org.hibernate.AssertionFailure: null id in entry (don't flush the Session after an exception occurs)

Question

I have a hibernate and JSF2 application going to the deployment server and suddenly throwing an org.hibernate.AssertionFailure: null id in exception. I will provide the stack trace and code immediately but here are four important issues first:

1. This happens only on the deployment server (Jboss & MySql running on Windows Sever 2008.) It does not happen on my development machine (Tomcat and MySql running on Windoes 7 Pro) and also not on the staging environment (Jboss and MySql running on Linux.)

2. Researching this, it seems that people get this error when trying to insert an object. But I get the error when I'm doing a simple query. (various different queries, actually, as the error pops up on several pages randomly.)

3. The error hits only every now and then. If I do a Jboss restart it goes away, but a time later returns. Also, it's not consistent, on some clicks it's there, on others it's not. Even when it hits, when I do a simple refresh of the page it returns fine.

4. I'm using c3p0 (config below)

Any idea what's going on?

The code details:

This happens on an address object. Here's the full hbm:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="com.idex.auctions.model">
<class name="Address" table="address" lazy="true">
  <id name="addressID" column="AddressID">
        <generator class="native"/>            
  </id>

  <property name="street" column="street"/> 
  <property name="city" column="city"/> 
  <property name="zip" column="zip"/> 
  <property name="state" column="state"/> 
  <property name="region" column="region"/> 
  <property name="country" column="country"/> 

  <many-to-one name="user" 
       class="com.idex.auctions.model.User" 
       column="userid" 
       unique="true" 
       cascade="save-update"/>
 </class> 
</hibernate-mapping>

The Java class is straight forward:

public class Address implements Serializable {
private static final long serialVersionUID = 7485582614444496906L;

private long addressID;
private String street;
private String city;
private String zip;
private String state;
private String region;
private String country;
private User user;

public Address() {

}
public long getAddressID() {
    return addressID;
}
public void setAddressID(long addressID) {
    this.addressID = addressID;
}
public String getStreet() {
    return street;
}
public void setStreet(String street) {
    this.street = street;
}
public String getCity() {
    return city;
}
public void setCity(String city) {
    this.city = city;
}
public String getZip() {
    return zip;
}
public void setZip(String zip) {
    this.zip = zip;
}
public String getState() {
    return state;
}
public void setState(String state) {
    this.state = state;
}
public String getRegion() {
    return region;
}
public void setRegion(String region) {
    this.region = region;
}
public String getCountry() {
    return country;
}
public void setCountry(String country) {
    this.country = country;
}
public User getUser() {
    return user;
}
public void setUser(User user) {
    this.user = user;
}

}

The c3p0 configuration:

<property name="hibernate.c3p0.acquire_increment">1</property> 
<property name="hibernate.c3p0.idle_test_period">1000</property> 
<property name="hibernate.c3p0.max_size">20</property>  
<property name="hibernate.c3p0.min_size">5</property>
<property name="hibernate.c3p0.timeout">1800</property>
<property name="hibernate.c3p0.max_statements">0</property>
<property name="connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>

