HibernateException: Could not obtain transaction-synchronized Session for current thread

Question

I am getting error:

Exception in thread \"main\" org.hibernate.HibernateException: 
Could not obtain transaction-synchronized Session for current thread


        

Answer 1

I had same error as "org.hibernate.HibernateException: Could not obtain transaction-synchronized Session for current thread"

I just used @Transactional(readOnly = false) in my Dao implementation resolved my issue

Answer 2

The error org.hibernate.MappingException: Unknown entity: ProductPart indicates there is no entity with name ProductPart. One way to fix this issue is to pass the Class object to createCriteria method as:

createCriteria(ProductPart.class)

From API the difference in using String and Class is as follows:

Session.createCriteria(String)

Create a new Criteria instance, for the given entity name. 

Session.createCriteria(Class)

Create a new Criteria instance, for the given entity class, or a superclass of an entity class, with the given alias.

If you pass a String then hibernate looks for an entity whose name is declared as ProductPart.

Answer 3

With Hibernate 4.x and Spring 4.x, just Add @Transactional after @Repository it will solve this synchronizaion exception.

Answer 4

You must enable the transaction support (<tx:annotation-driven> or @EnableTransactionManagement ) and declare the transactionManager and it should work through the SessionFactory.

You must add @Transactional into your @Repository

With @Transactional in your @Repository Spring is able to apply transactional support into your repository.

Your Student class has no the @javax.persistence.* annotations how @Entity, I am assuming the Mapping Configuration for that class has been defined through XML.

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