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How to inject an attribute using spring in a type handler?

I'm setting up an application which uses mybatis to map objects to/from the database.
In my mybatis file, I use a typehandler to map one of the objects being sent to the database.
In the typeHandler, I am injecting an attribute using spring #resource.
However, when the typehandler is called, the injected property is always null.
From my research, I have discovered that mybatis sets its configuration before spring loads. That means the bean is cannot be injected into the handler as it is created after.
Does anyone know a solution to this?

Should let spring manage customized type handler, like this:
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="typeHandlers">
<array>
<bean class="com.example.YourCustomTypeHandler">
<!-- inject -->
<property name="property" ref="bean"/>
</bean>
</array>
</property>
</bean>

Suggestion to implement custom bean initialization/creation logic in Spring

In my Java/spring project there are lots of beans configured in an xml like,
<beans>..
<bean id="beanOne" class=...>
<property name="x" value="1"/>
<property name="y" value="something"/>
<property name="z" value="something else"/>
</bean>
</beans>
"beanOne"'s properties(x,y,z) values keep changing for different needs/machines. I can create different xml files having different values, one for each need/machine. But I want to write some custom bean creation logic so that I can define different properties in a single properties (or) json file and the custom class takes care of creating the beans with appropriate values from that single properties (or) json file for all needs/machines.
So how to can I do that in spring? - Extend AbstractFactoryBean, implement FactoryBean, implement BeanFactory, or something else? I just need the logic/skeleton of how to do that using spring.

Follow these steps to do the same,
create the object for your required bean.
Set the required properties for that object, you can fetch it from anywhere you want.
Register that object in beanFactory as a bean.
Reference : https://wordpress.com/post/anilagrawal038.wordpress.com/3

Properties in Spring, accessing within Java app

I have a properties set like so :
<context:property-placeholder
location="file:${catalina.home}/conf/my.properties"
ignore-unresolvable="true" />
they are then referenced in app context (specifically app.email) like so :
<bean id="alertMailMessage" class="org.springframework.mail.SimpleMailMessage">
<property name="to">
<value>${app.email}</value>
</property>
</bean>
However when I try to access that property within an actual pojo, not a spring bean - actually a pojo annotated as a hibernate entity (not the alertMailMessage bean) it is coming back as null ?
#Value("${app.email}")
private String defaultEmailAddress;
I want to use the value of property setting "app.email" elsewhere, other than alertMailMessage, whats the best way ? (alertMailMessage is working fine btw)

You can't set it in a hibernate entity, because hibernate entities are not managed by spring.
Use the #Value annotation in your spring service which creates the hibernate entity, and set it manually if needed. But it looks odd to store a default value in the database, so reconsider that.
As a sidenote: you can have hibernate entities managed by spring if using aspectJ and #Configurable, but that may complicate things unnecessarily.

Spring #Autowired with 2 beans of the same type

I have the following defined.
#Autowired
DaoType1<object1> someDao;
#Autowired
DaoType1<object1> someListDao;
and in my bean definitions I have two beans of the same type
<bean id="someDao" class="com.example.DaoType1" />
<bean id="someListDao" class="com.example.DaoType1" />
The second bean is imported from another xml file if that makes a difference. They have different properties being set as well. Why is spring not throwing an error because 2 beans of the same type have been defined. Does it use the variable names since they match the bean ids. The dao's are different and the functionality works as expected if I had used #Qualifiers for the two different beans.
Here is a more concise version. I've left out other beans since I they are not relevant.
applicationContext.xml
<import resource="classpath:dm-services-crud.xml"/>
<bean id="ruleListCrudService" class="com.idna.dm.service.crud.impl.RuleCrudServiceImpl">
<property name="crudDao" ref="ruleListCrudDao" />
</bean>
dm-services-crud.xml
<bean id="ruleCrudService" class="com.idna.dm.service.crud.impl.RuleCrudServiceImpl">
<property name="crudDao" ref="ruleCrudDao" />
<property name="ruleNetworkOfNodesCrudService" ref="ruleNetworkOfNodesCrudService" />
<property name="elementMappingsCrudService" ref="elementMappingsCrudService" />
<property name="ruleCrudDao" ref="newRuleCrudDao"/>
</bean>
default-autowire is not present in any of my xml files at all.

This appears to be expected behaviour. The documentation says:
byName
Autowiring by property name. Spring looks for a bean with the same name as the property that needs to be autowired. For example, if a bean definition is set to autowire by name, and it contains a master property (that is, it has a setMaster(..) method), Spring looks for a bean definition named master, and uses it to set the property.
I guess this means you have specified default-autowire="byName" in your applicationContext.xml.
However, refactoring may affect this in an unpredictable way. That's why (I think) it is advisable to switch to autowiring by type, and disambiguate the beans by the use of
#Qualifier (as you noted)
#Resource rather than #Autowired (as skaffman noted)

The #Autowired annotation behaves slightly differently to the "autowire by type" specification on xml based bean definitions.
When using annotations you're not technically doing an auto wire... you're setting the value based on the annotation. The autowire annotation has the same function as the xml property element.

spring 3.0 force singleton bean

<bean id="data.emf"
class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean" >
<property name="persistenceUnitName" value="transactions-optional" />
</bean>
from what i know by default all bean are singleton (according to document) but i somehow still getting duplicated creating of entitymanagerfactory. is there any parameter i can set for bean above in spring 3.0 to force singleton? the problem only appear in gae production, on hosted mode, no problem

You can force a bean to be a singleton like this:
<bean scope="singleton" ... >
</bean>
You generally don't need to do this, however, since singleton is the default scope, and there's no way to change the default.
The Spring DEBUG-level logs will generate entries every time a bean is instantiated, so have a look through there to see when and where your bean is being processed.

Maybe the problem doesn't come form the scope. Are you sure you haven't defined another bean in anther place of the program (for example with an annotation) or in another context file? Comment that bean definition and try if it can find a instance of it without declaring it here.