PR for BAEL-2838 (eugenp#6970)

* Singleton injection examples and tests added * code and tests implemented * test refactored

Author: enpy303

jee-7/src/test/java/com/baeldung/singleton/CarServiceIntegrationTest.java

@@ -10,6 +10,10 @@
 import java.util.UUID;
 
 import javax.ejb.EJB;
+import javax.enterprise.context.spi.CreationalContext;
+import javax.enterprise.inject.spi.Bean;
+import javax.enterprise.inject.spi.BeanManager;
+import javax.enterprise.inject.spi.CDI;
 import javax.inject.Inject;
 
 import org.jboss.arquillian.container.test.api.Deployment;
@@ -47,68 +51,31 @@ public static JavaArchive createDeployment() {
 
  @EJB
  private CarServiceEjbSingleton carServiceEjbSingleton;
-
- private static Map<String, UUID> idMap = new HashMap<>();
-
- @Before
- public void setUp() {
- // populate idMap only on first run
- if (idMap.isEmpty()) {
- LOG.info("setUp::carServiceBean: {}", carServiceBean.getId());
- idMap.put("carServiceBeanId", carServiceBean.getId());
-
- LOG.info("setUp::carServiceSingleton: {}", carServiceSingleton.getId());
- idMap.put("carServiceSingletonId", carServiceSingleton.getId());
-
- LOG.info("setUp::carServiceEjbSingleton: {}", carServiceEjbSingleton.getId());
- idMap.put("carServiceEjbSingletonId", carServiceEjbSingleton.getId());
- }
- }
-
+ 
  @Test
- public void givenRun1_whenGetId_thenSingletonIdEqual() {
- int testRun = 1;
-
- assertNotNull(carServiceBean);
- assertNotNull(carServiceSingleton);
- assertNotNull(carServiceEjbSingleton);
-
- UUID carServiceBeanId = carServiceBean.getId();
- assertEquals(idMap.get("carServiceBeanId"), carServiceBeanId);
- LOG.info("Test run {}::carServiceBeanId: {}", testRun, carServiceBeanId);
-
- UUID carServiceSingletonId = carServiceSingleton.getId();
- assertEquals(idMap.get("carServiceSingletonId"), carServiceSingletonId);
- LOG.info("Test run {}::carServiceSingletonId: {}", testRun, carServiceSingletonId);
-
- UUID carServiceEjbSingletonId = carServiceEjbSingleton.getId();
- assertEquals(idMap.get("carServiceEjbSingletonId"), carServiceEjbSingletonId);
- LOG.info("Test run {}::carServiceEjbSingletonId: {}", testRun, carServiceEjbSingletonId);
+ public void givenASingleton_whenGetBeanIsCalledTwice_thenTheSameInstanceIsReturned() { 
+ CarServiceSingleton one = getBean(CarServiceSingleton.class);
+ CarServiceSingleton two = getBean(CarServiceSingleton.class);
+ assertTrue(one == two);
  }
-
+ 
  @Test
- public void givenRun2_whenGetId_thenSingletonIdEqual() {
- int testRun = 2;
-
- assertNotNull(carServiceBean);
- assertNotNull(carServiceSingleton);
- assertNotNull(carServiceEjbSingleton);
-
- UUID carServiceBeanId = carServiceBean.getId();
- assertNotEquals(idMap.get("carServiceBeanId"), carServiceBeanId);
- LOG.info("Test run {}::carServiceBeanId: {}", testRun, carServiceBeanId);
-
- UUID carServiceSingletonId = carServiceSingleton.getId();
- assertEquals(idMap.get("carServiceSingletonId"), carServiceSingletonId);
- LOG.info("Test run {}::carServiceSingletonId: {}", testRun, carServiceSingletonId);
+ public void givenAPojo_whenGetBeanIsCalledTwice_thenDifferentInstancesAreReturned() { 
+ CarServiceBean one = getBean(CarServiceBean.class);
+ CarServiceBean two = getBean(CarServiceBean.class);
+ assertTrue(one != two);
+ }
 
- UUID carServiceEjbSingletonId = carServiceEjbSingleton.getId();
- assertEquals(idMap.get("carServiceEjbSingletonId"), carServiceEjbSingletonId);
- LOG.info("Test run {}::carServiceEjbSingletonId: {}", testRun, carServiceEjbSingletonId);
+ @SuppressWarnings("unchecked")
+ private <T> T getBean(Class<T> beanClass) {
+ BeanManager bm = CDI.current().getBeanManager();
+ Bean<T> bean = (Bean<T>) bm.getBeans(beanClass).iterator().next();
+ CreationalContext<T> ctx = bm.createCreationalContext(bean);
+ return (T) bm.getReference(bean, beanClass, ctx);
  }
 
  @Test
- public void givenRun3_whenSingleton_thenNoLocking() {
+ public void givenCDI_whenConcurrentAccess_thenLockingIsNotProvided() {
  for (int i = 0; i < 10; i++) {
  new Thread(new Runnable() {
  @Override
@@ -124,7 +91,7 @@ public void run() {
  }
 
  @Test
- public void givenRun4_whenEjb_thenLocking() {
+ public void givenEJB_whenConcurrentAccess_thenLockingIsProvided() {
  for (int i = 0; i < 10; i++) {
  new Thread(new Runnable() {
  @Override