And, most importantly, both primitive longs and java.lang.Longs are immutable—effectively passed by value—unlike java.util.Dates; I'd be really pissed off to find something like foo.getLastUpdate().setTime(System.currentTimeMillis()) when debugging somebody else's code.

2013年11月12日 · Use the Hibernate.initialize for the remaining collections. So, in your case, you need a first JPQL query like this one: MyEntity entity = session.createQuery("select e from MyEntity e join fetch e.addreses where e.id = :id", MyEntity.class) .setParameter("id", entityId) .getSingleResult(); Hibernate.initialize(entity.persons);

I'm trying to do a basic "OR" on three fields using a hibernate criteria query. Example class Whatever{ string name; string address; string phoneNumber; } I'd like to build a criteria query w...

2010年5月29日 · A static inner class is conceptually no different than a regular general class declared in a .java file. Since Hibernate needs to instantiate ProjectPK independantly of the Project instance, ProjectPK either needs to be a static inner class, or declared in it's own .java file. reference org.hibernate.InstantiationException: No default constructor

2014年8月16日 · Simply, @Temporal is a Hibernate JPA annotation which should only be set on a java.util.Date or java.util.Calendar. It helps to convert the date and time values from Java object to compatible database type and will retrieve it back to the application.

2015年12月8日 · This has the advantage, that the schema auto-generates the value even if it is used without hibernate. This might make your code db-specific though: import javax.persistence.Column; @Column(columnDefinition = "serial") // PostgreSQL @Column(columnDefinition = "integer auto_increment") // MySql

hibernate.dialect: The class name of a Hibernate org.hibernate.dialect.Dialect which allows Hibernate to generate SQL optimized for a particular relational database. To change the database, you must: Provide an appropriate JDBC driver for the database on the class path,

2010年4月4日 · Now, if we close the Hibernate Session, the persistent instance will become a detached instance: it isn't attached to a Session anymore (but can still be modified and reattached to a new Session later though). All this is clearly explained in the whole Chapter 10. Working with objects of the Hibernate documentation that I'm only paraphrasing ...

2012年12月19日 · There is no point using HQL to do that, you can use direct SQL if you want to do that, through a JDBC query (or even through a Hibernate query, you can use SQL queries). Using HQL queries to update is only recommended when doing batch updates, not a single row.

Hibernate can be fast. Designing a good schema, tuning your queries, and getting good performance is kind of an artform. Remember, under the covers its all sql anyway, so anything you can do with sql you can do with hibernate. Typically on advanced application the hibernate mapping/schema is only the initial step of writing your persistence layer.