The XPDL Validation Web Application
The XPDL Validation Web Application provides a way for members of the XPDL
community to check XPDL files against the XPDL schema. It hoped that this will
advance the development of tools that generate correct XPDL that can be exchanged
and used by tools m
y multiple vendors.
Andy Adler developed
the direction of Robert Shapiro. Tom
transform used by
The validator is
implemented using Java Server Pages that access the Java based
rsing and validation packages found in javax.xml, org.w3c.dom, and
The validator was developed using version 6.5 of the open source development
, which can be found at
Netbeans is available on several platforms. The bulk of the development of the
validator was done on a Macintosh running OS X 10.5.
The validator was tested
using version 6.0 of the Tomcat JSP
there should be nothing to prevent using a different container
The Netbeans project generates
a hierarchy that is rooted in
…/XPDLValidator/build/web. This file
a WAR archive.
Most hosts using Tomcat use the WAR, but the public test site uses the raw file
Deploying to XPDL.org
An XPDL user can find the validator on the XPDL.org web site at
. Currently, no attempt has been made to fit the validator
web pages are into the look and feel of this site.
are copied to the XPDL.org host by using FTP.
Connect using host
as the user name.
The password is
Once connected, change the working directory to
above, this host does not use WAR archives, so to deploy the validator copy
all the files and directories, excluding the CVS
directory, from the
directory on your development host.
Note: The built site and its archive are saved
under source control so that the validator can be deployed by someone who does
not have a development environment.
Tomcat loads the applicati
on on start up. So, Tomcat needs to be cycled to tell it to
load a new version. Access to Tomcat is through the
control panel provided by the
hosting company, Moca
log in u
same username and password mentioned above. Ignore the icon in the Software /
Services section labeled Tomcat Restart. I am told that it does not do the correct
scroll to the bottom of the page where you will find a section labe
Advanced. Click on the icon for NGASI
Manager and you will see a new
On this control page, titled Java Automation and Load
Balancing for Cloud
Computing, you will see stack of tabs on the left.
Click on the Start / Stop ta
be the second tab. You will now see three buttons across the top Start, Stop,
and Restart. Once again, ignore the Restart button and instead press Stop. It takes a
bit for this to complete and you will be entertained by a progress dialog b
the server is off, turn it back on by pressing Start.
This action also takes a bit to
complete. Once the progress dialog disappears, the new version of the validator
should be ready to use.
The validator web application consists of two
pages: an introductory page that
documents some details about preparing an XPDL file for validator and the validator
page. The validator page is divided into two sections. The top area is a form used to
upload the XPDL file and to specify what changes, i
f any, the validator should apply
to XPPD file before it is validated.
The bottom area is used to display the results of
the validator’s work.
The validator applies two tests to the XPDL file. First, the file is validated against the
ecks for compliance to the schemata such as missing or
. Second, a diagnostic transform is applied to the XPDL file.
reports on more subtle errors. For example it notices when a connector’s end node
section describes the files that together make the validator.
This is the introductory page that explains how the validator works. This page links
, the validator page itself
This is the style shee
t used to style all the html displayed by the Validation Web
Application. When the web application is incorporated into another web site, for
example the WfMC web site, the application will need to fit in to the containing site
and these s
yles will need
to be updated or removed
and the styles in the html will
have to be changed
ValidateXPDL implements the servlet that presents the user interface of the
validator. It extends HttpServlet and has two displa
y states. The top of the page
contains a form that lets the user specify the file to be validated and what if any
changes to the file the validator should make. Since the validator takes its cue from
the XPDL file, the values of
the namespace declaration
s on the Package element and
the content of the ConformanceClass element are set from the values in the form.
DomDocument wraps a document represented by org.w3c.dom.Document and
provides easy access to functions that parse, access elements, insert elements, and
extends DomDocument to provide an easy way to examine and
change the XPDL element attributes and values required by the validation process.