The code has been reformatted using the intelliJ-formatter.xml from https://github.com/eugenp/tutorials/blob/master/intelliJ/intelliJ-formatter.xml

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/actions/BookReadActions.java

@@ -3,7 +3,8 @@ package com.baeldung.hexarch.boostrore.actions;
 import lombok.Getter;
 import lombok.Setter;
 
-@Getter @Setter
+@Getter
+@Setter
 public class BookReadActions {
     private String bookId;
     private String bookName;

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/controller/AuthorsController.java

@@ -13,8 +13,7 @@ import org.springframework.web.bind.annotation.RestController;
 public class AuthorsController {
     private final AuthorsRepository authorsRepository;
 
-    @PutMapping(value = "/api/v1/authors",
+    @PutMapping(value = "/api/v1/authors", consumes = MediaType.APPLICATION_JSON_VALUE)
-            consumes = MediaType.APPLICATION_JSON_VALUE)
     private void createAuthor(@RequestBody final Author author) {
         com.baeldung.hexarch.boostrore.model.Author author1 = new com.baeldung.hexarch.boostrore.model.Author();
         author1.setLastName(author.getLastName());

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/controller/BookController.java

@@ -20,21 +20,14 @@ import java.util.stream.Collectors;
 public class BookController {
     private final BookOperations bookOperations;
 
-    @PutMapping(value = "/api/v1/books",
+    @PutMapping(value = "/api/v1/books", consumes = MediaType.APPLICATION_JSON_VALUE)
-            consumes = MediaType.APPLICATION_JSON_VALUE)
     @ResponseBody
-    private BookResponse createBook(
+    private BookResponse createBook(@RequestBody final CreateBookRequest createBookRequest) {
-            @RequestBody final CreateBookRequest createBookRequest) {
+        Set<String> authorEmailSet = createBookRequest.getAuthors().stream().map(Author::getEmailId).collect(Collectors.toSet());
-        Set<String> authorEmailSet = createBookRequest.getAuthors()
-                .stream().map(Author::getEmailId)
-                .collect(Collectors.toSet());
 
-        Book book = bookOperations.create(createBookRequest.getIsbn(),
+        Book book = bookOperations.create(createBookRequest.getIsbn(), createBookRequest.getTitle(), authorEmailSet);
-                createBookRequest.getTitle(), authorEmailSet);
 
         //        book.getAuthors().stream().map()
-        return BookResponse.builder()
+        return BookResponse.builder().isbn(book.getIsbn()).title(book.getName()).build();
-                .isbn(book.getIsbn()).title(book.getName())
-                .build();
     }
 }

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/controller/dto/Author.java

@@ -1,9 +1,8 @@
 package com.baeldung.hexarch.boostrore.controller.dto;
 
-import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import lombok.Builder;
-import com.fasterxml.jackson.databind.annotation.JsonPOJOBuilder;
+import lombok.EqualsAndHashCode;
-import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import lombok.Value;
-import lombok.*;
 
 @Value
 @Builder

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/domain/AuthorsOperation.java

@@ -4,8 +4,12 @@ import com.baeldung.hexarch.boostrore.model.Author;
 
 public interface AuthorsOperation {
     Author create(String firstName, String lastName, String emailId);
+
     Author getAuthorByEmailId(final String emailId);
+
     Author get(final long id);
+
     void delete(final String emailId);
+
     void delete(final long id);
 }

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/domain/AuthorsOperationsImpl.java

@@ -9,6 +9,7 @@ import org.springframework.stereotype.Service;
 @AllArgsConstructor
 public class AuthorsOperationsImpl implements AuthorsOperation {
     private final AuthorsRepository authorsRepository;
+
     @Override
     public Author create(String firstName, String lastName, String emailId) {
         Author author = new Author();

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/domain/BookOperations.java

@@ -5,11 +5,12 @@ import com.baeldung.hexarch.boostrore.model.Book;
 
 import java.util.Set;
 
-
 public interface BookOperations {
-    Book create(final String isbn, final String bookName,
+    Book create(final String isbn, final String bookName, Set<String> authorEmails);
-                Set<String> authorEmails);
+
     Book getBookById(final long id);
+
     Book getBookByIsbn(final String isbn);
+
     Set<Author> getAuthorsOfBook(final long id);
 }

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/domain/BookOperationsImpl.java

@@ -22,13 +22,10 @@ public class BookOperationsImpl implements BookOperations {
         // if the book with given isbn already exists then let us
         // throw an error
         if (booksRepository.findByIsbn(isbn).isPresent()) {
-            throw new RuntimeException("A Book with ISBN " + isbn
+            throw new RuntimeException("A Book with ISBN " + isbn + " already exists");
-                    + " already exists");
         }
         //Ask for the Author objects
-        Set<Author> authorSet = authors.stream()
+        Set<Author> authorSet = authors.stream().map(this::upsetAuthor).collect(Collectors.toSet());
-                .map(this::upsetAuthor)
-                .collect(Collectors.toSet());
 
         // create the book object and associate the authors
         Book book = new Book();
@@ -62,8 +59,7 @@ public class BookOperationsImpl implements BookOperations {
         // Check if a author already exists with given email id. if not create the Author
         // else return the author we found
         if (byEmailId.isEmpty()) {
-            throw new RuntimeException("Author not found: email id "
+            throw new RuntimeException("Author not found: email id " + email);
-                    + email);
         }
         return byEmailId.get();
     }

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/model/Author.java

@@ -9,11 +9,13 @@ import javax.persistence.Id;
 import javax.persistence.Table;
 import java.util.Objects;
 
-@Getter @Setter
+@Getter
+@Setter
 @Entity(name = "authors")
 @Table(name = "authors")
 public class Author {
-    @Id @GeneratedValue
+    @Id
+    @GeneratedValue
     private long id;
     private String firstName;
     private String lastName;
@@ -21,8 +23,10 @@ public class Author {
 
     @Override
     public boolean equals(Object o) {
-        if (this == o) return true;
+        if (this == o)
-        if (o == null || getClass() != o.getClass()) return false;
+            return true;
+        if (o == null || getClass() != o.getClass())
+            return false;
         Author author = (Author) o;
         return id == author.id;
     }

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/model/Book.java

@@ -3,12 +3,18 @@ package com.baeldung.hexarch.boostrore.model;
 import lombok.Getter;
 import lombok.Setter;
 
-import javax.persistence.*;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
 import java.util.Objects;
 import java.util.Set;
 
-@Getter @Setter
+@Getter
-@Entity(name = "books")  @Table(name = "books")
+@Setter
+@Entity(name = "books")
+@Table(name = "books")
 public class Book {
     @Id
     @GeneratedValue
@@ -20,8 +26,10 @@ public class Book {
 
     @Override
     public boolean equals(Object o) {
-        if (this == o) return true;
+        if (this == o)
-        if (o == null || getClass() != o.getClass()) return false;
+            return true;
+        if (o == null || getClass() != o.getClass())
+            return false;
         Book book = (Book) o;
         return id == book.id;
     }

book-store-using-hexagonal-architecture/src/main/java/com/baeldung/hexarch/boostrore/repository/AuthorsRepository.java

@@ -9,5 +9,6 @@ import java.util.Optional;
 @Repository
 public interface AuthorsRepository extends JpaRepository<Author, Long> {
     Optional<Author> findByEmailId(final String emailId);
+
     void deleteByEmailId(final String emailId);
 }