Re: [j-devel] need to customize print-object for a java class

[Alan R. <ala...@gm...>]

Also, I get:

(defmethod print-object ((obj (jclass "java.net.URI")) stream)
(print-unreadable-object (obj stream :identity t :type t)))
-> ; Evaluation aborted.

-Alan


2010/1/14 Alan Ruttenberg <ala...@gm...>:
> Where's this implemented? It doesn't work for me because jclass doesn't find classes on the dynamically extended classpath I use.
>
> Would this method be called when a backtrace used in slime is constructed?
>
> Thanks,
> Alan
>
> On Thu, Jan 14, 2010 at 9:38 AM, Alessio Stalla <ale...@gm...> wrote:
>> On Thu, Jan 14, 2010 at 3:33 PM, Alan Ruttenberg
>> <ala...@gm...> wrote:
>>> The Jena toolkit has antisocially defined the toString method of an
>>> important object to be computationally expensive - it triggers a
>>> description logical classification process in some cases, something
>>> which can blow out memory or take a very very long time.
>>>
>>> Therefore I need to be able to override that behavior so that if I
>>> happen to get a stack trace or other wise cause one to be printed
>>> toString is not called.
>>>
>>> As far as I can tell, it seems that the case of printing a java object
>>> is handled by
>>>
>>> public String writeToString()  in JavaObject.java
>>>
>>> An approach that makes sense to me would be to have this method look
>>> for an eql method with the class of the object as specializer.
>>>
>>> (defmethod java-object-to-string ((class (eql (load-time-value
>>> (find-java-class "com.hp.hpl.jena.ontology.impl.OntModelImpl"))))))
>>> ..)
>>>
>>> and if such a method exists, call it instead of using the default
>>> implementation.
>>>
>>> Other ideas welcome.
>>
>> I believe
>>
>> (defmethod print-object ((obj (jclass "com.foo.whatever")) stream) ...)
>>
>> should do, at least when the printing is done in Lisp through the
>> standard CL printing functions.
>>
>> hth,
>> Ale
>>
>
>