Hibernate 5 :- org.hibernate.MappingException: Unknown entity

by

I have fixed the same issue with Hibernate 5. There is a problem in this code

Configuration configuration = new Configuration();
configuration.configure();

ServiceRegistry sr = new StandardServiceRegistryBuilder().applySettings(
    configuration.getProperties()).build();

SessionFactory sf = configuration.buildSessionFactory(sr);

This code works fine for Hibernate 4.3.5, but the same code has the same issue for Hibernate 5.

When you do configuration.buildSessionFactory(sr), using Hibernate 5, Configuration losts all information about mapping that gets by call configuration.configure().

Solution

To fix the issue, if you use standard configuration files hibernate.cfg.xml and hibernate.properties, you can create the session factory by this way (without ServiceRegistry) 

SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();

Loading properties

If you have properties in a file other then hibernate.properties, you can build session factory using StandardServiceRegistryBuilder (anyway, if you have hibernate.properties and other file, it will be loaded both)

To load properties as a resource

ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().
    configure().loadProperties("hibernate-h2.properties").build();
SessionFactory sf = new Configuration().buildSessionFactory(serviceRegistry);

You need to have hibernate-h2.properties in the class path (root of the sources folder, resources folder). You can specify a path from the root source folder too
/com/github/xxx/model/hibernate-h2.properties.

To load properties from a path in the file system

File propertiesPath = new File("some_path");
ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().
    configure().loadProperties(propertiesPath).build();
SessionFactory sf = new Configuration().buildSessionFactory(serviceRegistry);

You can find an example console application using this approach here fluent-hibernate-mysql. It uses a utility class to build the session factory from the fluent-hibernate library.

Incorrect Hibernate 5 tutorial

There is an incorrect example in Hibernate 5 tutorial 1.1.6. Startup and helpers. It uses this code

 return new Configuration().configure().buildSessionFactory(
                new StandardServiceRegistryBuilder().build() );

It doesn’t do a proper configuration.

More Related Contents:

  1. Using Hibernate’s ScrollableResults to slowly read 90 million records
  2. The server time zone value ‘AEST’ is unrecognized or represents more than one time zone
  3. Unable to get spring boot to automatically create database schema
  4. Hibernate: Automatically creating/updating the db tables based on entity classes
  5. No Dialect mapping for JDBC type: 1111
  6. ImprovedNamingStrategy no longer working in Hibernate 5
  7. @GeneratedValue polymorphic abstract superclass over MySQL
  8. Spring boot JPA insert in TABLE with uppercase name with Hibernate
  9. Can Hibernate work with MySQL’s “ON DUPLICATE KEY UPDATE” syntax?
  10. Spring, Hibernate, Blob lazy loading
  11. How can I use MySQL assign operator(:=) in hibernate native query?
  12. Enum in Hibernate, persisting as an enum
  13. When are connections returned to the connection pool with Spring JPA (Hibernate) Entity Manager?
  14. Hibernate Criteria Query to get specific columns
  15. com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed
  16. SQL Error: 0, SQLState: 08S01 Communications link failure [duplicate]
  17. Invalid syntax error “type= MyISAM” in DDL generated by Hibernate
  18. Hibernate: Create Mysql InnoDB tables instead of MyISAM
  19. No matter what, I can’t batch MySQL INSERT statements in Hibernate
  20. com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source
  21. org.hibernate.InstantiationException: No default constructor for entity: : principal.Cliente
  22. Is there a more efficient way of making pagination in Hibernate than executing select and count queries?
  23. How to setup Hibernate to read/write to different datasources?
  24. Hibernate Criteria API: get n random rows
  25. Unable to get multiple Table entities through Stored procedure using hibernate
  26. Make hibernate backquote all table / column names
  27. Creation timestamp and last update timestamp with Hibernate and MySQL
  28. Hibernate : How override an attribute from mapped super class
  29. @OneToMany and composite primary keys?
  30. mapping Hibernate query results to custom class?

Leave a Comment