The versions used are

hibernate3.jar

c3p0-0.9.1.2.jar

myfaces-api-2.1.4.jar

myfaces-impl-2.1.4.jar

mysql-connector-java-5.1.20-bin.jar

The full stacktrace

org.hibernate.AssertionFailure: null id in com.idex.auctions.model.Address entry 
    (don't flush the Session after an exception occurs)
org.hibernate.event.def.DefaultFlushEntityEventListener.checkId(
                                          DefaultFlushEntityEventListener.java:78)
org.hibernate.event.def.DefaultFlushEntityEventListener.getValues(
                                          DefaultFlushEntityEventListener.java:187)
org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(
                                          DefaultFlushEntityEventListener.java:143)
org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(
                                          AbstractFlushingEventListener.java:219)
org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(
                                          AbstractFlushingEventListener.java:99)
org.hibernate.event.def.DefaultAutoFlushEventListener.onAutoFlush(
                                          DefaultAutoFlushEventListener.java:58)
org.hibernate.impl.SessionImpl.autoFlushIfRequired(SessionImpl.java:997)
org.hibernate.impl.SessionImpl.list(SessionImpl.java:1142)
org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
com.idex.auctions.manager.DatabaseManager.getAllObjects(DatabaseManager.java:464)
com.idex.auctions.ui.NavBean.gotoHome(NavBean.java:40)
sun.reflect.GeneratedMethodAccessor350.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
javax.el.BeanELResolver.invokeMethod(BeanELResolver.java:735)
javax.el.BeanELResolver.invoke(BeanELResolver.java:467)
javax.el.CompositeELResolver.invoke(CompositeELResolver.java:246)
org.apache.el.parser.AstValue.getValue(AstValue.java:159)
org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:189)
org.apache.myfaces.view.facelets.el.ContextAwareTagValueExpression.getValue(
                                          ContextAwareTagValueExpression.java:96)
javax.faces.component._DeltaStateHelper.eval(_DeltaStateHelper.java:246)
javax.faces.component.UIOutcomeTarget.getOutcome(UIOutcomeTarget.java:50)
org.apache.myfaces.shared.renderkit.html.HtmlRendererUtils.getOutcomeTargetHref(
                                          HtmlRendererUtils.java:1542)
org.apache.myfaces.shared.renderkit.html.HtmlLinkRendererBase.renderOutcomeLinkStart(
                                          HtmlLinkRendererBase.java:908)
org.apache.myfaces.shared.renderkit.html.HtmlLinkRendererBase.encodeBegin(
                                          HtmlLinkRendererBase.java:143)
javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:502)
javax.faces.component.UIComponent.encodeAll(UIComponent.java:744)
javax.faces.component.UIComponent.encodeAll(UIComponent.java:758)
javax.faces.component.UIComponent.encodeAll(UIComponent.java:758)
org.apache.myfaces.view.facelets.FaceletViewDeclarationLanguage.renderView(
                                    FaceletViewDeclarationLanguage.java:1900)
org.apache.myfaces.application.ViewHandlerImpl.renderView(ViewHandlerImpl.java:285)
com.ocpsoft.pretty.faces.application.PrettyViewHandler.renderView(
                                    PrettyViewHandler.java:163)
javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:59)
org.apache.myfaces.tomahawk.application.ResourceViewHandlerWrapper.renderView(
                                    ResourceViewHandlerWrapper.java:93)
com.idex.auctions.ui.CustomViewHandler.renderView(CustomViewHandler.java:98)
org.apache.myfaces.lifecycle.RenderResponseExecutor.execute(RenderResponseExecutor.java:115)
org.apache.myfaces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:241)
javax.faces.webapp.FacesServlet.service(FacesServlet.java:199)
com.ocpsoft.pretty.PrettyFilter.doFilter(PrettyFilter.java:126)
com.ocpsoft.pretty.PrettyFilter.doFilter(PrettyFilter.java:118)

Answer 1

The exception:

org.hibernate.AssertionFailure: null id in entry (don't flush the Session after an exception occurs)

Tells us that the session exception has happened before the point where this org.hibernate.AssertionFailure is thrown.

To be exact, the org.hibernate.AssertionFailure is thrown when the session.flush() is happening, not the point where the error ocurred.

The above is a fact, thus a possible conclusion from it is: something could be suppressing the original exception.

So look for other possible points of error: A save() or saveOrUpdate() is possibly trying to persist an entity with a null field where, in the table, the column is NOT NULL?

---

TIP: To help in the debugging, try adding a session.flush() after every interaction with the Session object (e.g. session.save(obj), session.merge(obj), etc.), this will hopefully cause the org.hibernate.AssertionFailure to happen earlier, closer to where the real problem is taking place. (Of course, after the debugging, remove those session.flush().)

In my case, the **real** exception was taking place inside a `try/catch {}` block where the `catch` suppressed the exception (didn't rethrow or warn me about it).

Answer 2

I would bet for a concurrency issue but it may occur at different levels:

• a hibernate session may be shared between different users if the classical "open session in view" pattern is not properly implemented
• an entity is shared between two user sessions because of improper hibernate cache settings
• a JDBC connection is shared between two different hibernate session (less likely)

Apart from these potential sources of troubles, I would remove c3p0 (maybe just rumors...) as your stack already provides DataSource with connection pooling integrated with the transaction manager.

Answer 3

The @asdcjunior has answered correctly. Something has happened before the exception is thrown.

In that kind of situations (it happens often on integration tests when you dealing with single transaction for one test - for example @Transaction annotation) I'm invoking the method:

session.clear()

It helps because all the 'dirty' objects are removed from current session so when the next flush is executed the problem does not appear.

Example flow:

• insert the assignment entity (many-to-many relation with constraint that could exist only single assignment) -> everything ok
• insert the same assignment entity one more time -> everything ok, controller in this case return some kind of bad request exception, under the hood Spring throws the IntegrityViolationException -> in test everything looks ok
• get the repository and execute findAll().size() to check the count of existed assigned to be sure that we have only single assignment -> the mentioned exception is thrown ;/ what happend? on the session exist still dirty object, normally the session would be destroyed (controller return error) but here we have the next assertions to check regarding database, so the solution here is additional session.clear() before next db related method executions

Example correct flow:

• insert the assignment entity
• insert the same assignment entity
• session.clear()
• get the repository and execute findAll().size()

Hope it helps ;)

Answer 4

I was facing this issue I just add try catch block and in catch block I wrote seesion.clear(); now I can proceed with the rest of records to insert in database.

