Bean creation using Spel + hibernate
We are using Spring MVC + its built in support for uploading files. I want to set the maximum upload size utilizing SpEL. The problem is this value comes from our database. So in our old application code, we do a check once we have the file uploaded with the following:
appManager.getAppConfiguration().getMaximumAllowedAttachmentSize();
We then check the file to see if it is larger than this, and proceed based upon the size.
I'd like to replace that code with the following call in our servlet configuration like such:
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver>
<property name="maxUploadSize" value="#{appManager.getAppConfiguration().getMaximumAllowedAttachmentSize()}" />
</bean>
The problem is that upon initialization I receive the following exception:
Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanExpressionException: Expression pa开发者_Python百科rsing failed; nested exception is org.hibernate.LazyInitializationException: could not initialize proxy - no Session
Is there any way to achieve this?
I'd try a differnt approach:
- extend the
org.springframework.web.multipart.commons.CommonsMultipartResolver
- add
org.springframework.beans.factory.InitializingBean
or use@PostConstruct
to write a method that will call theappManager
and set themaxUploadSize
in beans initialization phase, after the configuration file was parsed and all dependencies were injected
For example like this:
public class MyMultipartResolver extends CommonsMultipartResolver {
@Autowired
private AppManager appManager;
@PostConstruct
public void init() {
setMaxUploadSize(
appManager.getAppConfiguration().getMaximumAllowedAttachmentSize());
}
}
Still the maximim upload size will be set on the multipart resolver only once - during the application context initialization. If the value in database changes it will require an application restart to reconfigure the resolver for the new value.
Consider if You don't need to override the CommonsFileUploadSupport#prepareFileUpload()
like this instead:
public class MyMultipartResolver extends CommonsMultipartResolver {
@Autowired
private AppManager appManager;
@Override
protected FileUpload prepareFileUpload(String encoding) {
FileUpload fileUpload = super.prepareFileUpload(encoding);
fileUpload.setSizeMax(
appManager.getAppConfiguration().getMaximumAllowedAttachmentSize());
return fileUpload;
}
}
There is another option that can be useful depending on your case. You can extend PropertiesFactoryBean
or PropertyPlaceholderConfigurer
and obtain some of the properties from your database.
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