package au.com.spatiumxl.model;

public class Book {

    public enum Status { READ, UNREAD }

    private String title; 
    private Book.Status status;  

    public Book(String title) {  
        this.title = title; 
        this.status = Book.Status.UNREAD; 
    }

    public String getTitle() {  
        return title; 
    }

    public Book.Status getStatus() { 
        return status; 
    }
}

package au.com.spatiumxl.ejb;

[...]

import au.com.spatiumxl.model.Book;

@Stateless
@LocalBean
public class BookService {

    public List<Book> getBooks() {  
        List<Book> books = new ArrayList<>();
        books.add(new Book("title1"));  
        return books; 
    }
}

package au.com.spatiumxl.rest;

[...]

import au.com.spatiumxl.ejb.BookService;
import au.com.spatiumxl.model.Book;

@RequestScoped
@Path("")public 
class BookEndPoint {  

    @Inject BookService bookService;  

    @GET @Path("/get-books") 
    @Produces("application/json") 
    public List<Book> getBooks() {  
        return bookService.getBooks(); 
    }
}

java.lang.Thread
 org.jboss.modules.ModuleClassLoader
  org.jboss.modules.Module
   org.jboss.modules.LocalModuleLoader
    java.util.concurrent.ConcurrentHashMap
     java.util.concurrent.ConcurrentHashMap$Node[]
      java.util.concurrent.ConcurrentHashMap$Node
       org.jboss.modules.ModuleLoader$FutureModule
        org.jboss.modules.Module
         org.jboss.modules.ModuleClassLoader
          java.util.Vector
           java.lang.Object[]
            org.jboss.resteasy.plugins.providers.jsonb.AbstractJsonBindingProvider
             org.eclipse.yasson.internal.JsonBinding
              org.eclipse.yasson.internal.JsonbContext
               org.eclipse.yasson.internal.MappingContext
                java.util.concurrent.ConcurrentHashMap
                 java.util.concurrent.ConcurrentHashMap$Node[]
                  java.util.concurrent.ConcurrentHashMap$Node
                   org.eclipse.yasson.internal.model.ClassModel
                    org.eclipse.yasson.internal.model.PropertyModel[]
                     org.eclipse.yasson.internal.model.PropertyModel
                      au.com.spatiumxl.model.Book$Status