Answer 5

You are probably hitting some Hibernate bug. (I'd recommend upgrading to at least Hibernate 3.3.2.GA.)

Meanwhile, Hibernate does better when your ID is nullable so that Hibernate can always tell the difference between a new object that has not yet been persisted to the database and one that's already in the database. Changing the type of addressID from long to Long will probably work around the problem.

The stack trace you provided shows that you are seeing the problem on a query because your query is forcing buffered writes to be flushed to the database before the query is executed and that write is failing, probably with the same insert problem other people are seeing.

Answer 6

OK, I continued researching based among other things on other answers in this thread. But in the end, since we were up against a production deadline, I had to choose the emergency rout. So instead of figuring out hibernate I did these two things:

1. Removed a jQuery library I was using to grab focus on one of the forms. I did this because I read somewhere that this type of bug may happen due to a form posting a null value -- causing the null id down the line. I suspected the jQuery library may not sit well with PrimeFaces, and cause some form to malfunction. Just a hunch.

2. I killed the hibernate implemented relationship I had between user and address. (just one required, not one to many) and wrote the code myself when needed. Luckily it only affected one page significantly, so it wasn't much work.

The bottom line: we went live and the application has been running for several days without any errors. So this solution may not be pretty -- and I'm not proud of myself -- but I have a running app and a happy client.

Answer 7

org.hibernate.AssertionFailure: null id in entry (don't flush the Session after an exception occurs)

This just happened to us and I thought I'd add some details for posterity. Turns out that we were trying to create an entity with a duplicate field that violated a condition:

Caused by: org.hibernate.exception.ConstraintViolationException: Duplicate entry '' for key
'Index_schools_name'

This exception however was being masked because hibernate was trying to commit the session even though the create failed. When the created failed then the id was not set hence the assert error. In the stack trace we could see that hibernate was committing:

at org.springframework.orm.hibernate4.HibernateTransactionManager.doCommit
(HibernateTransactionManager.java:480)

It should have been rolling back the session, not committing it. This turned out to be a problem with our rollback configuration. We are using the old XML configs and the exception path was incorrect:

<prop key="create*">PROPAGATION_REQUIRED,-org.x.y.LocalException</prop>

The LocalException path was incorrect and hibernate didn't throw an error (or it was buried in the startup log spew). This would probably also be the case if you are using the annotations and don't specify the right exception(s):

// NOTE: that the rollbackFor exception should match the throws (or be a subclass)
@Transactional(rollbackFor = LocalException.class)
public void create(Entity entity) throws AnotherException {

Once we fixed our hibernate wiring then we properly saw the "duplicate entry" exception and the session was properly being rolledback and closed.

One additional wrinkle to this was that when hibernate was throwing the AssertionFailure, it was holding a transaction lock in MySQL that then had to be killed by hand. See: https://stackoverflow.com/a/39397836/179850

Answer 8

Problem flow :

1. You create a new transient entity instance (here an Address instance)
2. You persist it to the database (using save, merge or persist in hibernate Session / JPA EntityManager)
3. As the entity identifier is generated by the database hibernate has to trigger the database insertion (it flushes the session) to retrieve the generated id
4. The insert operation trigger an exception (or any pending unflushed change in the session)
5. You catch the exception (without propagating it) and resume the execution flow (at this point your session still contains the unpersisted instance without the id, the problem is that hibernate seems to consider the instance as managed but the instance is corrupted as a managed object must have an id)
6. you reach the end of your unit of work and the session is automatically flushed before the current transaction is committed, the flush fails with an assertion failure as the session contains a corrupted instance

You have many possible ways to mitigate this error :

• Simplest one and as hibernate stands "don't flush the Session after an exception occurs" ie. immediately give up and roll back the current transaction after a persistence exception.
• Manually evict (JPA : detach) the corrupted instance from the session after catching the error (at point 5, but if the error was triggered by another pending change instead of the entity insert itself, this will be useless)
• Don't let the database handle the id generation (use UUID or distributed id generation system, in this case the final flush will throw the real error preventing the persistence of the new instance instead of an hibernate assertion failure)

Answer 9

This happened to me in the following situation:

1. New entity is persisted.

2. Entity is configured with javax.persistence.EntityListeners. javax.persistence.PostPersist runs.

3. PostPersist needs some data from the database to send a message via STOMP. A org.springframework.data.repository.PagingAndSortingRepository query is executed.

4. Exception.

I fixed it by using the following in the EntityListeners:

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
import java.time.Instant;
...

