Now Libreplan can be run on Java8.
This implied some changes:
* Latest versions of hibernate use the Bean Validation API. This
implied renaming the imports and use ConstraintViolationException
instead of InvalidValue. Besides some constraints had to be renamed,
otherwise they wouldn't be recognized by Hibernate validation. In
the new version of Hibernate validator @AssertTrue can only be
applied to properties. So all methods it was applied to must follow
the is.* format.
Automatic execution of Bean Validation API is disabled, otherwise an
infinite loop would happen. This is because there are some
validation constraints that do launch queries to the database. This
causes a flush of the objects in the session and automatic
validation is called again.
* A new library for persisting JodaTime is necessary since
joda-time-hibernate is incompatible with hibernate 4. This library
can automatically register its types for Date conversion so they're
removed from configuration.
* Now, in some places, an InvalidDataAccessApiUsageException is thrown
instead of a DataIntegrityViolationException.
This is because no constraint is violated, the API is being used
incorrectly because a transient instance is being provided where a
persisted one was expected.
* In hibernate 4 listeners cannot be configured via properties.
HibernateDatabaseModificationsListener registers itself in its @PostConstruct method.
* ehcache classes used are now different.
