[HAPI-devel] SystemClassLoader and Tomcat Enviroment

[Pier F. S. <p.s...@we...>]

Hello

I tried to run the HAPI under Tomcat enviroment (tomcat 4.1.27) but I found
the following problem:

ca.uhn.hl7v2.HL7Exception: Couldn't create Message object of type ADT_A08
 at ca.uhn.hl7v2.parser.PipeParser.parse(PipeParser.java:222)
 at ca.uhn.hl7v2.app.Responder.processMessage(Responder.java:139)
 at ca.uhn.hl7v2.app.Receiver$Grunt.run(Receiver.java:115)
Caused by: ca.uhn.hl7v2.HL7Exception: No map found for version 2.3.1
 at ca.uhn.hl7v2.parser.Parser.getMessageStructureForEvent(Parser.java:390)
 at ca.uhn.hl7v2.parser.Parser.findMessageClass(Parser.java:263)
 at ca.uhn.hl7v2.parser.PipeParser.parse(PipeParser.java:209)
 ... 2 more

The problem was about the SystemClassLoader. Tomcat, such as many server
applications,
installs a variety of class loaders.
When you deploy a resource (like properties files) under a WebApp, you must
use the
getResourceAsStream() instead of getSystemResourceAsStream() to retrieve
this rosource.

So I have changed:
    InputStream in =
Parser.class.getClassLoader().getSystemResourceAsStream(resource);
in
    InputStream in =
Parser.class.getClassLoader().getResourceAsStream(resource);

in the loadMessageStructures() method of Parser class and all seems to be
ok.

Is it a bug? this is a valid solution?

More information can be found at:
http://jakarta.apache.org/tomcat/tomcat-4.1-doc/class-loader-howto.html

Hi, Piero.
--------------------------------------
Dott. Pier Francesco Sormani
Synapsis S.r.l.
     in Computer Science

P.zza Dante, 19/20
57121 Livorno
Phone: +39 0586 426790
fax: +39 0586 443954
www.websynapsis.com
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