Java 11 migrate remaining e (#1112)

* Moves eip-aggregator to Java 11

* Moves eip-message-channel to Java 11

* Moves eip-publish-subscribe to Java 11

* Moves eip-splitter to Java 11

* Moves eip-wire-tap to Java 11

* Moves event-aggregator to Java 11

* Moves event-asynchronous to Java 11

* Moves event-driven-architecture to Java 11

* Moves event-queue to Java 11

* Moves event-sourcing to Java 11

* Moves execute-around to Java 11

* Moves extension-objects to Java 11

eip-aggregator/src/main/java/com/iluwatar/eip/aggregator/App.java

@@ -27,7 +27,6 @@ import org.apache.camel.CamelContext;
 import org.apache.camel.builder.RouteBuilder;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
-import org.springframework.context.ConfigurableApplicationContext;
 
 /**
  * Sometimes in enterprise systems there is a need to group incoming data in order to process it as
@@ -49,19 +48,17 @@ public class App {
    */
   public static void main(String[] args) throws Exception {
     // Run Spring Boot application and obtain ApplicationContext
-    ConfigurableApplicationContext context = SpringApplication.run(App.class, args);
+    var context = SpringApplication.run(App.class, args);
 
     // Get CamelContext from ApplicationContext
-    CamelContext camelContext = (CamelContext) context.getBean("camelContext");
+    var camelContext = (CamelContext) context.getBean("camelContext");
 
     // Add a new routes that will handle endpoints form SplitterRoute class.
     camelContext.addRoutes(new RouteBuilder() {
-
       @Override
-      public void configure() throws Exception {
+      public void configure() {
         from("{{endpoint}}").log("ENDPOINT: ${body}");
       }
-
     });
 
     // Add producer that will send test message to an entry point in WireTapRoute

eip-aggregator/src/main/java/com/iluwatar/eip/aggregator/routes/AggregatorRoute.java

@@ -48,8 +48,6 @@ public class AggregatorRoute extends RouteBuilder {
 
   /**
    * Configures the route.
-   *
-   * @throws Exception in case of exception during configuration
    */
   @Override
   public void configure() {

eip-aggregator/src/main/java/com/iluwatar/eip/aggregator/routes/MessageAggregationStrategy.java

@@ -40,8 +40,8 @@ public class MessageAggregationStrategy implements AggregationStrategy {
       return newExchange;
     }
 
-    String in1 = (String) oldExchange.getIn().getBody();
+    var in1 = (String) oldExchange.getIn().getBody();
-    String in2 = (String) newExchange.getIn().getBody();
+    var in2 = (String) newExchange.getIn().getBody();
 
     oldExchange.getIn().setBody(in1 + ";" + in2);
 

eip-aggregator/src/test/java/com/iluwatar/eip/aggregator/AppTest.java

@@ -32,7 +32,6 @@ public class AppTest {
 
   @Test
   public void testMain() throws Exception {
-    String[] args = {};
+    App.main(new String[]{});
-    App.main(args);
   }
 }

eip-aggregator/src/test/java/com/iluwatar/eip/aggregator/routes/AggregatorRouteTest.java

@@ -23,6 +23,8 @@
 
 package com.iluwatar.eip.aggregator.routes;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import org.apache.camel.EndpointInject;
 import org.apache.camel.ProducerTemplate;
 import org.apache.camel.component.mock.MockEndpoint;
@@ -35,13 +37,11 @@ import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.context.ActiveProfiles;
 import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-
 /**
  * Test class for <i>AggregatorRoute</i>.
  * <p>
- * In order for it to work we have to mock endpoints we want to read/write to. To mock those we need to substitute
+ * In order for it to work we have to mock endpoints we want to read/write to. To mock those we need
- * original endpoint names to mocks.
+ * to substitute original endpoint names to mocks.
  * </p>
  */
 @ExtendWith(SpringExtension.class)
@@ -59,6 +59,7 @@ public class AggregatorRouteTest {
 
   /**
    * Test if endpoint receives three separate messages.
+   *
    * @throws Exception in case of en exception during the test
    */
   @Test
@@ -76,10 +77,10 @@ public class AggregatorRouteTest {
     endpoint.expectedMessageCount(2);
     endpoint.assertIsSatisfied();
 
-    String body = (String) endpoint.getReceivedExchanges().get(0).getIn().getBody();
+    var body = (String) endpoint.getReceivedExchanges().get(0).getIn().getBody();
     assertEquals(3, body.split(";").length);
 
-    String body2 = (String) endpoint.getReceivedExchanges().get(1).getIn().getBody();
+    var body2 = (String) endpoint.getReceivedExchanges().get(1).getIn().getBody();
     assertEquals(2, body2.split(";").length);
   }
 }

eip-aggregator/src/test/java/com/iluwatar/eip/aggregator/routes/MessageAggregationStrategyTest.java

@@ -23,13 +23,12 @@
 
 package com.iluwatar.eip.aggregator.routes;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import org.apache.camel.CamelContext;
-import org.apache.camel.Exchange;
 import org.apache.camel.impl.DefaultExchange;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-
 /**
  * Tests MessageAggregationStrategy
  */
@@ -37,27 +36,27 @@ public class MessageAggregationStrategyTest {
 
   @Test
   public void testAggregate() {
-    MessageAggregationStrategy mas = new MessageAggregationStrategy();
+    var mas = new MessageAggregationStrategy();
-    Exchange oldExchange = new DefaultExchange((CamelContext) null);
+    var oldExchange = new DefaultExchange((CamelContext) null);
     oldExchange.getIn().setBody("TEST1");
 
-    Exchange newExchange = new DefaultExchange((CamelContext) null);
+    var newExchange = new DefaultExchange((CamelContext) null);
     newExchange.getIn().setBody("TEST2");
 
-    Exchange output = mas.aggregate(oldExchange, newExchange);
+    var output = mas.aggregate(oldExchange, newExchange);
-    String outputBody = (String) output.getIn().getBody();
+    var outputBody = (String) output.getIn().getBody();
     assertEquals("TEST1;TEST2", outputBody);
   }
 
   @Test
   public void testAggregateOldNull() {
-    MessageAggregationStrategy mas = new MessageAggregationStrategy();
+    var mas = new MessageAggregationStrategy();
 
-    Exchange newExchange = new DefaultExchange((CamelContext) null);
+    var newExchange = new DefaultExchange((CamelContext) null);
     newExchange.getIn().setBody("TEST2");
 
-    Exchange output = mas.aggregate(null, newExchange);
+    var output = mas.aggregate(null, newExchange);
-    String outputBody = (String) output.getIn().getBody();
+    var outputBody = (String) output.getIn().getBody();
 
     assertEquals(newExchange, output);
     assertEquals("TEST2", outputBody);

eip-message-channel/src/main/java/com/iluwatar/eip/message/channel/App.java

@@ -23,7 +23,6 @@
 
 package com.iluwatar.eip.message.channel;
 
-import org.apache.camel.CamelContext;
 import org.apache.camel.builder.RouteBuilder;
 import org.apache.camel.impl.DefaultCamelContext;
 import org.slf4j.Logger;
@@ -57,7 +56,7 @@ public class App {
    * Program entry point.
    */
   public static void main(String[] args) throws Exception {
-    CamelContext context = new DefaultCamelContext();
+    var context = new DefaultCamelContext();
 
     context.addRoutes(new RouteBuilder() {
 

eip-message-channel/src/test/java/com/iluwatar/eip/message/channel/AppTest.java

@@ -26,15 +26,12 @@ package com.iluwatar.eip.message.channel;
 import org.junit.jupiter.api.Test;
 
 /**
- * 
  * Application test
- *
  */
 public class AppTest {
 
   @Test
   public void test() throws Exception {
-    String[] args = {};
+    App.main(new String[]{});
-    App.main(args);
   }
 }

eip-publish-subscribe/src/main/java/com/iluwatar/eip/publish/subscribe/App.java

@@ -23,8 +23,6 @@
 
 package com.iluwatar.eip.publish.subscribe;
 
-import org.apache.camel.CamelContext;
-import org.apache.camel.ProducerTemplate;
 import org.apache.camel.builder.RouteBuilder;
 import org.apache.camel.impl.DefaultCamelContext;
 import org.slf4j.Logger;
@@ -55,14 +53,14 @@ public class App {
    * Program entry point.
    */
   public static void main(String[] args) throws Exception {
-    CamelContext context = new DefaultCamelContext();
+    var context = new DefaultCamelContext();
     context.addRoutes(new RouteBuilder() {
       @Override
       public void configure() throws Exception {
         from("direct:origin").multicast().to("mock:foo", "mock:bar", "stream:out");
       }
     });
-    ProducerTemplate template = context.createProducerTemplate();
+    var template = context.createProducerTemplate();
     context.start();
     context.getRoutes().forEach(r -> LOGGER.info(r.toString()));
     template.sendBody("direct:origin", "Hello from origin");

eip-publish-subscribe/src/test/java/com/iluwatar/eip/publish/subscribe/AppTest.java

