Get rid of default values for the sonar.cxx.<reportsource>.reportPath

[wenns]

I consider those values to be of no real help, introducing them was probably a dumb idea. Also, once we have no default values anymore, we could print warnings into the log if a value is set and yields no files, which is valuable user feedback.

[guwirth]

Don't understand the problem?

[wenns]

It is a usability improvement. The plugin would be easier to use if there would be a warning in the logs in case one gets the pattern in e.g. "sonar.cxx.cppcheck.reportPath" wrong. Its not the case now, because there is a default value, for cppcheck it is:

private static final String DEFAULT_REPORT_PATH = "cppcheck-reports/cppcheck-result-*.xml";

[guwirth]

@wenns does this mean only removing the defaults or do we have to add also checks/warnings?

[wenns]

I think this task is composed of following smaller ones:

• remove the default paths, and all the code around them
• modify the shouldExecute... to let the sensor run only if the according report property is set
• add a warning if the property doesnt point to a file
• adjust the documentation accordingly, mention in the change in the upgrade nodes.

That way, we have (somewhat) smaller logs, a little bit less code, (somewhat) better running times and better usability because of the warnings.

[wenns]

By the way: this issue becomes apparent in #278 thread: if the plugin had warned about the report pointing to nothing, analysing the problem for @jfallot would have been a lot easier.