JAVA

@embeddedid

@Entity
public class Book {

    @EmbeddedId
    private BookId id;
    private String genre;
    private Integer price;

    //standard getters and setters
}

@embeddedid

@Embeddable
public class BookId implements Serializable {

    private String author;
    private String name;

    // standard getters and setters
}