@@ -26,15 +26,12 @@ package com.iluwatar.eip.publish.subscribe;
 import org.junit.jupiter.api.Test;
 
 /**
- * 
  * Application test
- *
  */
 public class AppTest {
 
   @Test
   public void test() throws Exception {
-    String[] args = {};
+    App.main(new String[]{});
-    App.main(args);
   }
 }

eip-splitter/src/main/java/com/iluwatar/eip/splitter/App.java

@@ -27,7 +27,6 @@ import org.apache.camel.CamelContext;
 import org.apache.camel.builder.RouteBuilder;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
-import org.springframework.context.ConfigurableApplicationContext;
 
 /**
  * It is very common in integration systems that incoming messages consists of many items bundled
@@ -53,10 +52,10 @@ public class App {
    */
   public static void main(String[] args) throws Exception {
     // Run Spring Boot application and obtain ApplicationContext
-    ConfigurableApplicationContext context = SpringApplication.run(App.class, args);
+    var context = SpringApplication.run(App.class, args);
 
     // Get CamelContext from ApplicationContext
-    CamelContext camelContext = (CamelContext) context.getBean("camelContext");
+    var camelContext = (CamelContext) context.getBean("camelContext");
 
     // Add a new routes that will handle endpoints form SplitterRoute class.
     camelContext.addRoutes(new RouteBuilder() {

eip-splitter/src/test/java/com/iluwatar/eip/splitter/AppTest.java

@@ -32,7 +32,6 @@ public class AppTest {
 
   @Test
   public void testMain() throws Exception {
-    String[] args = {};
+    App.main(new String[]{});
-    App.main(args);
   }
 }

eip-splitter/src/test/java/com/iluwatar/eip/splitter/routes/SplitterRouteTest.java

@@ -38,8 +38,8 @@ import org.springframework.test.context.junit.jupiter.SpringExtension;
 /**
  * Test class for <i>SplitterRoute</i>.
  * <p>
- * In order for it to work we have to mock endpoints we want to read/write to. To mock those we need to substitute
+ * In order for it to work we have to mock endpoints we want to read/write to. To mock those we need
- * original endpoint names to mocks.
+ * to substitute original endpoint names to mocks.
  * </p>
  */
 @ExtendWith(SpringExtension.class)
@@ -57,6 +57,7 @@ public class SplitterRouteTest {
 
   /**
    * Test if endpoint receives three separate messages.
+   *
    * @throws Exception in case of en exception during the test
    */
   @Test
@@ -64,7 +65,7 @@ public class SplitterRouteTest {
   public void testSplitter() throws Exception {
 
     // Three items in one entry message
-    entry.sendBody(new String[] {"TEST1", "TEST2", "TEST3"});
+    entry.sendBody(new String[]{"TEST1", "TEST2", "TEST3"});
 
     // Endpoint should have three different messages in the end order of the messages is not important
     endpoint.expectedMessageCount(3);

eip-wire-tap/src/main/java/com/iluwatar/eip/wiretap/App.java

@@ -27,7 +27,6 @@ import org.apache.camel.CamelContext;
 import org.apache.camel.builder.RouteBuilder;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
-import org.springframework.context.ConfigurableApplicationContext;
 
 /**
  * In most integration cases there is a need to monitor the messages flowing through the system. It
@@ -52,10 +51,10 @@ public class App {
    */
   public static void main(String[] args) throws Exception {
     // Run Spring Boot application and obtain ApplicationContext
-    ConfigurableApplicationContext context = SpringApplication.run(App.class, args);
+    var context = SpringApplication.run(App.class, args);
 
     // Get CamelContext from ApplicationContext
-    CamelContext camelContext = (CamelContext) context.getBean("camelContext");
+    var camelContext = (CamelContext) context.getBean("camelContext");
 
     // Add a new routes that will handle endpoints form WireTapRoute class.
     camelContext.addRoutes(new RouteBuilder() {

eip-wire-tap/src/test/java/com/iluwatar/eip/wiretap/AppTest.java

@@ -32,7 +32,6 @@ public class AppTest {
 
   @Test
   public void testMain() throws Exception {
-    String[] args = {};
+    App.main(new String[]{});
-    App.main(args);
   }
 }

eip-wire-tap/src/test/java/com/iluwatar/eip/wiretap/routes/WireTapRouteTest.java

@@ -23,8 +23,9 @@
 
 package com.iluwatar.eip.wiretap.routes;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import org.apache.camel.EndpointInject;
-import org.apache.camel.Message;
 import org.apache.camel.ProducerTemplate;
 import org.apache.camel.component.mock.MockEndpoint;
 import org.junit.jupiter.api.Test;
@@ -36,13 +37,11 @@ import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.context.ActiveProfiles;
 import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-
 /**
  * Test class for <i>WireTapRoute</i>.
  * <p>
- * In order for it to work we have to mock endpoints we want to read/write to. To mock those we need to substitute
+ * In order for it to work we have to mock endpoints we want to read/write to. To mock those we need
- * original endpoint names to mocks.
+ * to substitute original endpoint names to mocks.
  * </p>
  */
 @ExtendWith(SpringExtension.class)
@@ -63,6 +62,7 @@ public class WireTapRouteTest {
 
   /**
    * Test if both endpoints receive exactly one message containing the same, unchanged body.
+   *
    * @throws Exception in case of en exception during the test
    */
   @Test
@@ -76,8 +76,8 @@ public class WireTapRouteTest {
     endpoint.assertIsSatisfied();
     wireTapEndpoint.assertIsSatisfied();
 
-    Message endpointIn = endpoint.getExchanges().get(0).getIn();
+    var endpointIn = endpoint.getExchanges().get(0).getIn();
-    Message wireTapEndpointIn = wireTapEndpoint.getExchanges().get(0).getIn();
+    var wireTapEndpointIn = wireTapEndpoint.getExchanges().get(0).getIn();
 
     assertEquals("TEST", endpointIn.getBody());
     assertEquals("TEST", wireTapEndpointIn.getBody());

event-aggregator/src/main/java/com/iluwatar/event/aggregator/App.java

@@ -23,8 +23,9 @@
 
 package com.iluwatar.event.aggregator;
 
-import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
+import java.util.function.Consumer;
 
 /**
  * A system with lots of objects can lead to complexities when a client wants to subscribe to
@@ -47,19 +48,18 @@ public class App {
    */
   public static void main(String[] args) {
 
-    KingJoffrey kingJoffrey = new KingJoffrey();
+    var kingJoffrey = new KingJoffrey();
-    KingsHand kingsHand = new KingsHand(kingJoffrey);
+    var kingsHand = new KingsHand(kingJoffrey);
 
-    List<EventEmitter> emitters = new ArrayList<>();
+    var emitters = List.of(
-    emitters.add(kingsHand);
+        kingsHand,
-    emitters.add(new LordBaelish(kingsHand));
+        new LordBaelish(kingsHand),
-    emitters.add(new LordVarys(kingsHand));
+        new LordVarys(kingsHand),
-    emitters.add(new Scout(kingsHand));
+        new Scout(kingsHand)
+    );
 
-    for (Weekday day : Weekday.values()) {
+    Arrays.stream(Weekday.values())
-      for (EventEmitter emitter : emitters) {
+        .<Consumer<? super EventEmitter>>map(day -> emitter -> emitter.timePasses(day))
-        emitter.timePasses(day);
+        .forEachOrdered(emitters::forEach);
-      }
-    }
   }
 }

event-aggregator/src/main/java/com/iluwatar/event/aggregator/EventEmitter.java

@@ -47,9 +47,7 @@ public abstract class EventEmitter {
   }
 
   protected void notifyObservers(Event e) {
-    for (EventObserver obs : observers) {
+    observers.forEach(obs -> obs.onEvent(e));
-      obs.onEvent(e);
-    }
   }
 
   public abstract void timePasses(Weekday day);

event-aggregator/src/main/java/com/iluwatar/event/aggregator/LordBaelish.java

@@ -37,7 +37,7 @@ public class LordBaelish extends EventEmitter {
 
   @Override
   public void timePasses(Weekday day) {
-    if (day.equals(Weekday.FRIDAY)) {
+    if (day == Weekday.FRIDAY) {
       notifyObservers(Event.STARK_SIGHTED);
     }
   }

event-aggregator/src/main/java/com/iluwatar/event/aggregator/LordVarys.java

@@ -37,7 +37,7 @@ public class LordVarys extends EventEmitter {
 
   @Override
   public void timePasses(Weekday day) {
-    if (day.equals(Weekday.SATURDAY)) {
+    if (day == Weekday.SATURDAY) {
       notifyObservers(Event.TRAITOR_DETECTED);
     }
   }

event-aggregator/src/main/java/com/iluwatar/event/aggregator/Scout.java

@@ -37,7 +37,7 @@ public class Scout extends EventEmitter {
 
   @Override
   public void timePasses(Weekday day) {
-    if (day.equals(Weekday.TUESDAY)) {
+    if (day == Weekday.TUESDAY) {
       notifyObservers(Event.WARSHIPS_APPROACHING);
     }
   }

event-aggregator/src/main/java/com/iluwatar/event/aggregator/Weekday.java

@@ -28,8 +28,13 @@ package com.iluwatar.event.aggregator;
  */
 public enum Weekday {
 
