Many-to-one and JoinFormula

Author: AnghelLeonard

HibernateSpringBootJoinFormula/src/main/java/com/bookstore/entity/Book.java

@@ -32,7 +32,7 @@ public class Book implements Serializable {
             + "WHERE b.price < price AND b.author_id = author_id "
             + "ORDER BY b.price DESC "
             + "LIMIT 1)")
-    private Book prevBook;
+    private Book nextBook;
 
     public Long getId() {
         return id;
@@ -74,13 +74,13 @@ public void setPrice(int price) {
         this.price = price;
     }
 
-    public Book getPrevBook() {
-        return prevBook;
+    public Book getNextBook() {
+        return nextBook;
     }
 
-    public void setPrevBook(Book prevBook) {
-        this.prevBook = prevBook;
-    }   
+    public void setNextBook(Book nextBook) {
+        this.nextBook = nextBook;
+    }    
 
     @Override
     public String toString() {

HibernateSpringBootJoinFormula/src/main/java/com/bookstore/repository/BookRepository.java

@@ -3,11 +3,7 @@
 import com.bookstore.entity.Book;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.stereotype.Repository;
-import org.springframework.transaction.annotation.Transactional;
 
 @Repository
-public interface BookRepository extends JpaRepository<Book, Long> {
-
-    @Transactional(readOnly = true)
-    Book findByTitle(String title);
+public interface BookRepository extends JpaRepository<Book, Long> {   
 }

HibernateSpringBootJoinFormula/src/main/java/com/bookstore/service/BookstoreService.java

@@ -18,10 +18,10 @@ public BookstoreService(BookRepository bookRepository) {
     @Transactional(readOnly = true)
     public void fetchBooks() {
 
-        Book book = bookRepository.findById(4L).orElseThrow();
-        Book prevBook = book.getPrevBook();
+        Book book = bookRepository.findById(7L).orElseThrow();
+        Book nextBook = book.getNextBook();
 
-        System.out.println("Fetched book with id 4: " + book);
-        System.out.println("Fetched book with next smallest price: " + prevBook);
+        System.out.println("Fetched book with id 7: " + book);
+        System.out.println("Fetched book with next smallest price: " + nextBook);
     }
 }