ThreadPoolTaskScheduler scheduler = ApplicationContextHolder.getContext().getBean(ThreadPoolTaskScheduler.class);
scheduler.schedule(() -> repository.query(), Instant.now());

Where ApplicationContextHolder is defined as:

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;

@Component
public class ApplicationContextHolder implements ApplicationContextAware {

    private static ApplicationContext context;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        context = applicationContext;
    }

    public static ApplicationContext getContext() {
        return context;
    }
}

Answer 10

In my case the problem was the length parameter of an entity's field. When I tried to save an object with too long String value in one of its fields, I got the error. The solution was to set the proper value of parameter "length" in hibernate configuration.

<property name="status" type="string" length="150" not-null="false" access="field"/>

It can also be done with annotation @Length like that:

@Length(max=150)
private String status;

The hibernate exception's message was very misleading in my case, as was stacktrace. The fastest way to locate where the problem occures is to follow your code with debugger and evaluate session.flush(); after every save() and saveOrUpdate() method.

Answer 11

This is nothing to do with the Query that is being executed. This just triggers the flush. At this point Hibernate is trying to assign an identifier to the entity and seems to have failed for some reason.

Could you try changing the generator class:

<generator class="identity"/>

see if that makes a difference. Also have you made sure that the database you have deployed has the correct auto-incrementing column set up on the table?

It sounds like your issue is similar to this one.

Answer 12

Changing the generator class:

<generator class="identity" />

to

<generator class="assigned" />

Answer 13

I have the same exception too, in hibernate config file:

<property name="operateType" type="java.lang.Integer">
        <column name="operate_type" not-null="true" />
 </property>

when pass null value at object, occur exception

 "org.hibernate.AssertionFailure: null id in com.idex.auctions.model.Address entry",

I think the reason because Hibernaye will check 'not-null' property, so, remove 'not-null' property or set 'not-null' for 'false', will resolve the problem.

Answer 14

Sometimes this happens when length of string is greater than that allowed by DB.

DataIntegrityViolationException translates to this exception which is a weird behavior by hibernate.

So if you have Column annotation on the String field of the entity with length specified and the actual value is greater than that length, above exception is thrown.

Ref: https://developer.jboss.org/thread/186341?_sscc=t

Answer 15

org.hibernate.AssertionFailure: null id in entry (don't flush the Session after an exception occurs)

Your getting this error while using the save method, if your maintaining the version history of the user activity and try to set the following values setCreatedBy(1); setModifiedBy(1); setCreationDate(); setChangeDate(); } You will get the above error to solve this you need to create the following columns on table.

Created_By Modified_By Creation_Date Change_Date if you are getting same error while Update method to solve this problem Just you need to change the Update() method to merge() method that it i hope helped you.

Answer 16

I had the same error. In my case it was because before this exception I executing create query with exception. Exception is caught and don't rollback the transaction in catch block. Then I use this broken transaction in other operation and after a few time I got the same exception. At first I set flush mode to manual

public final Session getCurrentSession()  
{
    Session session = sessionFactory.getCurrentSession();
    session.setFlushMode(FlushMode.MANUAL);
    return session;
}

Then I got another exception, that explained to me what happened in fact. Then I done transaction rollback in catch block of my create method. And it helped to me.

Answer 17

I'm hitting the same error when I make session.getCurrentSession.refresh(entity) it looks more like a bug to me instead of an issue with my code. I'm getting this error in a unit test when I'm trying to refresh an entity in the beginning of a test and that entity is created in the test setup (annotated with junit's @Before). What is strange is that I'm creating 3 entities from the same class with random data at the same time and by the same way in the setup and I can refresh the first two created but the refresh fails for the last one. So for example If I create 3 entities User in the test setup I can refresh user1 and user2 and it fails for user3. I was able to resolve this by adding session.flush() at the end of the code that is creating the entity in the setup. I don't get any errors and I should but I cannot explain why the extra flush is needed. Also I can confirm that the entities are actually in the test DB even without flush because I can query them in the test but still failing the refresh(entity) method.

Answer 18

In my case, I traced out the error and found that I had not marked my table's primary key i.e. 'ID' as 'Auto_Increment' AI. Just tick the AI checkbox and it would work.

Answer 19

I don't know if im late or not, but my issue here was that i was opening an transaction and commiting -> flushing -> closing after the request. However between those did i have a nhibernate save() operator which does this automatically, in that case it complained.

Threw exception:

session.BeginTransaction();
model.save(entity);
session.Transaction.commit();

Solved for me

model.save(entity) //this one should open transaction, save and commit/flush by itself

However alot of people says that you should use both, ex NHibernate: Session.Save and Transaction.Commit.

But for some reason does it work for me now without transactions..

Answer 20

Roll back your transaction in the catch block