-  MONDAY("Monday"), TUESDAY("Tuesday"), WEDNESDAY("Wednesday"), THURSDAY("Thursday"), FRIDAY(
+  MONDAY("Monday"),
-      "Friday"), SATURDAY("Saturday"), SUNDAY("Sunday");
+  TUESDAY("Tuesday"),
+  WEDNESDAY("Wednesday"),
+  THURSDAY("Thursday"),
+  FRIDAY("Friday"),
+  SATURDAY("Saturday"),
+  SUNDAY("Sunday");
 
   private String description;
 

event-aggregator/src/test/java/com/iluwatar/event/aggregator/AppTest.java

@@ -26,15 +26,12 @@ package com.iluwatar.event.aggregator;
 import org.junit.jupiter.api.Test;
 
 /**
- * 
  * Application test
- *
  */
 public class AppTest {
 
   @Test
   public void test() {
-    String[] args = {};
+    App.main(new String[]{});
-    App.main(args);
   }
 }

event-aggregator/src/test/java/com/iluwatar/event/aggregator/EventEmitterTest.java

@@ -23,8 +23,6 @@
 
 package com.iluwatar.event.aggregator;
 
-import org.junit.jupiter.api.Test;
-
 import static org.mockito.Matchers.eq;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.times;
@@ -35,10 +33,11 @@ import static org.mockito.Mockito.verifyZeroInteractions;
 import java.util.Objects;
 import java.util.function.Function;
 import java.util.function.Supplier;
+import org.junit.jupiter.api.Test;
 
 /**
- * Date: 12/12/15 - 10:58 PM
+ * Date: 12/12/15 - 10:58 PM Tests for Event Emitter
- * Tests for Event Emitter
+ *
  * @param <E> Type of Event Emitter
  * @author Jeroen Meulemeester
  */
@@ -99,13 +98,13 @@ public abstract class EventEmitterTest<E extends EventEmitter> {
   private void testAllDays(final Weekday specialDay, final Event event, final E emitter,
                            final EventObserver... observers) {
 
-    for (final Weekday weekday : Weekday.values()) {
+    for (final var weekday : Weekday.values()) {
       // Pass each week of the day, day by day to the event emitter
       emitter.timePasses(weekday);
 
       if (weekday == specialDay) {
         // On a special day, every observer should have received the event
-        for (final EventObserver observer : observers) {
+        for (final var observer : observers) {
           verify(observer, times(1)).onEvent(eq(event));
         }
       } else {
@@ -126,10 +125,10 @@ public abstract class EventEmitterTest<E extends EventEmitter> {
    * @param event      The expected event emitted by the test object
    */
   private void testAllDaysWithoutDefaultObserver(final Weekday specialDay, final Event event) {
-    final EventObserver observer1 = mock(EventObserver.class);
+    final var observer1 = mock(EventObserver.class);
-    final EventObserver observer2 = mock(EventObserver.class);
+    final var observer2 = mock(EventObserver.class);
 
-    final E emitter = this.factoryWithoutDefaultObserver.get();
+    final var emitter = this.factoryWithoutDefaultObserver.get();
     emitter.registerObserver(observer1);
     emitter.registerObserver(observer2);
 
@@ -143,11 +142,11 @@ public abstract class EventEmitterTest<E extends EventEmitter> {
    * @param event      The expected event emitted by the test object
    */
   private void testAllDaysWithDefaultObserver(final Weekday specialDay, final Event event) {
-    final EventObserver defaultObserver = mock(EventObserver.class);
+    final var defaultObserver = mock(EventObserver.class);
-    final EventObserver observer1 = mock(EventObserver.class);
+    final var observer1 = mock(EventObserver.class);
-    final EventObserver observer2 = mock(EventObserver.class);
+    final var observer2 = mock(EventObserver.class);
 
-    final E emitter = this.factoryWithDefaultObserver.apply(defaultObserver);
+    final var emitter = this.factoryWithDefaultObserver.apply(defaultObserver);
     emitter.registerObserver(observer1);
     emitter.registerObserver(observer2);
 

event-aggregator/src/test/java/com/iluwatar/event/aggregator/EventTest.java

@@ -23,11 +23,12 @@
 
 package com.iluwatar.event.aggregator;
 
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 
+import java.util.Arrays;
+import org.junit.jupiter.api.Test;
+
 /**
  * Date: 12/12/15 - 2:52 PM
  *
@@ -40,11 +41,10 @@ public class EventTest {
    */
   @Test
   public void testToString() {
-    for (final Event event : Event.values()) {
+    Arrays.stream(Event.values()).map(Event::toString).forEach(toString -> {
-      final String toString = event.toString();
       assertNotNull(toString);
       assertFalse(toString.trim().isEmpty());
-    }
+    });
   }
 
 }

event-aggregator/src/test/java/com/iluwatar/event/aggregator/KingJoffreyTest.java

@@ -23,19 +23,19 @@
 
 package com.iluwatar.event.aggregator;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import ch.qos.logback.classic.Logger;
 import ch.qos.logback.classic.spi.ILoggingEvent;
 import ch.qos.logback.core.AppenderBase;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.stream.IntStream;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.slf4j.LoggerFactory;
 
-import java.util.LinkedList;
-import java.util.List;
-
-import static org.junit.jupiter.api.Assertions.assertEquals;
-
 /**
  * Date: 12/12/15 - 3:04 PM
  *
@@ -60,17 +60,16 @@ public class KingJoffreyTest {
    */
   @Test
   public void testOnEvent() {
-    final KingJoffrey kingJoffrey = new KingJoffrey();
+    final var kingJoffrey = new KingJoffrey();
 
-    for (int i = 0; i < Event.values().length; ++i) {
+    IntStream.range(0, Event.values().length).forEach(i -> {
       assertEquals(i, appender.getLogSize());
-      Event event = Event.values()[i];
+      var event = Event.values()[i];
       kingJoffrey.onEvent(event);
-
+      final var expectedMessage = "Received event from the King's Hand: " + event.toString();
-      final String expectedMessage = "Received event from the King's Hand: " + event.toString();
       assertEquals(expectedMessage, appender.getLastMessage());
       assertEquals(i + 1, appender.getLogSize());
-    }
+    });
 
   }
 

event-aggregator/src/test/java/com/iluwatar/event/aggregator/KingsHandTest.java

@@ -23,14 +23,15 @@
 
 package com.iluwatar.event.aggregator;
 
-import org.junit.jupiter.api.Test;
-
 import static org.mockito.Matchers.eq;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
-import static org.mockito.Mockito.verifyZeroInteractions;
 import static org.mockito.Mockito.verifyNoMoreInteractions;
+import static org.mockito.Mockito.verifyZeroInteractions;
+
+import java.util.Arrays;
+import org.junit.jupiter.api.Test;
 
 /**
  * Date: 12/12/15 - 10:57 AM
@@ -47,24 +48,24 @@ public class KingsHandTest extends EventEmitterTest<KingsHand> {
   }
 
   /**
-   * The {@link KingsHand} is both an {@link EventEmitter} as an {@link EventObserver} so verify if every
+   * The {@link KingsHand} is both an {@link EventEmitter} as an {@link EventObserver} so verify if
-   * event received is passed up to it's superior, in most cases {@link KingJoffrey} but now just a
+   * every event received is passed up to it's superior, in most cases {@link KingJoffrey} but now
-   * mocked observer.
+   * just a mocked observer.
    */
   @Test
   public void testPassThrough() throws Exception {
-    final EventObserver observer = mock(EventObserver.class);
+    final var observer = mock(EventObserver.class);
-    final KingsHand kingsHand = new KingsHand(observer);
+    final var kingsHand = new KingsHand(observer);
 
     // The kings hand should not pass any events before he received one
     verifyZeroInteractions(observer);
 
     // Verify if each event is passed on to the observer, nothing less, nothing more.
-    for (final Event event : Event.values()) {
+    Arrays.stream(Event.values()).forEach(event -> {
       kingsHand.onEvent(event);
       verify(observer, times(1)).onEvent(eq(event));
       verifyNoMoreInteractions(observer);
-    }
+    });
 
   }
 

event-aggregator/src/test/java/com/iluwatar/event/aggregator/WeekdayTest.java

@@ -23,11 +23,12 @@
 
 package com.iluwatar.event.aggregator;
 
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 
+import java.util.Arrays;
+import org.junit.jupiter.api.Test;
+
 /**
  * Date: 12/12/15 - 2:12 PM
  *
@@ -37,11 +38,11 @@ public class WeekdayTest {
 
