Missing SessionFactory property (filter AutoCloseable from PropertyDescriptors)

[v00d00c0de]

Affects: 5.3.20+

Before 5.3.20 the following code worked as intended (note the use of <util:property-path path="abcEntityManagerFactory.sessionFactory" />: sessionFactory property is accessible in abcEntityManagerFactory bean)

<bean id="abcEntityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean" lazy-init="true">
		... providing the relevant properties ...
</bean>
<bean id="abcHibernateStatisticsMBeanExporter" class="org.springframework.jmx.export.MBeanExporter">
	<property name="server" ref="mbeanServer" />
	<property name="beans">
	   <map>
	      <entry key="org.example:name=abcHibernateStatistics">
		<bean class="org.hibernate.stat.internal.StatisticsImpl">
                    <constructor-arg name="sessionFactory">
                        <util:property-path path="abcEntityManagerFactory.sessionFactory" />
                    </constructor-arg>
                    <property name="statisticsEnabled" value="true"/>
                  </bean>
	      </entry>
	   </map>
	</property>
</bean>

After upgrading from Spring 5.3.18 to 5.3.23 the system fails on startup with the following exception:

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'util:property-path#61ffe4cf': FactoryBean threw exception on object creation; nested exception is org.springframework.beans.NotReadablePropertyException: Invalid property 'sessionFactory' of bean class [com.sun.proxy.$Proxy231]: Bean property 'sessionFactory' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?
	at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:176)
	at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.getObjectFromFactoryBean(FactoryBeanRegistrySupport.java:135)
	at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:377)
	... 72 more
Caused by: org.springframework.beans.NotReadablePropertyException: Invalid property 'sessionFactory' of bean class [com.sun.proxy.$Proxy231]: Bean property 'sessionFactory' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?
	at org.springframework.beans.AbstractNestablePropertyAccessor.getPropertyValue(AbstractNestablePropertyAccessor.java:627)
	at org.springframework.beans.AbstractNestablePropertyAccessor.getPropertyValue(AbstractNestablePropertyAccessor.java:617)
	at org.springframework.beans.factory.config.PropertyPathFactoryBean.getObject(PropertyPathFactoryBean.java:223)
	at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:169)
	... 74 more

This is caused by #28445 which is a part of 5.3.20.

SessionFactory property is no longer accessible: its type is org.hibernate.engine.spi.SessionFactoryImplementor which is AutoCloseable. And according to the new isInvalidReadOnlyPropertyType method added in #28445 it is filtered out of the bean's PropertyDescriptors.

[jhoeller]

I see your point, and there might be a way to fine-tune that rule towards accepting AutoCloseable property types on declaring classes that are AutoCloseable themselves.

That said, there are other ways to express such a dereference in configuration scenarios, e.g. using SpEL:
<constructor-arg name="sessionFactory" value="#{abcEntityManagerFactory.sessionFactory}"/>

Or alternatively, using an intermediate bean definition:

<constructor-arg name="sessionFactory">
    <bean factory-bean="abcEntityManagerFactory" factory-method="getSessionFactory"/>
</constructor-arg>

I would generally recommend either of the two over a JavaBeans property for such purposes.