readonly transaction attribute doesn't seem to work. [SPR-114]

[spring-projects-issues]

Mike Youngstrom opened SPR-114 and commented

If I wrap a simple spring bean into a TransactionInterceptor and aHibernateInterceptor and set all methods to "readonly" and attempt to delete an object using hibernate and then query hibernate again the object is perminately deleted. Conversely if I delete the item and then do not attempt to query hibernate again then the item is correctly not deleted.

TestBean.java

public class TestBean implements Executeable {
    public HibernateTemplate hibernateTemplate;

    public String execute() {
        hibernateTemplate.execute(new HibernateCallback() {
            public Object doInHibernate(Session session) throws HibernateException {
                List accounts = session.find("from KeyValue");
                System.out.println(accounts.size());
                session.delete(accounts.get(0));
//If you comment out the line below this then everything works as expected.
                accounts = session.find("from KeyValue");
                System.out.println(accounts.size());
                return null;
            }
        });
        return null;
    }

    public void setHibernateTemplate(HibernateTemplate hibernateTemplate) {
        this.hibernateTemplate = hibernateTemplate;
    }
}

Executeable.java

public interface Executeable {

    public String execute();
}

pertinate applicationContext.xml entries.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
	<bean id="mySessionFactory" class="org.springframework.jndi.JndiObjectFactoryBean">
		<property name="jndiName">
			<value>java:/hibernate/HibernateFactory</value>
		</property>
	</bean>
    <bean id="myHibernateInterceptor" 
        class="org.springframework.orm.hibernate.HibernateInterceptor">
        <property name="sessionFactory">
            <ref bean="mySessionFactory"/>
        </property>
    </bean>
	<bean id="matchAllWithPropReq" class="org.springframework.transaction.interceptor.NameMatchTransactionAttributeSource">
		<property name="properties">
		   <props>
				<prop key="*">PROPAGATION_REQUIRED,readOnly</prop>
			</props>
		</property>
	</bean>
	<bean id="transactionManager" class="org.springframework.transaction.jta.JtaTransactionManager">
		<property name="transactionManagerName">
			<value>java:/TransactionManager</value>
		</property>
	</bean>
    <bean id="hibernateTemplate" class="org.springframework.orm.hibernate.HibernateTemplate">
    	<property name="sessionFactory">
    		<ref local="mySessionFactory"/>
    	</property>
    </bean>
    <bean id="myTransactionInterceptor" 
        class="org.springframework.transaction.interceptor.TransactionInterceptor">
        <property name="transactionManager">
            <ref bean="transactionManager"/>
        </property>
        <property name="transactionAttributeSource">
        	<ref local="matchAllWithPropReq"/>
        </property>
    </bean>
	<bean id="Bean1" class="TestBean" singleton="false">
		<property name="hibernateTemplate">
			<ref local="hibernateTemplate"/>
		</property>
	</bean>
    <bean id="myBean1" class="org.springframework.aop.framework.ProxyFactoryBean">
        <property name="proxyInterfaces">
            <value>Executeable</value>
        </property>
        <property name="interceptorNames">
            <list>
                <value>myTransactionInterceptor</value>
                <value>myHibernateInterceptor</value>
            </list>
        </property>
        <property name="target">
        	<ref local="Bean1"/>
        </property>
    </bean>
</beans>

---

Affects: 1.0.1

[spring-projects-issues]

Juergen Hoeller commented

The "readOnly" part of a transaction attribute is just a hint: It tells the database respectively the O/R mapping subsystem to optimize for read-only access. It does not prevent you from performing (or triggering) write operations.

In the Hibernate case, a read-only transaction will simply not attempt to flush on commit. So for example, if you manually invoke flush, you'll still override this. And if you query for an object that you've just deleted, you'll force Hibernate to flush changes to that object to avoid stale data.

The general rule is: Don't use "readOnly" to suppress write operations. Rather, mark actual read-only data access operations as "readOnly" to execute them more efficiently. You're still responsible for coding correct operations; there's no way around this.

Juergen

[spring-projects-issues]

Mike Youngstrom commented

Sounds good. Sorry for the false assumption on what that transaction attribute meant. This issue can be closed. I can't figure out how to do it myself. :)

Mike

[spring-projects-issues]

Juergen Hoeller commented

Clarified semantics of "readOnly" transaction attribute.