Configuration

Jacson configuration is a XML language, therefore one could think a DTD could describe legal input. This is not entirely true, since plugin classes can define their very own XML structure.

Runnable examples are the *.conf files in the samples directory.

For some explanation, this is the file head.conf which achieves something like the UNIX head command.

            
01: <?xml version="1.0" encoding="iso-8859-1"?>
02: <!--
03:   Jacson demo.
04:  Uses the Head to obtain something similar to UNIX head.
05:  -->
06: <application>
07:     <se:param se:name="count" se:value="2"/>
08:     <jacson>
09:         <filter se:this="HeadFilter" count="${count}"/>
10:         <eval se:this="LoggingEvaluator"/>
11:         <!-- 
12:           Value printing report strips away all the structur
13:           from the output data. Additionally it can do a simple
14:           selection on the output: The "section" argument select
15:           certain path names.
16:         -->
17:         <report se:this="ValuePrintingReport">
18:             <section>lines/log/chunk</section>
19:             <!--
20:             <test>true</test>
21:             -->
22:         </report>
23:     </jacson>
24: </application>
            
          

• Line 07 defines a variable ${count}, this param defaults to 2, but can be overriden by either the commandline with the Jacson driver program or with a property count from the calling Ant Project.
• Line 09 sets up the filter to filter the demanded number of lines.
• Line 10 sets the LoggingEvaluators which simply logs all chunks to the JacsonReport.
• Line 17,18 set up the ValuePrintingReport so that it only logs the (filtered) chunks. To understand the <section> it is useful to substitute this Report by the XMLReport and have a look at the generated output structure.