Issue with hibernate/Spring transaction management

Question

I am facing a problem with Spring Transaction management. I am using hibernate as ORM framework. And below is my spring for transaction management.

  <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
    <property name="sessionFactory">
      <ref bean="sessionFactory"/>
    </property>
</bean>


  <bean id="abstractDao"
      class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean" abstract="true" lazy-init="true">
    <property name="transactionManager">
        <ref bean="transactionManager"/>
    </property>
    <property name="transactionAttributeSource">
        <ref bean="transactionAttributeSource"/>
    </property>   
    <property name="postInterceptors">
      <list>
        <ref bean="finderIntroductionAdvisor"/>
      </list>
    </property>       
</bean>
   <bean id="abstractService"
      class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean" abstract="true" lazy-init="true">
    <property name="transactionManager">
        <ref bean="transactionManager"/>
    </property>
    <property name="transactionAttributeSource">
        <ref bean="transactionAttributeSource"/>
    </property>   
</bean>

I am basically following genericDao approach as mentioned here so My DaoObject are used to fetch the Domain objects and service classes have DAO objects to maipulate them.

issue i am facing : i am querying a large dataset and loading the result in a list inside the service class. i have marked service class as @transactional(readonly ="true").

to handle some reuirement i have changed all the getters of boxed primitive to

  @Column(name = "students")
public Long getStudents() {
    if(students== null){
        return 0l;
    }
    return this.students;
}

whenever i load all the dataset via a named query. multiple update queries are fired subsequently to update the dataset. I debugged that and came to know that this is occuring because of transaction.commit. as hibernate is treating my entities as dirty.

is there a way i can avoid this . i know Flushmode.never could be of help but in my application seesion object is not exposed so i do not have access to it. is there any other way or some mapping change which can help me ?

The only scenario when I've seen hibernate trying to issue updates or deletes after doing just a query, is when the mapping is wrong which makes hibernate think that certain elements were deleted or updated. I'm just mentioning this as there's a big chance that this is the underlying problem. — Augusto
Could I suggest changing the title of the question? Since SO is considered to be a reference for the future it's nice to have questions be browsable as well as searchable. — Bill K

axtavt axtavt · Accepted Answer · 2011-09-13T15:21:24

In addition to Xavi López's answer, another option is to separate persistent property handled by Hibernate from the transient property that conform to your requirement. For example, as follows:

@Column(name = "students")
public Long getStudentsInternal() {
    return students;
}

@Transient
public Long getStudents() {
    if (students == null) {
        return 0l;
    }
    return students;
}

You can also configure Hibernate to use fields instead of properties by moving annotations to them, it will solve your problem as well (note that the placement of annotations should be consitent for all fields of the entity, or you can use @Access to configure an exclusion):

@Column(name = "students")
private Long students;

public Long getStudents() {
    if (students == null) {
        return 0l;
    }
    return students;
}

Issue with hibernate/Spring transaction management

2 Answers