On Jan 11, 2012, at 309AM, Greg Trasuk wrote:
>
> On Wed, 2012-01-11 at 01:01, Peter Firmstone wrote:
>> You could try Dennis Reedy's Groovy Configuration Provider, that'll give
>> you Pojo's with Java like syntax. We still need to add an ant task to
>> generate the groovy javadoc too.
>>
>> It would be nice to see that system used by default.
>>
>
> Just curious...What is the advantage of Groovy's syntax over
> ConfigurationFile?
You get to use *real* code in your configuration. From my experience people are
usually very confused with configuration file syntax, and why it is java-like
but you cannot use any logic. Just to show a simple example for reggie (I hope
you'll be able to get the gist of it), figuring out the correct unicast
discovery host based on a system property would be as follows (note the
initialUnicastDiscoveryProperty is declared just as a property as well):
@Component('com.sun.jini.reggie')
class ReggieConfig {
int initialUnicastDiscoveryPort = 10500
String[] getInitialMemberGroups() {
def groups = [System.getProperty(Constants.GROUPS_PROPERTY_NAME,
System.getProperty('user.name'))]
return groups as String[]
}
String getUnicastDiscoveryHost() {
String host = java.net.InetAddress.getLocalHost().getHostAddress()
String value = System.getProperty("java.rmi.server.hostname")
if(value != null) {
host = java.net.InetAddress.getByName(value).getHostAddress()
}
return host
}
}
Inheritance is supported as well, etc.. etc ...
I also use a DynamicConfiguration (extends AbstractConfiguration) class as
well. Its use is shown here:
DynamicConfiguration config = new DynamicConfiguration();
config.setEntry("org.rioproject.watch", "collectionSize", collectionSize);
Watch watch = construct2("watch", config);
Lastly, I recall Calum Shaw-Mackay was doing work with the Glyph project that
was using annotations to wire up configs with annotations.
>
> Also, I just had an interesting thought: What if a service deployer (as
> in "ServiceStarter is a service deployer") were to scan the service
> class for JSR330 @Inject annotations and plug in values taken from the
> config file?
Sure, that would be nice (just be careful not to fill up the perm-gen space
when looking for annotations though). I'm wondering though how you would map
the component and name to the property or method to be set.
Dennis
