What you need is a hook that says:
instantiate an instance of class <class name>
and you replace
Class.forName("xxx").newInstance()
with
mgr.getClassInstantiator("xxx").newInstance()
Or, you can define a proxy that takes an original object in its
InstanceContext. It can delegate each method to the instance context
value and advise each method with the advice. See IoC code for
examples.
Again, part of Plastic is that only Plastic can instantiate the
transformed class, because the transform class picks up dependencies
from outside the class itself that have to come in through the
constructor.
I have been thinking of making the StaticContext a static field of the
class rather than the constructor, and providing an option to
instantiate the class via a default constructor instead of via
Plastic. I'm not sure that would solve everyone's issues.
On Fri, Jul 29, 2011 at 6:19 PM, Josh Canfield <joshcanfi...@gmail.com> wrote:
>> I'm not sure what you are trying to do.
>
> Sorry, I wasn't very clear. I want to "advise" some services in an
> application that isn't being built using tapestry. First usage will be
> for adding performance monitoring, but other usages are envisioned.
> The server is using ATG's Nucleus for service bean creation and
> dependency injection.
>
> I'm trying to work out a minimally intrusive way to build in some AOP
> without resorting to a build time rewriting. I have a trivial case
> working now, but it required moving my service interface out of the
> plastic managed package.
>
> Since I don't have _much_ control over packaging in the project that
> I'm doing this for so my next step is to investigate non-package based
> class filters.
>
> Josh
>
> On Fri, Jul 29, 2011 at 5:14 PM, Howard Lewis Ship <hls...@gmail.com> wrote:
>> I'm not sure what you are trying to do.
>>
>> You can use Plastic to create proxies around ordinary classes, as long
>> as the classes conform to an interface (this is what Tapestry IoC does
>> extensively).
>>
>> Plastic rewrites your classes and, among other things, adds a new
>> constructor, and invalidates the other constructors (they throw an
>> exception). The new constructor gets a internal StaticContext object
>> that contains various injected things, and an InstanceContext object
>> that contains per-instance values ... in Tapestry terms, the
>> InstanceContext holds the ComponentResources object.
>>
>> BTW, I have a plan for extending Plastic (and therefore Tapestry) to
>> allow non-private fields ... public fields will still be verboten, but
>> other fields types will be allowed. It's just a matter of doing minor
>> rewrites on any incidental inner classes loaded with the top-level
>> (i.e., component) classes.
>>
>> On Fri, Jul 29, 2011 at 3:25 PM, Josh Canfield <joshcanfi...@gmail.com>
>> wrote:
>>> Interesting. I imagine that your tests work because you're using
>>> groovy and not trying to access the class that you've transformed as
>>> it's actual type.
>>>
>>> @Test
>>> public void monitor() {
>>> String rootPackage = "org.apache.tapestry5.monitor.test";
>>> DefaultMonitorNameGenerator nameGenerator = new
>>> DefaultMonitorNameGenerator(rootPackage);
>>> MonitoredProxyFactoryImpl monitoredProxyFactory = new
>>> MonitoredProxyFactoryImpl(nameGenerator, rootPackage);
>>>
>>> // The following results in
>>> // java.lang.ClassCastException:
>>> org.apache.tapestry5.monitor.test.FakeService cannot be cast to
>>> org.apache.tapestry5.monitor.test.FakeService
>>> FakeService monitor =
>>> monitoredProxyFactory.monitor(FakeService.class);
>>>
>>> monitor.publicMethod();
>>> }
>>>
>>> Is what I'm trying to do feasible without replacing the context ClassLoader?
>>>
>>> On Fri, Jul 29, 2011 at 3:08 PM, Taha Hafeez <tawus.tapes...@gmail.com>
>>> wrote:
>>>> Hi Josh
>>>>
>>>> This might help
>>>>
>>>> http://tawus.wordpress.com/category/plastic/
>>>>
>>>> regards
>>>> Taha
>>>>
>>>> On Fri, Jul 29, 2011 at 11:25 PM, Howard Lewis Ship <hls...@gmail.com>
>>>> wrote:
>>>>> On Fri, Jul 29, 2011 at 10:19 AM, Josh Canfield <joshcanfi...@gmail.com>
>>>>> wrote:
>>>>>> I'd like to integrate some advice used in a tapestry web project into
>>>>>> a non-tapestry web project. I can add a dependency on plastic, but not
>>>>>> a tapestry-ioc.
