diff --git a/event-driven-architecture/etc/eda.png b/event-driven-architecture/etc/eda.png index 38c433a40..743726451 100644 Binary files a/event-driven-architecture/etc/eda.png and b/event-driven-architecture/etc/eda.png differ diff --git a/event-driven-architecture/etc/eda.ucls b/event-driven-architecture/etc/eda.ucls index 4ddb8b20c..776bedc81 100644 --- a/event-driven-architecture/etc/eda.ucls +++ b/event-driven-architecture/etc/eda.ucls @@ -4,7 +4,7 @@ - + @@ -15,7 +15,7 @@ project="event-driven-architecture" file="/event-driven-architecture/src/main/java/com/iluwatar/eda/handler/UserUpdatedEventHandler.java" binary="false" corner="BOTTOM_RIGHT"> - + @@ -26,17 +26,17 @@ project="event-driven-architecture" file="/event-driven-architecture/src/main/java/com/iluwatar/eda/handler/UserCreatedEventHandler.java" binary="false" corner="BOTTOM_RIGHT"> - + - - + @@ -46,7 +46,7 @@ - + @@ -56,7 +56,7 @@ - + @@ -66,7 +66,7 @@ - + @@ -76,17 +76,17 @@ - + - - + @@ -94,99 +94,87 @@ - + + + + + + + + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + - - - - - - - - - - - - - - - - - - - + + - - + - - - + + + - - + + - - + + - - - - + + + + + + + + + + + + + + + + + + + + + - + + + + + + + + + + + + + + + + + + - - + + diff --git a/event-driven-architecture/src/main/java/com/iluwatar/eda/App.java b/event-driven-architecture/src/main/java/com/iluwatar/eda/App.java index 4179046c8..866b3c9e9 100644 --- a/event-driven-architecture/src/main/java/com/iluwatar/eda/App.java +++ b/event-driven-architecture/src/main/java/com/iluwatar/eda/App.java @@ -22,9 +22,9 @@ */ package com.iluwatar.eda; -import com.iluwatar.eda.event.Event; import com.iluwatar.eda.event.UserCreatedEvent; import com.iluwatar.eda.event.UserUpdatedEvent; +import com.iluwatar.eda.framework.Event; import com.iluwatar.eda.framework.EventDispatcher; import com.iluwatar.eda.handler.UserCreatedEventHandler; import com.iluwatar.eda.handler.UserUpdatedEventHandler; @@ -53,12 +53,12 @@ public class App { public static void main(String[] args) { EventDispatcher dispatcher = new EventDispatcher(); - dispatcher.registerChannel(UserCreatedEvent.class, new UserCreatedEventHandler()); - dispatcher.registerChannel(UserUpdatedEvent.class, new UserUpdatedEventHandler()); + dispatcher.registerHandler(UserCreatedEvent.class, new UserCreatedEventHandler()); + dispatcher.registerHandler(UserUpdatedEvent.class, new UserUpdatedEventHandler()); User user = new User("iluwatar"); - dispatcher.onEvent(new UserCreatedEvent(user)); - dispatcher.onEvent(new UserUpdatedEvent(user)); + dispatcher.dispatch(new UserCreatedEvent(user)); + dispatcher.dispatch(new UserUpdatedEvent(user)); } } diff --git a/event-driven-architecture/src/main/java/com/iluwatar/eda/event/Event.java b/event-driven-architecture/src/main/java/com/iluwatar/eda/event/AbstractEvent.java similarity index 85% rename from event-driven-architecture/src/main/java/com/iluwatar/eda/event/Event.java rename to event-driven-architecture/src/main/java/com/iluwatar/eda/event/AbstractEvent.java index 3ed0f9c9d..54a916c7b 100644 --- a/event-driven-architecture/src/main/java/com/iluwatar/eda/event/Event.java +++ b/event-driven-architecture/src/main/java/com/iluwatar/eda/event/AbstractEvent.java @@ -23,10 +23,10 @@ package com.iluwatar.eda.event; import com.iluwatar.eda.framework.EventDispatcher; -import com.iluwatar.eda.framework.Message; +import com.iluwatar.eda.framework.Event; /** - * The {@link Event} class serves as a base class for defining custom events happening with your + * The {@link AbstractEvent} class serves as a base class for defining custom events happening with your * system. In this example we have two types of events defined. *
    *