   @Test
   public void testToString() {
-    for (final Weekday weekday : Weekday.values()) {
+    Arrays.stream(Weekday.values()).forEach(weekday -> {
       final String toString = weekday.toString();
       assertNotNull(toString);
       assertEquals(weekday.name(), toString.toUpperCase());
-    }
+    });
   }
 
 }

event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/App.java

@@ -24,7 +24,6 @@
 package com.iluwatar.event.asynchronous;
 
 import java.io.IOException;
-import java.io.InputStream;
 import java.util.Properties;
 import java.util.Scanner;
 import org.slf4j.Logger;
@@ -70,8 +69,7 @@ public class App {
    * @param args command line args
    */
   public static void main(String[] args) {
-    App app = new App();
+    var app = new App();
-
     app.setUp();
     app.run();
   }
@@ -82,9 +80,9 @@ public class App {
    * operations.
    */
   public void setUp() {
-    Properties prop = new Properties();
+    var prop = new Properties();
 
-    InputStream inputStream = App.class.getClassLoader().getResourceAsStream(PROP_FILE_NAME);
+    var inputStream = App.class.getClassLoader().getResourceAsStream(PROP_FILE_NAME);
 
     if (inputStream != null) {
       try {
@@ -92,7 +90,7 @@ public class App {
       } catch (IOException e) {
         LOGGER.error("{} was not found. Defaulting to non-interactive mode.", PROP_FILE_NAME, e);
       }
-      String property = prop.getProperty("INTERACTIVE_MODE");
+      var property = prop.getProperty("INTERACTIVE_MODE");
       if (property.equalsIgnoreCase("YES")) {
         interactiveMode = true;
       }
@@ -114,17 +112,17 @@ public class App {
    * Run program in non-interactive mode.
    */
   public void quickRun() {
-    EventManager eventManager = new EventManager();
+    var eventManager = new EventManager();
 
     try {
       // Create an Asynchronous event.
-      int asyncEventId = eventManager.createAsync(60);
+      var asyncEventId = eventManager.createAsync(60);
       LOGGER.info("Async Event [{}] has been created.", asyncEventId);
       eventManager.start(asyncEventId);
       LOGGER.info("Async Event [{}] has been started.", asyncEventId);
 
       // Create a Synchronous event.
-      int syncEventId = eventManager.create(60);
+      var syncEventId = eventManager.create(60);
       LOGGER.info("Sync Event [{}] has been created.", syncEventId);
       eventManager.start(syncEventId);
       LOGGER.info("Sync Event [{}] has been started.", syncEventId);
@@ -147,10 +145,10 @@ public class App {
    * Run program in interactive mode.
    */
   public void runInteractiveMode() {
-    EventManager eventManager = new EventManager();
+    var eventManager = new EventManager();
 
-    Scanner s = new Scanner(System.in);
+    var s = new Scanner(System.in);
-    int option = -1;
+    var option = -1;
     while (option != 4) {
       LOGGER.info("Hello. Would you like to boil some eggs?");
       LOGGER.info("(1) BOIL AN EGG \n(2) STOP BOILING THIS EGG \n(3) HOW ARE MY EGGS? \n(4) EXIT");
@@ -174,7 +172,7 @@ public class App {
   private void processOption3(EventManager eventManager, Scanner s) {
     s.nextLine();
     LOGGER.info("Just one egg (O) OR all of them (A) ?: ");
-    String eggChoice = s.nextLine();
+    var eggChoice = s.nextLine();
 
     if (eggChoice.equalsIgnoreCase("O")) {
       LOGGER.info("Which egg?: ");
@@ -191,7 +189,7 @@ public class App {
 
   private void processOption2(EventManager eventManager, Scanner s) {
     LOGGER.info("Which egg?: ");
-    int eventId = s.nextInt();
+    var eventId = s.nextInt();
     try {
       eventManager.cancel(eventId);
       LOGGER.info("Egg [{}] is removed from boiler.", eventId);
@@ -203,12 +201,12 @@ public class App {
   private void processOption1(EventManager eventManager, Scanner s) {
     s.nextLine();
     LOGGER.info("Boil multiple eggs at once (A) or boil them one-by-one (S)?: ");
-    String eventType = s.nextLine();
+    var eventType = s.nextLine();
     LOGGER.info("How long should this egg be boiled for (in seconds)?: ");
-    int eventTime = s.nextInt();
+    var eventTime = s.nextInt();
     if (eventType.equalsIgnoreCase("A")) {
       try {
-        int eventId = eventManager.createAsync(eventTime);
+        var eventId = eventManager.createAsync(eventTime);
         eventManager.start(eventId);
         LOGGER.info("Egg [{}] is being boiled.", eventId);
       } catch (MaxNumOfEventsAllowedException | LongRunningEventException
@@ -217,7 +215,7 @@ public class App {
       }
     } else if (eventType.equalsIgnoreCase("S")) {
       try {
-        int eventId = eventManager.create(eventTime);
+        var eventId = eventManager.create(eventTime);
         eventManager.start(eventId);
         LOGGER.info("Egg [{}] is being boiled.", eventId);
       } catch (MaxNumOfEventsAllowedException | InvalidOperationException

event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/Event.java

@@ -82,8 +82,8 @@ public class Event implements IEvent, Runnable {
 
   @Override
   public void run() {
-    long currentTime = System.currentTimeMillis();
+    var currentTime = System.currentTimeMillis();
-    long endTime = currentTime + (eventTime * 1000);
+    var endTime = currentTime + (eventTime * 1000);
     while (System.currentTimeMillis() < endTime) {
       try {
         Thread.sleep(1000); // Sleep for 1 second.

event-asynchronous/src/main/java/com/iluwatar/event/asynchronous/EventManager.java

@@ -23,7 +23,6 @@
 
 package com.iluwatar.event.asynchronous;
 
-import java.util.Iterator;
 import java.util.Map;
 import java.util.Random;
 import java.util.concurrent.ConcurrentHashMap;
@@ -75,7 +74,7 @@ public class EventManager implements ThreadCompleteListener {
           + " running. Please wait until it finishes and try again.");
     }
 
-    int eventId = createEvent(eventTime, true);
+    var eventId = createEvent(eventTime, true);
     currentlyRunningSyncEvent = eventId;
 
     return eventId;
@@ -106,9 +105,9 @@ public class EventManager implements ThreadCompleteListener {
           "Maximum event time allowed is " + MAX_EVENT_TIME + " seconds. Please try again.");
     }
 
-    int newEventId = generateId();
+    var newEventId = generateId();
 
-    Event newEvent = new Event(newEventId, eventTime, isSynchronous);
+    var newEvent = new Event(newEventId, eventTime, isSynchronous);
     newEvent.addListener(this);
     eventPool.put(newEventId, newEvent);
 
@@ -167,11 +166,7 @@ public class EventManager implements ThreadCompleteListener {
    */
   @SuppressWarnings("rawtypes")
   public void statusOfAllEvents() {
-    Iterator it = eventPool.entrySet().iterator();
+    eventPool.entrySet().forEach(entry -> ((Event) ((Map.Entry) entry).getValue()).status());
-    while (it.hasNext()) {
-      Map.Entry pair = (Map.Entry) it.next();
-      ((Event) pair.getValue()).status();
-    }
   }
 
   /**
@@ -179,11 +174,7 @@ public class EventManager implements ThreadCompleteListener {
    */
   @SuppressWarnings("rawtypes")
   public void shutdown() {
-    Iterator it = eventPool.entrySet().iterator();
+    eventPool.entrySet().forEach(entry -> ((Event) ((Map.Entry) entry).getValue()).stop());
-    while (it.hasNext()) {
-      Map.Entry pair = (Map.Entry) it.next();
-      ((Event) pair.getValue()).stop();
-    }
   }
 
   /**
@@ -194,7 +185,7 @@ public class EventManager implements ThreadCompleteListener {
   private int generateId() {
     // nextInt is normally exclusive of the top value,
     // so add 1 to make it inclusive
-    int randomNum = rand.nextInt((MAX_ID - MIN_ID) + 1) + MIN_ID;
+    var randomNum = rand.nextInt((MAX_ID - MIN_ID) + 1) + MIN_ID;
     while (eventPool.containsKey(randomNum)) {
       randomNum = rand.nextInt((MAX_ID - MIN_ID) + 1) + MIN_ID;
     }

event-asynchronous/src/test/java/com/iluwatar/event/asynchronous/AppTest.java

@@ -25,15 +25,12 @@ package com.iluwatar.event.asynchronous;
 
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
-
 /**
  * Tests that EventAsynchronous example runs without errors.
  */
 public class AppTest {
   @Test
-  public void test() throws IOException {
+  public void test() {
-    String[] args = {};
+    App.main(new String[]{});
-    App.main(args);
   }
 }

event-asynchronous/src/test/java/com/iluwatar/event/asynchronous/EventAsynchronousTest.java

@@ -23,28 +23,26 @@
 
 package com.iluwatar.event.asynchronous;
 
