Hi,
Am 25.04.2013 03:29, schrieb William Karl Thompson:
Hello,
(My apologies, I mistakenly sent this to the dev list initially)
I'm very interested in using the TextMarker project, but the current set of
action types doesn't quite do what I need. I found references to an extension
mechanism, have also found the ITextMarkerActionExtension interface in the
source code. I also found the antlr grammar and lexer files where the
TextMarker language is defined, which appears to be where new action type names
are to be added. So I surmise the steps to add new actions is to
1. Add the desired action signature to the antlr grammar
2. Define an implementation of ITextMarkerActionExtension that implements
the functionality.
Is there an easier way to do this? My concern is that I need to modify
TextMarker source files (the grammar and lexer files), which would be
overwritten on any updated version of TextMarker.
This should be possible without changing any textmarker code.
There is a generic parsing rule in the grammar, which creates an
external action using the set of ITextMarkerExtension mentioned in the
descriptor (parameter: additionalExtensions). There is no default syntax
check since the possible arguments are of course not yet known by the
engine. Syntax checks need to be implemented in the
ITextMarkerActionExtension.createAction(), which throws an
ANTLRException. The arguments of the action are delegated to this
method, which return the action implementation, so there will probably
many casts and "if instanceOf" checks. Language constructs like
assignments ("feature" = Type) known by the CREATE action, are not yet
supported.
Unfortunately, there is no automatic integration in the workbench yet.
You have to modify the BasicEngine (add the extension) in the textmarker
project yourself. The implemenatation of the extension needs of course
then also be available to the workbench.
I haven't used the language extensions since 2009 (it was a wordnet
integration) and they are not yet covered by unit tests. So, there are
maybe some bugs due to the changes after the contribution to Apache
UIMA. However, I will check the functionality, add a test case and
extend the documentation.
Concerning the list of available actions: You are of course also welcome
to create feature requests for new actions. The current set of actions
is mainly based on my own requirements and I will gladly add new
reasonable/generic actions (within the limits of my available time).
Best,
Peter
Thanks!
Will Thompson