>>>>>>
>>>>>> I'm at the experimental stage at this point and I've hit a snag. I
>>>>>> figure I can wade around for a couple hours, or Howard can whip up in
>>>>>> example off the top of his head.
>>>>>>
>>>>>> Here's some pieces of code.
>>>>>>
>>>>>> plasticManager = PlasticManager
>>>>>> .withContextClassLoader()
>>>>>> .packages(Collections.singleton(basePackage))
>>>>>> .create();
>>>>>>
>>>>>>
>>>>>> public <T> T monitor(Class<T> monitoredClass, Object...
>>>>>> constructorParams) {
>>>>>>
>>>>>> return plasticManager.createClass(monitoredClass, new
>>>>>> PlasticClassTransformer() {
>>>>>>
>>>>>> public void transform(PlasticClass plasticClass) {
>>>>>>
>>>>>> // At this point plasticclass has methodNames, but no methods so the
>>>>>> following fails to find my annotation.
>>>>>> // Do I need to manually override the methods?
>>>>>>
>>>>>> List<PlasticMethod> methods =
>>>>>> plasticClass.getMethodsWithAnnotation(Monitor.class);
>>>>>> for (PlasticMethod method : methods) {
>>>>>> final Stopwatch stopwatch =
>>>>>> createStopwatch(method.getAnnotation(Monitor.class), method);
>>>>>> logger.debug("Adding advice for {}",
>>>>>> stopwatch.getName());
>>>>>> method.addAdvice(new MonitorAdvice(stopwatch));
>>>>>> }
>>>>>> }
>>>>>>
>>>>>> }).newInstance();
>>>>>> }
>>>>>>
>>>>>> ---------------------------------------------------------------------
>>>>>> To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org
>>>>>> For additional commands, e-mail: users-h...@tapestry.apache.org
>>>>>>
>>>>>>
>>>>>
>>>>> I think what you are missing is that you don't create a class (that's
>>>>> for creating proxies and such, the monitoredClass you pass in becomes
>>>>> the base class).
>>>>>
>>>>> What you want to do is wrap your logic up your PlasticClassTransformer
>>>>> inside a StandardDelegate (a trivial internal class).
>>>>>
>>>>> You can then ask the manager to getClassInstantiator() and
>>>>> newInstance() that to get your advised and instantiated instance.
>>>>>
>>>>>
>>>>> --
>>>>> Howard M. Lewis Ship
>>>>>
>>>>> Creator of Apache Tapestry
>>>>>
>>>>> The source for Tapestry training, mentoring and support. Contact me to
>>>>> learn how I can get you up and productive in Tapestry fast!
>>>>>
>>>>> (971) 678-5210
>>>>> http://howardlewisship.com
>>>>>
>>>>> ---------------------------------------------------------------------
>>>>> To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org
>>>>> For additional commands, e-mail: users-h...@tapestry.apache.org
>>>>>
>>>>>
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org
>>>> For additional commands, e-mail: users-h...@tapestry.apache.org
>>>>
>>>>
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org
>>> For additional commands, e-mail: users-h...@tapestry.apache.org
>>>
>>>
>>
>>
>>
>> --
>> Howard M. Lewis Ship
>>
>> Creator of Apache Tapestry
>>
>> The source for Tapestry training, mentoring and support. Contact me to
>> learn how I can get you up and productive in Tapestry fast!
>>
>> (971) 678-5210
>> http://howardlewisship.com
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org
>> For additional commands, e-mail: users-h...@tapestry.apache.org
>>
>>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org
> For additional commands, e-mail: users-h...@tapestry.apache.org
>
>
--
Howard M. Lewis Ship
Creator of Apache Tapestry
The source for Tapestry training, mentoring and support. Contact me to
learn how I can get you up and productive in Tapestry fast!
(971) 678-5210
http://howardlewisship.com
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org
For additional commands, e-mail: users-h...@tapestry.apache.org