-import org.junit.jupiter.api.Test;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotEquals;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import org.junit.jupiter.api.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 /**
- *
  * Application test
- *
  */
 public class EventAsynchronousTest {
   private static final Logger LOGGER = LoggerFactory.getLogger(EventAsynchronousTest.class);
 
   @Test
   public void testAsynchronousEvent() {
-    EventManager eventManager = new EventManager();
+    var eventManager = new EventManager();
     try {
-      int aEventId = eventManager.createAsync(60);
+      var aEventId = eventManager.createAsync(60);
       eventManager.start(aEventId);
       assertEquals(1, eventManager.getEventPool().size());
       assertTrue(eventManager.getEventPool().size() < EventManager.MAX_RUNNING_EVENTS);
@@ -58,9 +56,9 @@ public class EventAsynchronousTest {
 
   @Test
   public void testSynchronousEvent() {
-    EventManager eventManager = new EventManager();
+    var eventManager = new EventManager();
     try {
-      int sEventId = eventManager.create(60);
+      var sEventId = eventManager.create(60);
       eventManager.start(sEventId);
       assertEquals(1, eventManager.getEventPool().size());
       assertTrue(eventManager.getEventPool().size() < EventManager.MAX_RUNNING_EVENTS);
@@ -76,9 +74,9 @@ public class EventAsynchronousTest {
   @Test
   public void testUnsuccessfulSynchronousEvent() {
     assertThrows(InvalidOperationException.class, () -> {
-      EventManager eventManager = new EventManager();
+      var eventManager = new EventManager();
       try {
-        int sEventId = eventManager.create(60);
+        var sEventId = eventManager.create(60);
         eventManager.start(sEventId);
         sEventId = eventManager.create(60);
         eventManager.start(sEventId);
@@ -90,20 +88,18 @@ public class EventAsynchronousTest {
 
   @Test
   public void testFullSynchronousEvent() {
-    EventManager eventManager = new EventManager();
+    var eventManager = new EventManager();
     try {
-      int eventTime = 1;
+      var eventTime = 1;
 
-      int sEventId = eventManager.create(eventTime);
+      var sEventId = eventManager.create(eventTime);
       assertEquals(1, eventManager.getEventPool().size());
       eventManager.start(sEventId);
 
-      long currentTime = System.currentTimeMillis();
+      var currentTime = System.currentTimeMillis();
-      long endTime = currentTime + (eventTime + 2 * 1000); // +2 to give a bit of buffer time for event to
+      // +2 to give a bit of buffer time for event to complete properly.
-                                                           // complete
+      var endTime = currentTime + (eventTime + 2 * 1000);
-      // properly.
+      while (System.currentTimeMillis() < endTime) ;
-      while (System.currentTimeMillis() < endTime) {
-      }
 
       assertTrue(eventManager.getEventPool().isEmpty());
 
@@ -115,24 +111,23 @@ public class EventAsynchronousTest {
 
   @Test
   public void testFullAsynchronousEvent() {
-    EventManager eventManager = new EventManager();
+    var eventManager = new EventManager();
     try {
-      int eventTime = 1;
+      var eventTime = 1;
 
-      int aEventId1 = eventManager.createAsync(eventTime);
+      var aEventId1 = eventManager.createAsync(eventTime);
-      int aEventId2 = eventManager.createAsync(eventTime);
+      var aEventId2 = eventManager.createAsync(eventTime);
-      int aEventId3 = eventManager.createAsync(eventTime);
+      var aEventId3 = eventManager.createAsync(eventTime);
       assertEquals(3, eventManager.getEventPool().size());
 
       eventManager.start(aEventId1);
       eventManager.start(aEventId2);
       eventManager.start(aEventId3);
 
-      long currentTime = System.currentTimeMillis();
+      var currentTime = System.currentTimeMillis();
-      long endTime = currentTime + (eventTime + 2 * 1000); // +2 to give a bit of buffer time for event to complete
+      // +2 to give a bit of buffer time for event to complete properly.
-                                                           // properly.
+      var endTime = currentTime + (eventTime + 2 * 1000);
-      while (System.currentTimeMillis() < endTime) {
+      while (System.currentTimeMillis() < endTime) ;
-      }
 
       assertTrue(eventManager.getEventPool().isEmpty());
 

event-driven-architecture/src/main/java/com/iluwatar/eda/App.java

@@ -52,11 +52,11 @@ public class App {
    */
   public static void main(String[] args) {
 
-    EventDispatcher dispatcher = new EventDispatcher();
+    var dispatcher = new EventDispatcher();
     dispatcher.registerHandler(UserCreatedEvent.class, new UserCreatedEventHandler());
     dispatcher.registerHandler(UserUpdatedEvent.class, new UserUpdatedEventHandler());
 
-    User user = new User("iluwatar");
+    var user = new User("iluwatar");
     dispatcher.dispatch(new UserCreatedEvent(user));
     dispatcher.dispatch(new UserUpdatedEvent(user));
   }

event-driven-architecture/src/main/java/com/iluwatar/eda/framework/EventDispatcher.java

@@ -44,8 +44,10 @@ public class EventDispatcher {
    * @param eventType The {@link Event} to be registered
    * @param handler   The {@link Handler} that will be handling the {@link Event}
    */
-  public <E extends Event> void registerHandler(Class<E> eventType,
+  public <E extends Event> void registerHandler(
-                                                Handler<E> handler) {
+      Class<E> eventType,
+      Handler<E> handler
+  ) {
     handlers.put(eventType, handler);
   }
 
@@ -56,7 +58,7 @@ public class EventDispatcher {
    */
   @SuppressWarnings("unchecked")
   public <E extends Event> void dispatch(E event) {
-    Handler<E> handler = (Handler<E>) handlers.get(event.getClass());
+    var handler = (Handler<E>) handlers.get(event.getClass());
     if (handler != null) {
       handler.onEvent(event);
     }

event-driven-architecture/src/test/java/com/iluwatar/eda/AppTest.java

@@ -25,15 +25,12 @@ package com.iluwatar.eda;
 
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
-
 /**
  * Tests that Event Driven Architecture example runs without errors.
  */
 public class AppTest {
   @Test
-  public void test() throws IOException {
+  public void test() {
-    String[] args = {};
+    App.main(new String[]{});
-    App.main(args);
   }
 }

event-driven-architecture/src/test/java/com/iluwatar/eda/event/UserCreatedEventTest.java

@@ -23,11 +23,11 @@
 
 package com.iluwatar.eda.event;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import com.iluwatar.eda.model.User;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-
 /**
  * {@link UserCreatedEventTest} tests and verifies {@link AbstractEvent} behaviour.
  */
@@ -39,8 +39,8 @@ public class UserCreatedEventTest {
    */
   @Test
   public void testGetEventType() {
-    User user = new User("iluwatar");
+    var user = new User("iluwatar");
-    UserCreatedEvent userCreatedEvent = new UserCreatedEvent(user);
+    var userCreatedEvent = new UserCreatedEvent(user);
     assertEquals(UserCreatedEvent.class, userCreatedEvent.getType());
   }
 }

event-driven-architecture/src/test/java/com/iluwatar/eda/framework/EventDispatcherTest.java

@@ -23,6 +23,9 @@
 
 package com.iluwatar.eda.framework;
 
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.verify;
+
 import com.iluwatar.eda.event.UserCreatedEvent;
 import com.iluwatar.eda.event.UserUpdatedEvent;
 import com.iluwatar.eda.handler.UserCreatedEventHandler;
@@ -30,9 +33,6 @@ import com.iluwatar.eda.handler.UserUpdatedEventHandler;
 import com.iluwatar.eda.model.User;
 import org.junit.jupiter.api.Test;
 
-import static org.mockito.Mockito.spy;
-import static org.mockito.Mockito.verify;
-
 /**
  * Event Dispatcher unit tests to assert and verify correct event dispatcher behaviour
  */
@@ -45,16 +45,16 @@ public class EventDispatcherTest {
   @Test
   public void testEventDriverPattern() {
 
-    EventDispatcher dispatcher = spy(new EventDispatcher());
+    var dispatcher = spy(new EventDispatcher());
-    UserCreatedEventHandler userCreatedEventHandler = spy(new UserCreatedEventHandler());
+    var userCreatedEventHandler = spy(new UserCreatedEventHandler());
-    UserUpdatedEventHandler userUpdatedEventHandler = spy(new UserUpdatedEventHandler());
+    var userUpdatedEventHandler = spy(new UserUpdatedEventHandler());
     dispatcher.registerHandler(UserCreatedEvent.class, userCreatedEventHandler);
     dispatcher.registerHandler(UserUpdatedEvent.class, userUpdatedEventHandler);
 
-    User user = new User("iluwatar");
+    var user = new User("iluwatar");
 
-    UserCreatedEvent userCreatedEvent = new UserCreatedEvent(user);
+    var userCreatedEvent = new UserCreatedEvent(user);
-    UserUpdatedEvent userUpdatedEvent = new UserUpdatedEvent(user);
+    var userUpdatedEvent = new UserUpdatedEvent(user);
 
