geronimo-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From David Jencks <>
Subject Re: [POLL] API and Implementation serialization compatibility and upgrading
Date Tue, 17 May 2005 18:39:15 GMT
Slow down a minute.

I just looked at the activemq gbeans used in geronimo currently and 
they appear to use for attributes only types from  As I 
already indicated in a previous post, the possible problems come from 
changing classes used as attributes and changing the GBeanInfo classes 
themselves.  An incompatible change in GBeanInfo classes is very likely 
to require redeployment of everything and redesign of the descriptors.  
Since activemq is only using standard java types as gbean attributes, 
activemq is free to change all their classes as they see fit and make 
none of them serializable as long as the types and names of the gbean 
attributes remain the same.

As far as the form of metadata needed for an IOC container, I currently 
prefer GBeanInfo to the alternatives I am aware of.  I think it's 
important to specify exactly what interface is presented to the 
container, which IIUC spring does not require, and after working a lot 
with the jboss xmlbean implementation and writing the xdoclet xmlbeans 
plugin, I think that xml is perhaps the worst choice possible, and 
javadoc tags not much better.

david jencks

On May 16, 2005, at 4:13 PM, Hiram Chirino wrote:

> Hi,
> From the ActiveMQ viewpoint,  we would rather:
>>   [ ]  We will do our best to ensure the implementations of our APIs 
>> are serialization compatible to future versions of our code.
>>   [X]  We do our best to ensure our public APIs, but use of our 
>> implementations in such a way is not supported by us.
> ActiveMQ standalone does not currently have these serialization issues 
> so it's unfortunate that for us to play nice with Geronimo we would 
> have to add on a Serialization requirement on our GBeans.  It's 
> actually quite unfortunate that ActiveMQ even needs to implement 
> GBeans.  It just proves that the geronimo IOC container is not 
> transparent.  And adding the Serialization requirements makes that 
> even worse.

View raw message