private static class Counter { |
| private int count; |
| private volatile long id; // stores thread ID used in first increment operation. |
| |
| public Counter() { |
| count = 0; |
| id = -1; |
| } |
| |
| // Increments counter by 1. Will fail in assertion if multiple different threads are used |
| // (the EventQueue backend should be single-threaded). |
| public void increment() { |
| long tid = Thread.currentThread().getId(); |
| if (id == -1) { |
| assertThat(count).isEqualTo(0); |
| id = tid; |
| } else { |
| assertThat(id).isEqualTo(tid); |
| } |
| count++; |
| } |
| |
| // Check the current value of the counter. Assert if it is not the expected value. |
| public void check(int value) { |
| assertThat(count).isEqualTo(value); |
| } |
| } |
| |
| // EventQueueEntry for incrementing a Counter. |
| private static class IncrementEvent implements EventQueue.Entry { |
| private final Counter counter; |
| |
| IncrementEvent(Counter counter) { |
| this.counter = counter; |
| } |
| |
| @Override |
| public void process() { |
| counter.increment(); |
| } |
| } |
| |
| @Test |
| public void incrementOnce() { |
| Counter counter = new Counter(); |
| IncrementEvent ie = new IncrementEvent(counter); |
| DisruptorEventQueue.getInstance().enqueue(ie); |
| // Sleep briefly, to allow background operations to complete. |
| try { |
| Thread.sleep(500); |
| } catch (InterruptedException ex) { |
| Thread.currentThread().interrupt(); |
| } |
| counter.check(1); |
| } |
| |
| @Test |
| public void incrementTenK() { |
| final int tenK = 10000; |
| Counter counter = new Counter(); |
| for (int i = 0; i < tenK; i++) { |
| IncrementEvent ie = new IncrementEvent(counter); |
| DisruptorEventQueue.getInstance().enqueue(ie); |
| } |
| // Sleep briefly, to allow background operations to complete. |
| try { |
| Thread.sleep(500); |
| } catch (InterruptedException ex) { |
| Thread.currentThread().interrupt(); |
| } |
| counter.check(tenK); |
| } |
| } |