TimeZoneRegistryFactory instantiation not OSGI compliant

Hello,

In a OSGI application, when I try to create a TimeZoneRegistryFactory with:

private static final TimeZoneRegistry DEFAULT_REGISTRY = DefaultTimeZoneRegistryFactory.getInstance().createRegistry();

the CalendarValidatorFactory class cannot be instantiated.

The root cause is that AbstractCalendarValidatorFactory instance initialization uses java.util.ServiceLoader#load(java.lang.Class<S>) that uses the Thread.currentThread().getContextClassLoader() classloader to instantiate the class. That does not work in an OSGI application.

We found a workaround:

        ClassLoader currentCl = Thread.currentThread().getContextClassLoader();
        try {
            Thread.currentThread().setContextClassLoader(AbstractCalendarValidatorFactory.class.getClassLoader());
            timeZone = DEFAULT_REGISTRY.getTimeZone(timeZoneId);
        } finally {
            Thread.currentThread().setContextClassLoader(currentCl);
        }

But a more OSGI compliant code should be better.

[benfortuna]

Also, we’ll probably look for a replacement to ServiceLoader that supports all of these:

• OSGi compatible
• Android compatible
• Doesn’t require a container (e.g. OSGi) to work

Probably some form of light-weight dependency injection (e.g. guice, etc.)

[benfortuna]

Starting with release 3.0.5 I’m trying to phase out use of ServiceLoader in main ical4j library.

The plan is that ical4j-extensions library will provide mechanism for dynamically loading extensions using alternatives like ServiceLoader, OSGi, etc.