  • {@link UserCreatedEvent} - used when a user is created
    • @@ -34,16 +34,16 @@ import com.iluwatar.eda.framework.Message; *
* Events can be distinguished using the {@link #getType() getType} method. */ -public class Event implements Message { +public abstract class AbstractEvent implements Event { /** * Returns the event type as a {@link Class} object * In this example, this method is used by the {@link EventDispatcher} to * dispatch events depending on their type. * - * @return the Event type as a {@link Class}. + * @return the AbstractEvent type as a {@link Class}. */ - public Class getType() { + public Class getType() { return getClass(); } } \ No newline at end of file diff --git a/event-driven-architecture/src/main/java/com/iluwatar/eda/event/UserCreatedEvent.java b/event-driven-architecture/src/main/java/com/iluwatar/eda/event/UserCreatedEvent.java index e3354aaf2..717ed1a9d 100644 --- a/event-driven-architecture/src/main/java/com/iluwatar/eda/event/UserCreatedEvent.java +++ b/event-driven-architecture/src/main/java/com/iluwatar/eda/event/UserCreatedEvent.java @@ -29,7 +29,7 @@ import com.iluwatar.eda.model.User; * This class can be extended to contain details about the user has been created. In this example, * the entire {@link User} object is passed on as data with the event. */ -public class UserCreatedEvent extends Event { +public class UserCreatedEvent extends AbstractEvent { private User user; diff --git a/event-driven-architecture/src/main/java/com/iluwatar/eda/event/UserUpdatedEvent.java b/event-driven-architecture/src/main/java/com/iluwatar/eda/event/UserUpdatedEvent.java index 37ca05932..9646957dc 100644 --- a/event-driven-architecture/src/main/java/com/iluwatar/eda/event/UserUpdatedEvent.java +++ b/event-driven-architecture/src/main/java/com/iluwatar/eda/event/UserUpdatedEvent.java @@ -29,7 +29,7 @@ import com.iluwatar.eda.model.User; * This class can be extended to contain details about the user has been updated. In this example, * the entire {@link User} object is passed on as data with the event. */ -public class UserUpdatedEvent extends Event { +public class UserUpdatedEvent extends AbstractEvent { private User user; diff --git a/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/Message.java b/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/Event.java similarity index 91% rename from event-driven-architecture/src/main/java/com/iluwatar/eda/framework/Message.java rename to event-driven-architecture/src/main/java/com/iluwatar/eda/framework/Event.java index ee9c48965..c63d2746f 100644 --- a/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/Message.java +++ b/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/Event.java @@ -23,15 +23,15 @@ package com.iluwatar.eda.framework; /** - * A {@link Message} is an object with a specific type that is associated + * A {@link Event} is an object with a specific type that is associated * to a specific {@link Handler}. */ -public interface Message { +public interface Event { /** * Returns the message type as a {@link Class} object. In this example the message type is * used to handle events by their type. * @return the message type as a {@link Class}. */ - Class getType(); + Class getType(); } diff --git a/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/EventDispatcher.java b/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/EventDispatcher.java index 69e2cf0e3..9f8e29315 100644 --- a/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/EventDispatcher.java +++ b/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/EventDispatcher.java @@ -22,19 +22,16 @@ */ package com.iluwatar.eda.framework; -import com.iluwatar.eda.event.Event; - import java.util.HashMap; import