Migrate to JUnit5

singleton/pom.xml

@@ -34,8 +34,13 @@
   <artifactId>singleton</artifactId>
   <dependencies>
     <dependency>
-      <groupId>junit</groupId>
-      <artifactId>junit</artifactId>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-api</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-engine</artifactId>
       <scope>test</scope>
     </dependency>
   </dependencies>

singleton/src/test/java/com/iluwatar/singleton/AppTest.java

@@ -22,7 +22,7 @@
  */
 package com.iluwatar.singleton;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 /**
  * 

singleton/src/test/java/com/iluwatar/singleton/SingletonTest.java

@@ -22,8 +22,8 @@
  */
 package com.iluwatar.singleton;
 
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertSame;
+import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.Test;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -32,7 +32,11 @@ import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.function.Supplier;
-import org.junit.Test;
+
+import static java.time.Duration.ofMillis;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertTimeout;
 
 /**
  * This class provides several test case that test singleton construction.
@@ -80,29 +84,30 @@ public abstract class SingletonTest<S> {
   /**
    * Test singleton instance in a concurrent setting
    */
-  @Test(timeout = 10000)
+  @Test
   public void testMultipleCallsReturnTheSameObjectInDifferentThreads() throws Exception {
+    assertTimeout(ofMillis(10000), () -> {
+      // Create 10000 tasks and inside each callable instantiate the singleton class
+      final List<Callable<S>> tasks = new ArrayList<>();
+      for (int i = 0; i < 10000; i++) {
+        tasks.add(this.singletonInstanceMethod::get);
+      }
 
-    // Create 10000 tasks and inside each callable instantiate the singleton class
-    final List<Callable<S>> tasks = new ArrayList<>();
-    for (int i = 0; i < 10000; i++) {
-      tasks.add(this.singletonInstanceMethod::get);
-    }
+      // Use up to 8 concurrent threads to handle the tasks
+      final ExecutorService executorService = Executors.newFixedThreadPool(8);
+      final List<Future<S>> results = executorService.invokeAll(tasks);
 
-    // Use up to 8 concurrent threads to handle the tasks
-    final ExecutorService executorService = Executors.newFixedThreadPool(8);
-    final List<Future<S>> results = executorService.invokeAll(tasks);
+      // wait for all of the threads to complete
+      final S expectedInstance = this.singletonInstanceMethod.get();
+      for (Future<S> res : results) {
+        final S instance = res.get();
+        assertNotNull(instance);
+        assertSame(expectedInstance, instance);
+      }
 
-    // wait for all of the threads to complete
-    final S expectedInstance = this.singletonInstanceMethod.get();
-    for (Future<S> res : results) {
-      final S instance = res.get();
-      assertNotNull(instance);
-      assertSame(expectedInstance, instance);
-    }
-
-    // tidy up the executor
-    executorService.shutdown();
+      // tidy up the executor
+      executorService.shutdown();
+    });
 
   }