     //fire a userCreatedEvent and verify that userCreatedEventHandler has been invoked.
     dispatcher.dispatch(userCreatedEvent);

event-queue/src/main/java/com/iluwatar/event/queue/App.java

@@ -53,12 +53,12 @@ public class App {
    */
   public static void main(String[] args) throws UnsupportedAudioFileException, IOException,
       InterruptedException {
-    Audio audio = Audio.getInstance();
+    var audio = Audio.getInstance();
     audio.playSound(audio.getAudioStream("./etc/Bass-Drum-1.wav"), -10.0f);
     audio.playSound(audio.getAudioStream("./etc/Closed-Hi-Hat-1.wav"), -8.0f);
 
     LOGGER.info("Press Enter key to stop the program...");
-    try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in))) {
+    try (var br = new BufferedReader(new InputStreamReader(System.in))) {
       br.read();
     }
     audio.stopService();

event-queue/src/main/java/com/iluwatar/event/queue/Audio.java

@@ -27,7 +27,6 @@ import java.io.File;
 import java.io.IOException;
 import javax.sound.sampled.AudioInputStream;
 import javax.sound.sampled.AudioSystem;
-import javax.sound.sampled.Clip;
 import javax.sound.sampled.LineUnavailableException;
 import javax.sound.sampled.UnsupportedAudioFileException;
 import org.slf4j.Logger;
@@ -116,10 +115,11 @@ public class Audio {
   public void playSound(AudioInputStream stream, float volume) {
     init();
     // Walk the pending requests.
-    for (int i = headIndex; i != tailIndex; i = (i + 1) % MAX_PENDING) {
+    for (var i = headIndex; i != tailIndex; i = (i + 1) % MAX_PENDING) {
-      if (getPendingAudio()[i].getStream() == stream) {
+      var playMessage = getPendingAudio()[i];
+      if (playMessage.getStream() == stream) {
         // Use the larger of the two volumes.
-        getPendingAudio()[i].setVolume(Math.max(volume, getPendingAudio()[i].getVolume()));
+        playMessage.setVolume(Math.max(volume, playMessage.getVolume()));
 
         // Don't need to enqueue.
         return;
@@ -137,11 +137,10 @@ public class Audio {
     if (headIndex == tailIndex) {
       return;
     }
-    Clip clip = null;
     try {
-      AudioInputStream audioStream = getPendingAudio()[headIndex].getStream();
+      var audioStream = getPendingAudio()[headIndex].getStream();
       headIndex++;
-      clip = AudioSystem.getClip();
+      var clip = AudioSystem.getClip();
       clip.open(audioStream);
       clip.start();
     } catch (LineUnavailableException e) {

event-sourcing/src/main/java/com/iluwatar/event/sourcing/app/App.java

@@ -69,7 +69,7 @@ public class App {
    */
   public static void main(String[] args) {
 
-    DomainEventProcessor eventProcessor = new DomainEventProcessor();
+    var eventProcessor = new DomainEventProcessor();
 
 
     LOGGER.info("Running the system first time............");

event-sourcing/src/main/java/com/iluwatar/event/sourcing/domain/Account.java

@@ -104,7 +104,7 @@ public class Account {
    * @return the account
    */
   public Account copy() {
-    Account account = new Account(accountNo, owner);
+    var account = new Account(accountNo, owner);
     account.setMoney(money);
     return account;
   }
@@ -135,7 +135,7 @@ public class Account {
   }
 
   private void handleWithdrawal(BigDecimal money, boolean realTime) {
-    if (this.money.compareTo(money) == -1) {
+    if (this.money.compareTo(money) < 0) {
       throw new RuntimeException("Insufficient Account Balance");
     }
 

event-sourcing/src/main/java/com/iluwatar/event/sourcing/event/AccountCreateEvent.java

@@ -72,7 +72,7 @@ public class AccountCreateEvent extends DomainEvent {
 
   @Override
   public void process() {
-    Account account = AccountAggregate.getAccount(accountNo);
+    var account = AccountAggregate.getAccount(accountNo);
     if (account != null) {
       throw new RuntimeException("Account already exists");
     }

event-sourcing/src/main/java/com/iluwatar/event/sourcing/event/MoneyDepositEvent.java

@@ -23,9 +23,9 @@
 
 package com.iluwatar.event.sourcing.event;
 
-import com.iluwatar.event.sourcing.domain.Account;
 import com.iluwatar.event.sourcing.state.AccountAggregate;
 import java.math.BigDecimal;
+import java.util.Optional;
 
 /**
  * This is the class that implements money deposit event. Holds the necessary info for a money
@@ -73,10 +73,8 @@ public class MoneyDepositEvent extends DomainEvent {
 
   @Override
   public void process() {
-    Account account = AccountAggregate.getAccount(accountNo);
+    var account = Optional.ofNullable(AccountAggregate.getAccount(accountNo))
-    if (account == null) {
+        .orElseThrow(() -> new RuntimeException("Account not found"));
-      throw new RuntimeException("Account not found");
-    }
     account.handleEvent(this);
   }
 }

event-sourcing/src/main/java/com/iluwatar/event/sourcing/event/MoneyTransferEvent.java

@@ -23,9 +23,9 @@
 
 package com.iluwatar.event.sourcing.event;
 
-import com.iluwatar.event.sourcing.domain.Account;
 import com.iluwatar.event.sourcing.state.AccountAggregate;
 import java.math.BigDecimal;
+import java.util.Optional;
 
 /**
  * This is the class that implements money transfer event. Holds the necessary info for a money
@@ -86,15 +86,10 @@ public class MoneyTransferEvent extends DomainEvent {
 
   @Override
   public void process() {
-    Account accountFrom = AccountAggregate.getAccount(accountNoFrom);
+    var accountFrom = Optional.ofNullable(AccountAggregate.getAccount(accountNoFrom))
-    if (accountFrom == null) {
+        .orElseThrow(() -> new RuntimeException("Account not found " + accountNoFrom));
-      throw new RuntimeException("Account not found " + accountNoFrom);
+    var accountTo = Optional.ofNullable(AccountAggregate.getAccount(accountNoTo))
-    }
+        .orElseThrow(() -> new RuntimeException("Account not found " + accountNoTo));
-    Account accountTo = AccountAggregate.getAccount(accountNoTo);
-    if (accountTo == null) {
-      throw new RuntimeException("Account not found " + accountNoTo);
-    }
-
     accountFrom.handleTransferFromEvent(this);
     accountTo.handleTransferToEvent(this);
   }

event-sourcing/src/main/java/com/iluwatar/event/sourcing/processor/DomainEventProcessor.java

@@ -57,13 +57,8 @@ public class DomainEventProcessor {
    */
   public void recover() {
     DomainEvent domainEvent;
-    while (true) {
+    while ((domainEvent = processorJournal.readNext()) != null) {
-      domainEvent = processorJournal.readNext();
+      domainEvent.process();
-      if (domainEvent == null) {
-        break;
-      } else {
-        domainEvent.process();
-      }
     }
   }
 }

event-sourcing/src/main/java/com/iluwatar/event/sourcing/processor/JsonFileJournal.java

@@ -38,7 +38,7 @@ import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.OutputStreamWriter;
-import java.io.Writer;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -60,8 +60,8 @@ public class JsonFileJournal {
   public JsonFileJournal() {
     file = new File("Journal.json");
     if (file.exists()) {
-      try (BufferedReader input = new BufferedReader(
+      try (var input = new BufferedReader(
-          new InputStreamReader(new FileInputStream(file), "UTF-8"))) {
+          new InputStreamReader(new FileInputStream(file), StandardCharsets.UTF_8))) {
         String line;
         while ((line = input.readLine()) != null) {
           events.add(line);
@@ -81,7 +81,7 @@ public class JsonFileJournal {
    * @param domainEvent the domain event
    */
   public void write(DomainEvent domainEvent) {
-    Gson gson = new Gson();
+    var gson = new Gson();
     JsonElement jsonElement;
     if (domainEvent instanceof AccountCreateEvent) {
       jsonElement = gson.toJsonTree(domainEvent, AccountCreateEvent.class);
@@ -93,9 +93,9 @@ public class JsonFileJournal {
       throw new RuntimeException("Journal Event not recegnized");
     }
 
-    try (Writer output = new BufferedWriter(
+    try (var output = new BufferedWriter(
-        new OutputStreamWriter(new FileOutputStream(file, true), "UTF-8"))) {
+        new OutputStreamWriter(new FileOutputStream(file, true), StandardCharsets.UTF_8))) {
-      String eventString = jsonElement.toString();
+      var eventString = jsonElement.toString();
       output.write(eventString + "\r\n");
     } catch (IOException e) {
       throw new RuntimeException(e);
@@ -120,13 +120,13 @@ public class JsonFileJournal {
     if (index >= events.size()) {
       return null;
     }
-    String event = events.get(index);
+    var event = events.get(index);
     index++;
 
