On Tue, 2003-06-10 at 11:06, Shahed Moolji wrote: > By reading the intro to Digester, it looks like the right tool to build such > an application.
I'm partial to Digester, but in the interest of "full disclosure", there is another tool named Castor which might also be of use. It is available from Exolab - http://www.exolab.org . Castor seems to have a lower conceptual barrier to entry, but in terms of performance and usability, I've found Digester to be leaner and more flexible. > 1. Has anyone out there implemented VXML using Digester ? Not I, but it wouldn't be very difficult to implement. From what I see in the VoiceXML 2.0 spec, it should be too difficult to come up with an XML ruleset definition and an object model for VoiceXML 2.0. Please, if you do this consider placing it under an Apache style license and contributing the code. > 2. Are there any good examples that show me how to use digester other than > to parse a config file ? I'm assuming you'd want to parse VoiceXML into some sort of hierarchical object model, that is not dissimilar from the way that RSS is parsed in Digester or the way the config files in Struts are parsed. There are a few places to find examples of using the Digester, EXAMPLE 1. Digester Ships with a "Demo" that can "digest" RSS - Look at the source code of Digester, and you'll see a package org.apache.commons.digester.rss. You'll find two RSS DTDs and Example XML file for RSS, some objects, and a class named RSSDigester.java. http://cvs.apache.org/viewcvs/jakarta-commons/digester/src/java/org/apache/commons/digester/rss/RSSDigester.java?rev=1.5&content-type=text/vnd.viewcvs-markup RSSDigester contains programmatic statements to create a parser for RSS, you can use this as a model for implementing your own Digester. You should take note that the RSSDigester is somewhat obsoleted by the ability to specify digester rule sets in an XML file. Just be aware that, a better approach would involve taking the contents of the configure() function in RSSDigester, putting these into an XML file, and then creating a Digester instance from this configuration file. EXAMPLE 2. The Test cases: http://cvs.apache.org/viewcvs/jakarta-commons/digester/src/test/org/apache/commons/digester/ . This might be a little confusing for someone very new to Digester, but once you get a hold of using the Digester from Example 1, looking at the source code for the test cases will shed light on the available feature-set. EXAMPLE 3. Find another project that depends on the commons-digester - You can look at a number of project through jakarta-gump's website, and find a project that depends on Digester - like say the "older brother" of Digester - jakarta-struts. Here is a class similar to RSSDigester for Struts - http://cvs.apache.org/viewcvs/jakarta-struts/src/share/org/apache/struts/config/ConfigRuleSet.java?rev=1.14&content-type=text/vnd.viewcvs-markup As you can see, a number of projects that depend on Struts still use the programmatic definition of the rule sets in Java code. These implementations can all just as easily be implemented using an XML rule set definition. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
