New Componentized Input / Output ModularDatabaseActions gone
Now, that the race condition with HSQLDB is sorted out I have finally committed the reworked "new" database actions in scratchpad. As announced such a long time ago that probably no-one will remember they come with new input, output, and database autoincrement components that are open to be used by other sitemap components as well. Why do we need to componentize input and output? There are so many different sources of data to work with, request parameters, request headers, request attributes, session attributes, cookies to name a few. Currently, we need to have e.g. a WildcardMatcher for every one of the above inputs. With a componentized structure we need to combine only a WildcardMatcher with the input we would like to use. Two example matchers are included to illustrate how it works. But it's not only matchers: actions and selectors can make use of it as well. Why don't we use Java generics instead? Good question. Perhaps because they're scheduled for JDK 1.5 but since we bundle pizza javac with cocoon we could use them now. With the database actions I have made the experience that I needed input from many different sources at the same time. Generics wouldn't help here. ModularDatabaseActions are gone? Not really, they've moved to a new home in their own package. And as the packages name is org.apache.cocoon.acting.modular the "modular" part was dropped from the name. Thus they are just called "DatabaseAddAction" for example. What is so great about the "new" DatabaseActions that I should switch to them? First of all, they know about autoincrement columns in HSQLDB, MySQL, and Informix. And it is really easy to extent it to your DBMS if you use a different one. Second, you can put your complete database schema in one file and refer to selected tables at will. Third, all database operations can span multiple rows and tables. Fourth, input for columns is very flexible. Is there a reason why I shouldn't switch? Yes, the descriptor file syntax has changed in incompatible ways to allow the new features. I want to have a look at it. Is there a demo? Yes! Build CVS with "-Dinclude.scratchpad.libs=yes" and copy the directory $COCOON_CVS/src/scratchpad/webapps/mount/mod-db to $COCOON/mount with $COCOON_CVS being the location where your CVS checkout resides and $COCOON being the location where the expanded cocoon.war file is located. Point your browser to "mount/mod-db/" relative to cocoon and enjoy. Usually, this would be http://localhost:8080/cocoon/mount/mod-db/ What is next? Two "meta" modules are in the works for SQL99 complex types like row types and collections. They will obtain their input from any other input module and produce Objects that can be inserted into such columns. Have fun! Chris. -- C h r i s t i a n H a u l [EMAIL PROTECTED] fingerprint: 99B0 1D9D 7919 644A 4837 7D73 FEF9 6856 335A 9E08 --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, email: [EMAIL PROTECTED]