-    JsonParser parser = new JsonParser();
+    var parser = new JsonParser();
-    JsonElement jsonElement = parser.parse(event);
+    var jsonElement = parser.parse(event);
-    String eventClassName = jsonElement.getAsJsonObject().get("eventClassName").getAsString();
+    var eventClassName = jsonElement.getAsJsonObject().get("eventClassName").getAsString();
-    Gson gson = new Gson();
+    var gson = new Gson();
     DomainEvent domainEvent;
     if (eventClassName.equals("AccountCreateEvent")) {
       domainEvent = gson.fromJson(jsonElement, AccountCreateEvent.class);

event-sourcing/src/main/java/com/iluwatar/event/sourcing/state/AccountAggregate.java

@@ -26,6 +26,7 @@ package com.iluwatar.event.sourcing.state;
 import com.iluwatar.event.sourcing.domain.Account;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Optional;
 
 /**
  * This is the static accounts map holder class. This class holds the state of the accounts.
@@ -55,11 +56,10 @@ public class AccountAggregate {
    * @return the copy of the account or null if not found
    */
   public static Account getAccount(int accountNo) {
-    Account account = accounts.get(accountNo);
+    return Optional.of(accountNo)
-    if (account == null) {
+        .map(accounts::get)
-      return null;
+        .map(Account::copy)
-    }
+        .orElse(null);
-    return account.copy();
   }
 
   /**

event-sourcing/src/test/java/IntegrationTest.java

@@ -21,25 +21,23 @@
  * THE SOFTWARE.
  */
 
-import com.iluwatar.event.sourcing.domain.Account;
+import static com.iluwatar.event.sourcing.app.App.ACCOUNT_OF_DAENERYS;
+import static com.iluwatar.event.sourcing.app.App.ACCOUNT_OF_JON;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 import com.iluwatar.event.sourcing.event.AccountCreateEvent;
 import com.iluwatar.event.sourcing.event.MoneyDepositEvent;
 import com.iluwatar.event.sourcing.event.MoneyTransferEvent;
 import com.iluwatar.event.sourcing.processor.DomainEventProcessor;
 import com.iluwatar.event.sourcing.state.AccountAggregate;
+import java.math.BigDecimal;
+import java.util.Date;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import java.math.BigDecimal;
-import java.util.Date;
-
-import static com.iluwatar.event.sourcing.app.App.ACCOUNT_OF_DAENERYS;
-import static com.iluwatar.event.sourcing.app.App.ACCOUNT_OF_JON;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-
 /**
  * Intergartion Test for Event Sourcing state recovery
- *
+ * <p>
  * Created by Serdar Hamzaogullari on 19.08.2017.
  */
 public class IntegrationTest {
@@ -71,25 +69,25 @@ public class IntegrationTest {
         1, new Date().getTime(), ACCOUNT_OF_JON, "Jon Snow"));
 
     eventProcessor.process(new MoneyDepositEvent(
-        2, new Date().getTime(), ACCOUNT_OF_DAENERYS,  new BigDecimal("100000")));
+        2, new Date().getTime(), ACCOUNT_OF_DAENERYS, new BigDecimal("100000")));
 
     eventProcessor.process(new MoneyDepositEvent(
-        3, new Date().getTime(), ACCOUNT_OF_JON,  new BigDecimal("100")));
+        3, new Date().getTime(), ACCOUNT_OF_JON, new BigDecimal("100")));
 
     eventProcessor.process(new MoneyTransferEvent(
         4, new Date().getTime(), new BigDecimal("10000"), ACCOUNT_OF_DAENERYS,
         ACCOUNT_OF_JON));
 
-    Account accountOfDaenerysBeforeShotDown = AccountAggregate.getAccount(ACCOUNT_OF_DAENERYS);
+    var accountOfDaenerysBeforeShotDown = AccountAggregate.getAccount(ACCOUNT_OF_DAENERYS);
-    Account accountOfJonBeforeShotDown = AccountAggregate.getAccount(ACCOUNT_OF_JON);
+    var accountOfJonBeforeShotDown = AccountAggregate.getAccount(ACCOUNT_OF_JON);
 
     AccountAggregate.resetState();
 
     eventProcessor = new DomainEventProcessor();
     eventProcessor.recover();
 
-    Account accountOfDaenerysAfterShotDown = AccountAggregate.getAccount(ACCOUNT_OF_DAENERYS);
+    var accountOfDaenerysAfterShotDown = AccountAggregate.getAccount(ACCOUNT_OF_DAENERYS);
-    Account accountOfJonAfterShotDown = AccountAggregate.getAccount(ACCOUNT_OF_JON);
+    var accountOfJonAfterShotDown = AccountAggregate.getAccount(ACCOUNT_OF_JON);
 
     assertEquals(accountOfDaenerysBeforeShotDown.getMoney(),
         accountOfDaenerysAfterShotDown.getMoney());

execute-around/src/main/java/com/iluwatar/execute/around/SimpleFileWriter.java

@@ -36,7 +36,7 @@ public class SimpleFileWriter {
    * Constructor.
    */
   public SimpleFileWriter(String filename, FileWriterAction action) throws IOException {
-    try (FileWriter writer = new FileWriter(filename)) {
+    try (var writer = new FileWriter(filename)) {
       action.writeFile(writer);
     }
   }

execute-around/src/test/java/com/iluwatar/execute/around/AppTest.java

@@ -23,30 +23,26 @@
 
 package com.iluwatar.execute.around;
 
+import java.io.File;
+import java.io.IOException;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import java.io.File;
-import java.io.IOException;
-
 /**
- * 
  * Tests execute-around example.
- *
  */
 public class AppTest {
 
   @Test
   public void test() throws IOException {
-    String[] args = {};
+    App.main(new String[]{});
-    App.main(args);
   }
 
   @BeforeEach
   @AfterEach
   public void cleanup() {
-    File file = new File("testfile.txt");
+    var file = new File("testfile.txt");
     file.delete();
   }
 }

execute-around/src/test/java/com/iluwatar/execute/around/SimpleFileWriterTest.java

@@ -23,20 +23,19 @@
 
 package com.iluwatar.execute.around;
 
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
 import org.junit.Rule;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.migrationsupport.rules.EnableRuleMigrationSupport;
 import org.junit.rules.TemporaryFolder;
 
-import java.io.File;
-import java.io.IOException;
-import java.nio.file.Files;
-
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 /**
  * Date: 12/12/15 - 3:21 PM
  *
@@ -50,13 +49,13 @@ public class SimpleFileWriterTest {
 
   @Test
   public void testWriterNotNull() throws Exception {
-    final File temporaryFile = this.testFolder.newFile();
+    final var temporaryFile = this.testFolder.newFile();
     new SimpleFileWriter(temporaryFile.getPath(), Assertions::assertNotNull);
   }
 
   @Test
   public void testCreatesNonExistentFile() throws Exception {
-    final File nonExistingFile = new File(this.testFolder.getRoot(), "non-existing-file");
+    final var nonExistingFile = new File(this.testFolder.getRoot(), "non-existing-file");
     assertFalse(nonExistingFile.exists());
 
     new SimpleFileWriter(nonExistingFile.getPath(), Assertions::assertNotNull);
@@ -65,9 +64,9 @@ public class SimpleFileWriterTest {
 
   @Test
   public void testContentsAreWrittenToFile() throws Exception {
-    final String testMessage = "Test message";
+    final var testMessage = "Test message";
 
-    final File temporaryFile = this.testFolder.newFile();
+    final var temporaryFile = this.testFolder.newFile();
     assertTrue(temporaryFile.exists());
 
     new SimpleFileWriter(temporaryFile.getPath(), writer -> writer.write(testMessage));
@@ -76,9 +75,9 @@ public class SimpleFileWriterTest {
 
   @Test
   public void testRipplesIoExceptionOccurredWhileWriting() {
-    String message = "Some error";
+    var message = "Some error";
     assertThrows(IOException.class, () -> {
-      final File temporaryFile = this.testFolder.newFile();
+      final var temporaryFile = this.testFolder.newFile();
       new SimpleFileWriter(temporaryFile.getPath(), writer -> {
         throw new IOException(message);
       });

extension-objects/src/main/java/App.java

@@ -24,7 +24,8 @@
 import abstractextensions.CommanderExtension;
 import abstractextensions.SergeantExtension;
 import abstractextensions.SoldierExtension;
-import org.slf4j.Logger;
+import java.util.Optional;
+import java.util.function.Function;
 import org.slf4j.LoggerFactory;
 import units.CommanderUnit;
 import units.SergeantUnit;
@@ -45,9 +46,9 @@ public class App {
   public static void main(String[] args) {
 
     //Create 3 different units
-    Unit soldierUnit = new SoldierUnit("SoldierUnit1");
+    var soldierUnit = new SoldierUnit("SoldierUnit1");
-    Unit sergeantUnit = new SergeantUnit("SergeantUnit1");
+    var sergeantUnit = new SergeantUnit("SergeantUnit1");
-    Unit commanderUnit = new CommanderUnit("CommanderUnit1");
+    var commanderUnit = new CommanderUnit("CommanderUnit1");
 
