[UIMA-4517] fixing ArrayOutOfBounds exception when parsing invalid Ruta script

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.3.1ruta
• Fix Version/s: 2.3.1ruta
• Component/s: Ruta
• Assignee: Peter Klügl
• Reporter: Renaud Richardet
• Created: 17/Jul/15 18:59
• Updated: 09/Aug/15 18:25
• Resolved: 09/Aug/15 18:25

Description

looking for more informative exception messages when parsing invalid Ruta script

When using Ruta in a non-Workbench setup (in my case, Maven), I don't manage to catch Ruta script errors in a meaningful way. Here is an example:

"aaa\." -> MyAnnotation; // fails because of escaped dot

The thrown error is quite uninformative:

java.lang.ArrayIndexOutOfBoundsException: -1
at org.apache.uima.ruta.parser.RutaParser.emitErrorMessage(RutaParser.java:365)
at org.apache.uima.ruta.parser.RutaParser.reportError(RutaParser.java:386)
at org.antlr.runtime.BaseRecognizer.recoverFromMismatchedToken(BaseRecognizer.java:603)
at org.antlr.runtime.BaseRecognizer.match(BaseRecognizer.java:115)
at org.apache.uima.ruta.parser.RutaParser.file_input(RutaParser.java:680)
at org.apache.uima.ruta.engine.RutaEngine.loadScript(RutaEngine.java:1058)
at org.apache.uima.ruta.engine.RutaEngine.initializeScript(RutaEngine.java:743)
...

Here is the code to reproduce: https://github.com/renaud/annotate_ruta_example/tree/ruta_error_message

However, if I paste that script line in the Ruta Workbench, it nicely underlines it in red at the exact location, and even says "Mismatched input". How do I achieve the same programatically (from Java)?