Bael 1674 (#4335)

* Handle events - BAEL - 1674

* BAEL -1674 - test

* test - BAEL-1674

* Change system.out to logger

* minor change

spring-data-rest/src/test/java/com/baeldung/events/AuthorEventHandlerTest.java

@@ -0,0 +1,29 @@
+package com.baeldung.events;
+
+import com.baeldung.models.Author;
+import org.junit.Test;
+import org.mockito.Mockito;
+import org.springframework.data.rest.core.annotation.RepositoryEventHandler;
+
+import static org.mockito.Mockito.mock;
+
+public class AuthorEventHandlerTest {
+
+        @Test
+        public void whenCreateAuthorThenSuccess() {
+                Author author = mock(Author.class);
+                AuthorEventHandler authorEventHandler = new AuthorEventHandler();
+                authorEventHandler.handleAuthorBeforeCreate(author);
+                Mockito.verify(author,Mockito.times(1)).getName();
+
+        }
+
+        @Test
+        public void whenDeleteAuthorThenSuccess() {
+                Author author = mock(Author.class);
+                AuthorEventHandler authorEventHandler = new AuthorEventHandler();
+                authorEventHandler.handleAuthorAfterDelete(author);
+                Mockito.verify(author,Mockito.times(1)).getName();
+
+        }
+}

spring-data-rest/src/test/java/com/baeldung/events/BookEventHandlerTest.java

@@ -0,0 +1,28 @@
+package com.baeldung.events;
+
+import com.baeldung.models.Author;
+import com.baeldung.models.Book;
+import org.junit.Test;
+import org.mockito.Mockito;
+
+import static org.mockito.Mockito.mock;
+
+public class BookEventHandlerTest {
+        @Test
+        public void whenCreateBookThenSuccess() {
+                Book book = mock(Book.class);
+                BookEventHandler bookEventHandler = new BookEventHandler();
+                bookEventHandler.handleBookBeforeCreate(book);
+                Mockito.verify(book,Mockito.times(1)).getAuthors();
+
+        }
+
+        @Test
+        public void whenCreateAuthorThenSuccess() {
+                Author author = mock(Author.class);
+                BookEventHandler bookEventHandler = new BookEventHandler();
+                bookEventHandler.handleAuthorBeforeCreate(author);
+                Mockito.verify(author,Mockito.times(1)).getBooks();
+
+        }
+}