java.util.Map; /** * Handles the routing of {@link Event} messages to associated handlers. * A {@link HashMap} is used to store the association between events and their respective handlers. - * */ public class EventDispatcher { - private Map, Handler> handlers; + private Map, Handler> handlers; public EventDispatcher() { handlers = new HashMap<>(); @@ -46,8 +43,8 @@ public class EventDispatcher { * @param eventType The {@link Event} to be registered * @param handler The {@link Handler} that will be handling the {@link Event} */ - public void registerChannel(Class eventType, - Handler handler) { + public void registerHandler(Class eventType, + Handler handler) { handlers.put(eventType, handler); } @@ -56,8 +53,12 @@ public class EventDispatcher { * * @param event The {@link Event} to be dispatched */ - public void onEvent(Event event) { - handlers.get(event.getClass()).onEvent(event); + @SuppressWarnings("unchecked") + public void dispatch(E event) { + Handler handler = (Handler) handlers.get(event.getClass()); + if (handler != null) { + handler.onEvent(event); + } } } \ No newline at end of file diff --git a/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/Handler.java b/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/Handler.java index 9c800a4d4..44bdab6dc 100644 --- a/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/Handler.java +++ b/event-driven-architecture/src/main/java/com/iluwatar/eda/framework/Handler.java @@ -22,13 +22,11 @@ */ package com.iluwatar.eda.framework; -import com.iluwatar.eda.event.Event; - /** * This interface can be implemented to handle different types of messages. * Every handler is responsible for a single of type message */ -public interface Handler { +public interface Handler { /** * The onEvent method should implement and handle behavior related to the event. @@ -36,5 +34,5 @@ public interface Handler { * a queue to be consumed by other sub systems. * @param event the {@link Event} object to be handled. */ - void onEvent(Event event); + void onEvent(E event); } \ No newline at end of file diff --git a/event-driven-architecture/src/main/java/com/iluwatar/eda/handler/UserCreatedEventHandler.java b/event-driven-architecture/src/main/java/com/iluwatar/eda/handler/UserCreatedEventHandler.java index c51b3391a..3ef4e8255 100644 --- a/event-driven-architecture/src/main/java/com/iluwatar/eda/handler/UserCreatedEventHandler.java +++ b/event-driven-architecture/src/main/java/com/iluwatar/eda/handler/UserCreatedEventHandler.java @@ -22,7 +22,6 @@ */ package com.iluwatar.eda.handler; -import com.iluwatar.eda.event.Event; import com.iluwatar.eda.event.UserCreatedEvent; import com.iluwatar.eda.framework.Handler; @@ -32,9 +31,10 @@ import com.iluwatar.eda.framework.Handler; public class UserCreatedEventHandler implements Handler { @Override - public void onEvent(Event message) { + public void onEvent(UserCreatedEvent event) { - UserCreatedEvent userCreatedEvent = (UserCreatedEvent) message; - System.out.printf("User with %s has been Created!", userCreatedEvent.getUser().getUsername()); + System.out.println(String.format( + "User '%s' has been Created!", event.getUser().getUsername())); } + } diff --git a/event-driven-architecture/src/main/java/com/iluwatar/eda/handler/UserUpdatedEventHandler.java b/event-driven-architecture/src/main/java/com/iluwatar/eda/handler/UserUpdatedEventHandler.java index 5be4ab5cc..0311d5781 100644 --- a/event-driven-architecture/src/main/java/com/iluwatar/eda/handler/UserUpdatedEventHandler.java +++ b/event-driven-architecture/src/main/java/com/iluwatar/eda/handler/UserUpdatedEventHandler.java @@ -22,7 +22,6 @@ */ package com.iluwatar.eda.handler; -import com.iluwatar.eda.event.Event; import