     //check for each unit to have an extension
     checkExtensionsForUnit(soldierUnit);
@@ -57,32 +58,24 @@ public class App {
   }
 
   private static void checkExtensionsForUnit(Unit unit) {
-    final Logger logger = LoggerFactory.getLogger(App.class);
+    final var logger = LoggerFactory.getLogger(App.class);
 
-    SoldierExtension soldierExtension =
+    var name = unit.getName();
-        (SoldierExtension) unit.getUnitExtension("SoldierExtension");
+    Function<String, Runnable> func = (e) -> () -> logger.info(name + " without " + e);
-    SergeantExtension sergeantExtension =
-        (SergeantExtension) unit.getUnitExtension("SergeantExtension");
-    CommanderExtension commanderExtension =
-        (CommanderExtension) unit.getUnitExtension("CommanderExtension");
 
-    //if unit have extension call the method
+    var extension = "SoldierExtension";
-    if (soldierExtension != null) {
+    Optional.ofNullable(unit.getUnitExtension(extension))
-      soldierExtension.soldierReady();
+        .map(e -> (SoldierExtension) e)
-    } else {
+        .ifPresentOrElse(SoldierExtension::soldierReady, func.apply(extension));
-      logger.info(unit.getName() + " without SoldierExtension");
-    }
 
-    if (sergeantExtension != null) {
+    extension = "SergeantExtension";
-      sergeantExtension.sergeantReady();
+    Optional.ofNullable(unit.getUnitExtension(extension))
-    } else {
+        .map(e -> (SergeantExtension) e)
-      logger.info(unit.getName() + " without SergeantExtension");
+        .ifPresentOrElse(SergeantExtension::sergeantReady, func.apply(extension));
-    }
 
-    if (commanderExtension != null) {
+    extension = "CommanderExtension";
-      commanderExtension.commanderReady();
+    Optional.ofNullable(unit.getUnitExtension(extension))
-    } else {
+        .map(e -> (CommanderExtension) e)
-      logger.info(unit.getName() + " without CommanderExtension");
+        .ifPresentOrElse(CommanderExtension::commanderReady, func.apply(extension));
-    }
   }
 }

extension-objects/src/main/java/units/CommanderUnit.java

@@ -25,6 +25,7 @@ package units;
 
 import abstractextensions.UnitExtension;
 import concreteextensions.Commander;
+import java.util.Optional;
 
 /**
  * Class defining CommanderUnit.
@@ -39,10 +40,7 @@ public class CommanderUnit extends Unit {
   public UnitExtension getUnitExtension(String extensionName) {
 
     if (extensionName.equals("CommanderExtension")) {
-      if (unitExtension == null) {
+      return Optional.ofNullable(unitExtension).orElseGet(() -> new Commander(this));
-        unitExtension = new Commander(this);
-      }
-      return unitExtension;
     }
 
     return super.getUnitExtension(extensionName);

extension-objects/src/main/java/units/SergeantUnit.java

@@ -25,6 +25,7 @@ package units;
 
 import abstractextensions.UnitExtension;
 import concreteextensions.Sergeant;
+import java.util.Optional;
 
 /**
  * Class defining SergeantUnit.
@@ -39,10 +40,7 @@ public class SergeantUnit extends Unit {
   public UnitExtension getUnitExtension(String extensionName) {
 
     if (extensionName.equals("SergeantExtension")) {
-      if (unitExtension == null) {
+      return Optional.ofNullable(unitExtension).orElseGet(() -> new Sergeant(this));
-        unitExtension = new Sergeant(this);
-      }
-      return unitExtension;
     }
 
     return super.getUnitExtension(extensionName);

extension-objects/src/main/java/units/SoldierUnit.java

@@ -25,6 +25,7 @@ package units;
 
 import abstractextensions.UnitExtension;
 import concreteextensions.Soldier;
+import java.util.Optional;
 
 /**
  * Class defining SoldierUnit.
@@ -39,12 +40,9 @@ public class SoldierUnit extends Unit {
   public UnitExtension getUnitExtension(String extensionName) {
 
     if (extensionName.equals("SoldierExtension")) {
-      if (unitExtension == null) {
+      return Optional.ofNullable(unitExtension).orElseGet(() -> new Soldier(this));
-        unitExtension = new Soldier(this);
-      }
-
-      return unitExtension;
     }
+
     return super.getUnitExtension(extensionName);
   }
 }

extension-objects/src/test/java/AppTest.java

@@ -28,10 +28,8 @@ import org.junit.jupiter.api.Test;
  */
 public class AppTest {
   @Test
-  public void main() throws Exception {
+  public void main() {
-
+    App.main(new String[]{});
-    String[] args = {};
-    App.main(args);
   }
 
 }

extension-objects/src/test/java/concreteextensions/CommanderTest.java

@@ -32,8 +32,7 @@ import units.CommanderUnit;
 public class CommanderTest {
   @Test
   public void commanderReady() {
-    final Commander commander = new Commander(new CommanderUnit("CommanderUnitTest"));
+    final var commander = new Commander(new CommanderUnit("CommanderUnitTest"));
-
     commander.commanderReady();
   }
 

extension-objects/src/test/java/concreteextensions/SergeantTest.java

@@ -31,9 +31,8 @@ import units.SergeantUnit;
  */
 public class SergeantTest {
   @Test
-  public void sergeantReady() throws Exception {
+  public void sergeantReady() {
-    final Sergeant sergeant = new Sergeant(new SergeantUnit("SergeantUnitTest"));
+    final var sergeant = new Sergeant(new SergeantUnit("SergeantUnitTest"));
-
     sergeant.sergeantReady();
   }
 

extension-objects/src/test/java/concreteextensions/SoldierTest.java

@@ -31,9 +31,8 @@ import units.SoldierUnit;
  */
 public class SoldierTest {
   @Test
-  public void soldierReady() throws Exception {
+  public void soldierReady() {
-    final Soldier soldier = new Soldier(new SoldierUnit("SoldierUnitTest"));
+    final var soldier = new Soldier(new SoldierUnit("SoldierUnitTest"));
-
     soldier.soldierReady();
   }
 

extension-objects/src/test/java/units/CommanderUnitTest.java

@@ -23,20 +23,18 @@
 
 package units;
 
-import abstractextensions.CommanderExtension;
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertNull;
 
+import org.junit.jupiter.api.Test;
+
 /**
  * Created by Srdjan on 03-May-17.
  */
 public class CommanderUnitTest {
   @Test
   public void getUnitExtension() {
-
+    final var unit = new CommanderUnit("CommanderUnitName");
-    final Unit unit = new CommanderUnit("CommanderUnitName");
 
     assertNull(unit.getUnitExtension("SoldierExtension"));
     assertNull(unit.getUnitExtension("SergeantExtension"));

extension-objects/src/test/java/units/SergeantUnitTest.java

@@ -23,20 +23,18 @@
 
 package units;
 
-import abstractextensions.SergeantExtension;
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertNull;
 
+import org.junit.jupiter.api.Test;
+
 /**
  * Created by Srdjan on 03-May-17.
  */
 public class SergeantUnitTest {
   @Test
   public void getUnitExtension() {
-
+    final var unit = new SergeantUnit("SergeantUnitName");
-    final Unit unit = new SergeantUnit("SergeantUnitName");
 
     assertNull(unit.getUnitExtension("SoldierExtension"));
     assertNotNull(unit.getUnitExtension("SergeantExtension"));

extension-objects/src/test/java/units/SoldierUnitTest.java

@@ -23,26 +23,22 @@
 
 package units;
 
-import abstractextensions.SoldierExtension;
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertNull;
 
+import org.junit.jupiter.api.Test;
+
 /**
  * Created by Srdjan on 03-May-17.
  */
 public class SoldierUnitTest {
   @Test
   public void getUnitExtension() {
-
+    final var unit = new SoldierUnit("SoldierUnitName");
-    final Unit unit = new SoldierUnit("SoldierUnitName");
 
     assertNotNull(unit.getUnitExtension("SoldierExtension"));
     assertNull(unit.getUnitExtension("SergeantExtension"));
     assertNull(unit.getUnitExtension("CommanderExtension"));
-
-
   }
 
 }

extension-objects/src/test/java/units/UnitTest.java

@@ -23,11 +23,11 @@
 
 package units;
 
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNull;
 
+import org.junit.jupiter.api.Test;
+
 /**
  * Created by Srdjan on 03-May-17.
  */
@@ -35,11 +35,11 @@ public class UnitTest {
 
   @Test
   public void testConstGetSet() throws Exception {
-    final String name = "testName";
+    final var name = "testName";
-    final Unit unit = new Unit(name);
+    final var unit = new Unit(name);
     assertEquals(name, unit.getName());
 
-    final String newName = "newName";
+    final var newName = "newName";
     unit.setName(newName);
     assertEquals(newName, unit.getName());