diff --git a/core-java-modules/core-java-concurrency-collections-2/pom.xml b/core-java-modules/core-java-concurrency-collections-2/pom.xml index 65a91c9a9c..7fdd348dc5 100644 --- a/core-java-modules/core-java-concurrency-collections-2/pom.xml +++ b/core-java-modules/core-java-concurrency-collections-2/pom.xml @@ -23,7 +23,12 @@ jmh-generator-annprocess ${jmh.version} - + + org.assertj + assertj-core + ${assertj.version} + test + src @@ -42,6 +47,8 @@ 1.21 28.2-jre + + 3.6.1 \ No newline at end of file diff --git a/core-java-modules/core-java-concurrency-collections-2/src/test/java/com/baeldung/concurrent/queue/TestConcurrentLinkedQueue.java b/core-java-modules/core-java-concurrency-collections-2/src/test/java/com/baeldung/concurrent/queue/TestConcurrentLinkedQueue.java new file mode 100644 index 0000000000..c61becc366 --- /dev/null +++ b/core-java-modules/core-java-concurrency-collections-2/src/test/java/com/baeldung/concurrent/queue/TestConcurrentLinkedQueue.java @@ -0,0 +1,66 @@ +package com.baeldung.concurrent.queue; + +import static org.assertj.core.api.Assertions.assertThat; +import static org.hamcrest.CoreMatchers.equalTo; +import static org.hamcrest.CoreMatchers.is; +import static org.junit.Assert.assertNull; +import static org.junit.Assert.assertThat; + +import java.util.Arrays; +import java.util.Collection; +import java.util.concurrent.Callable; +import java.util.concurrent.ConcurrentLinkedQueue; +import java.util.concurrent.ExecutorService; +import java.util.concurrent.Executors; +import java.util.concurrent.Future; +import java.util.concurrent.TimeUnit; + +import org.junit.FixMethodOrder; +import org.junit.Test; + +@FixMethodOrder +public class TestConcurrentLinkedQueue { + + @Test + public void givenThereIsExistingCollection_WhenAddedIntoQueue_ThenShouldContainElements() { + Collection elements = Arrays.asList(1, 2, 3, 4, 5); + ConcurrentLinkedQueue concurrentLinkedQueue = new ConcurrentLinkedQueue<>(elements); + assertThat(concurrentLinkedQueue).containsExactly(1, 2, 3, 4, 5); + } + + @Test + public void givenQueueIsEmpty_WhenAccessingTheQueue_ThenQueueReturnsNull() throws InterruptedException { + ExecutorService executorService = Executors.newFixedThreadPool(1); + ConcurrentLinkedQueue concurrentLinkedQueue = new ConcurrentLinkedQueue<>(); + executorService.submit(() -> assertNull("Retrieve object is null", concurrentLinkedQueue.poll())); + TimeUnit.SECONDS.sleep(1); + executorService.awaitTermination(1, TimeUnit.SECONDS); + executorService.shutdown(); + } + + @Test + public void givenProducerOffersElementInQueue_WhenConsumerPollsQueue_ThenItRetrievesElement() throws Exception { + int element = 1; + + ExecutorService executorService = Executors.newFixedThreadPool(2); + ConcurrentLinkedQueue concurrentLinkedQueue = new ConcurrentLinkedQueue<>(); + Runnable offerTask = () -> concurrentLinkedQueue.offer(element); + + Callable pollTask = () -> { + while (concurrentLinkedQueue.peek() != null) { + return concurrentLinkedQueue.poll() + .intValue(); + } + return null; + }; + + executorService.submit(offerTask); + TimeUnit.SECONDS.sleep(1); + + Future returnedElement = executorService.submit(pollTask); + assertThat(returnedElement.get() + .intValue(), is(equalTo(element))); + executorService.awaitTermination(1, TimeUnit.SECONDS); + executorService.shutdown(); + } +} diff --git a/core-java-modules/core-java-concurrency-collections-2/src/test/java/com/baeldung/concurrent/queue/TestLinkedBlockingQueue.java b/core-java-modules/core-java-concurrency-collections-2/src/test/java/com/baeldung/concurrent/queue/TestLinkedBlockingQueue.java new file mode 100644 index 0000000000..7a78bc7b3b --- /dev/null +++ b/core-java-modules/core-java-concurrency-collections-2/src/test/java/com/baeldung/concurrent/queue/TestLinkedBlockingQueue.java @@ -0,0 +1,81 @@ +package com.baeldung.concurrent.queue; + +import static org.assertj.core.api.Assertions.assertThat; +import static org.hamcrest.CoreMatchers.equalTo; +import static org.hamcrest.CoreMatchers.is; +import static org.junit.Assert.assertThat; + +import java.util.Arrays; +import java.util.Collection; +import java.util.concurrent.Callable; +import java.util.concurrent.ExecutorService; +import java.util.concurrent.Executors; +import java.util.concurrent.Future; +import java.util.concurrent.LinkedBlockingQueue; +import java.util.concurrent.TimeUnit; + +import org.junit.FixMethodOrder; +import org.junit.Test; + +@FixMethodOrder +public class TestLinkedBlockingQueue { + + @Test + public void givenThereIsExistingCollection_WhenAddedIntoQueue_ThenShouldContainElements() { + Collection elements = Arrays.asList(1, 2, 3, 4, 5); + LinkedBlockingQueue linkedBlockingQueue = new LinkedBlockingQueue<>(elements); + assertThat(linkedBlockingQueue).containsExactly(1, 2, 3, 4, 5); + } + + @Test + public void givenQueueIsEmpty_WhenAccessingTheQueue_ThenThreadBlocks() throws InterruptedException { + ExecutorService executorService = Executors.newFixedThreadPool(1); + LinkedBlockingQueue linkedBlockingQueue = new LinkedBlockingQueue<>(); + executorService.submit(() -> { + try { + linkedBlockingQueue.take(); + } catch (InterruptedException e) { + e.printStackTrace(); + } + }); + TimeUnit.SECONDS.sleep(1); + executorService.awaitTermination(1, TimeUnit.SECONDS); + executorService.shutdown(); + } + + @Test + public void givenProducerPutsElementInQueue_WhenConsumerAccessQueue_ThenItRetrieve() { + int element = 10; + ExecutorService executorService = Executors.newFixedThreadPool(2); + LinkedBlockingQueue linkedBlockingQueue = new LinkedBlockingQueue<>(); + Runnable putTask = () -> { + try { + linkedBlockingQueue.put(element); + } catch (InterruptedException e) { + e.printStackTrace(); + } + }; + + Callable takeTask = () -> { + try { + return linkedBlockingQueue.take(); + } catch (InterruptedException e) { + e.printStackTrace(); + } + return null; + }; + + executorService.submit(putTask); + Future returnElement = executorService.submit(takeTask); + try { + TimeUnit.SECONDS.sleep(1); + assertThat(returnElement.get() + .intValue(), is(equalTo(element))); + executorService.awaitTermination(1, TimeUnit.SECONDS); + } catch (Exception e) { + e.printStackTrace(); + } + + executorService.shutdown(); + } +}