com.iluwatar.eda.event.UserUpdatedEvent; import com.iluwatar.eda.framework.Handler; @@ -32,9 +31,9 @@ import com.iluwatar.eda.framework.Handler; public class UserUpdatedEventHandler implements Handler { @Override - public void onEvent(Event message) { + public void onEvent(UserUpdatedEvent event) { - UserUpdatedEvent userUpdatedEvent = (UserUpdatedEvent) message; - System.out.printf("User with %s has been Updated!", userUpdatedEvent.getUser().getUsername()); + System.out.println(String.format( + "User '%s' has been Updated!", event.getUser().getUsername())); } } diff --git a/event-driven-architecture/src/test/java/com/iluwatar/eda/event/UserCreatedEventTest.java b/event-driven-architecture/src/test/java/com/iluwatar/eda/event/UserCreatedEventTest.java index 754fac678..b9074faf2 100644 --- a/event-driven-architecture/src/test/java/com/iluwatar/eda/event/UserCreatedEventTest.java +++ b/event-driven-architecture/src/test/java/com/iluwatar/eda/event/UserCreatedEventTest.java @@ -29,13 +29,13 @@ import org.junit.Test; import static org.junit.Assert.assertEquals; /** - * {@link UserCreatedEventTest} tests and verifies {@link Event} behaviour. + * {@link UserCreatedEventTest} tests and verifies {@link AbstractEvent} behaviour. */ public class UserCreatedEventTest { /** - * This unit test should correctly return the {@link Event} class type when calling the - * {@link Event#getType() getType} method. + * This unit test should correctly return the {@link AbstractEvent} class type when calling the + * {@link AbstractEvent#getType() getType} method. */ @Test public void testGetEventType() { diff --git a/event-driven-architecture/src/test/java/com/iluwatar/eda/framework/EventDispatcherTest.java b/event-driven-architecture/src/test/java/com/iluwatar/eda/framework/EventDispatcherTest.java index 8db315ff4..21956afec 100644 --- a/event-driven-architecture/src/test/java/com/iluwatar/eda/framework/EventDispatcherTest.java +++ b/event-driven-architecture/src/test/java/com/iluwatar/eda/framework/EventDispatcherTest.java @@ -22,7 +22,6 @@ */ package com.iluwatar.eda.framework; -import com.iluwatar.eda.framework.EventDispatcher; import com.iluwatar.eda.event.UserCreatedEvent; import com.iluwatar.eda.event.UserUpdatedEvent; import com.iluwatar.eda.handler.UserCreatedEventHandler; @@ -49,8 +48,8 @@ public class EventDispatcherTest { EventDispatcher dispatcher = spy(new EventDispatcher()); UserCreatedEventHandler userCreatedEventHandler = spy(new UserCreatedEventHandler()); UserUpdatedEventHandler userUpdatedEventHandler = spy(new UserUpdatedEventHandler()); - dispatcher.registerChannel(UserCreatedEvent.class, userCreatedEventHandler); - dispatcher.registerChannel(UserUpdatedEvent.class, userUpdatedEventHandler); + dispatcher.registerHandler(UserCreatedEvent.class, userCreatedEventHandler); + dispatcher.registerHandler(UserUpdatedEvent.class, userUpdatedEventHandler); User user = new User("iluwatar"); @@ -58,15 +57,14 @@ public class EventDispatcherTest { UserUpdatedEvent userUpdatedEvent = new UserUpdatedEvent(user); //fire a userCreatedEvent and verify that userCreatedEventHandler has been invoked. - dispatcher.onEvent(userCreatedEvent); + dispatcher.dispatch(userCreatedEvent); verify(userCreatedEventHandler).onEvent(userCreatedEvent); - verify(dispatcher).onEvent(userCreatedEvent); + verify(dispatcher).dispatch(userCreatedEvent); //fire a userCreatedEvent and verify that userUpdatedEventHandler has been invoked. - dispatcher.onEvent(userUpdatedEvent); + dispatcher.dispatch(userUpdatedEvent); verify(userUpdatedEventHandler).onEvent(userUpdatedEvent); - verify(dispatcher).onEvent(userUpdatedEvent); + verify(dispatcher).dispatch(userUpdatedEvent); } - }