hibernate: LazyInitializationException: could not initialize proxy

user_17304 0
Viewed 207761

Here's one that has me perplexed. I'm trying to implement a basic Hibernate DAO structure, but am having a problem.

Here's the essential code:

int startingCount = sfdao.count();
sfdao.create( sf );
SecurityFiling sf2 = sfdao.read( sf.getId() );
sfdao.delete( sf );
int endingCount = sfdao.count();

assertTrue( startingCount == endingCount );
assertTrue( sf.getId().longValue() == sf2.getId().longValue() );
assertTrue( sf.getSfSubmissionType().equals( sf2.getSfSubmissionType() ) );
assertTrue( sf.getSfTransactionNumber().equals( sf2.getSfTransactionNumber() ) );

It fails on the third assertTrue where it's trying to compare a value in sf to the corresponding value in sf2. Here's the exception:

org.hibernate.LazyInitializationException: could not initialize proxy - no Session
    at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:86)
    at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:140)
    at org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:190)
    at com.freightgate.domain.SecurityFiling_$$_javassist_7.getSfSubmissionType(SecurityFiling_$$_javassist_7.java)
    at com.freightgate.dao.SecurityFilingTest.test(SecurityFilingTest.java:73)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:40)
lazy-evaluation initialization hibernate
14 Answers

This generally means that the owning Hibernate session has already closed. You can do one of the following to fix it:

  1. whichever object creating this problem, use HibernateTemplate.initialize(object name)
  2. Use lazy=false in your hbm files.
digitalsanctum_224360

See my article. I had the same problem - LazyInitializationException - and here's the answer I finally came up with:
http://community.jboss.org/wiki/LazyInitializationExceptionovercome
Setting lazy=false is not the answer - it can load everything all at once, and that's not necessarily good. Example:
1 record table A references:
5 records table B references:
25 records table C references:
125 records table D
...
etc. This is but one example of what can go wrong.
--Tim Sabin

user_6202950

Okay, finally figured out where I was remiss. I was under the mistaken notion that I should wrap each DAO method in a transaction. Terribly wrong! I've learned my lesson. I've hauled all the transaction code from all the DAO methods and have set up transactions strictly at the application/manager layer. This has totally solved all my problems. Data is properly lazy loaded as I need it, wrapped up and closed down once I do the commit.

Life is goodly... :)

user_173040
brd6644_417540
Related