Hi all guys,
I've had this mail draft for a long while and I think it's time to
shout it out to get your feedbacks.
Due to my involvement in Apache Commons and being strongly influenced
by the Google-Guice design, I think we could get benefit from a vision
that mixes the power of:
* modularity;
* Embedded DSL.
The current situation is that the sitemap takes tons of Kb of Spring
dependencies (please assume I'm not a big fan of Spring so my POV is
influenced :P) and the sitemap is described via XML. Since we can
still take the XML configuration, I'm sure - but I haven't had the
time to write even a kickoff spike, so I still don't have the proof on
hands - we could simplify the foundation of sitemap design, getting
benefits from the javac using directly the Java language to describe
the sitemap.
What I'd suggest is introducing Sitemap(s) to describe how the
sitemap is organized, i.e.
+-------------------------+
interface Sitemap
{
void configure( SitemapBinder binder );
}
+-------------------------+
where the {{SitemapBinder}} contains a set of APIs to allow describing
the path-matching; a possible case could be:
+-------------------------+
public class MySitemap
implements Sitemap
{
public void configure( SitemapBinder binder )
{
binder.when( "linkmap.xml" )
.newCachingPipeline()
.setStarter( new XMLGenerator(new URL( "feed.xml" ) )
.addComponent( new
XSLTTransformer(this.getClass().getResource("/trax.xslt") )
.setFinisher( XMLSerializer.createXMLSerializer );
...
binder.when( "linkmap2.xml" )
.newCachingPipeline()
.setStarter( new XMLGenerator(new URL( "feed2.xml" ) )
.addComponent( new
XSLTTransformer(this.getClass().getResource("/trax2.xslt") )
.setFinisher( XMLSerializer.createXMLSerializer );
...
}
}
+-------------------------+
that would reflect what in XML would be expressed as:
+-------------------------+
<map:match pattern="linkmap.xml">
<map:generate src="classpath:feed" />
<map:transform src="{lm:transform.linkmap.document}"/>
<map:serialize type="xml" />
</map:match>
...
<map:match pattern="linkmap2.xml">
<map:generate src="classpath:feed2" />
<map:transform src="{lm:transform.linkmap.document}"/>
<map:serialize type="xml" />
</map:match>
...
+-------------------------+
of course, XML looks compact, but please take in consideration that
XML is not type checking, we can get errors at runtime only; that
means that a transformer can be erroneously set as generator, while
using Java APIs it would be notified at compile time.
An AbstractSitemap would help to reduce the `binder` variable verbose
and redundant call:
+-------------------------+
public class MySitemap
extends AbstractSitemap
{
@Override
public void configure()
{
when( "linkmap.xml" )
.newCachingPipeline()
.setStarter( new XMLGenerator(new URL( "feed.xml" ) )
.addComponent( new
XSLTTransformer(this.getClass().getResource("/trax.xslt") )
.setFinisher( XMLSerializer.createXMLSerializer );
...
when( "linkmap2.xml" )
.newCachingPipeline()
.setStarter( new XMLGenerator(new URL( "feed2.xml" ) )
.addComponent( new
XSLTTransformer(this.getClass().getResource("/trax2.xslt") )
.setFinisher( XMLSerializer.createXMLSerializer );
...
}
}
+-------------------------+
we could also work by Sitemap composition:
+-------------------------+
public class MySitemap
implements Sitemap
{
public void configure( SitemapBinder binder )
{
binder.when( "linkmap.xml" )
.newCachingPipeline()
.setStarter( new XMLGenerator(new URL( "feed.xml" ) )
.addComponent( new
XSLTTransformer(this.getClass().getResource("/trax.xslt") )
.setFinisher( XMLSerializer.createXMLSerializer );
...
binder.include( new MySitemap2() );
...
}
}
+-------------------------+
then a special loader is used to create the application:
+-------------------------+
SitemapLoader.load( Sitemap...sitemaps );
+-------------------------+
WDYT?
TIA, all the best,
-Simo
http://people.apache.org/~simonetripodi/
http://www.99soft.org/
