Quick overview
Please refer to the instructions on the grappa-tracer-backport project.
Recall: you need at least Oracle JRE 1.8u25.
When you have downloaded the "binary jar", launch it by either double clicking on it (if your OS has linked jar files to your Java executable) or, at the command line:
# x.y.z is the version you are using
$ java -jar grappa-debugger-x.y.z-lib.jarYou will be greeted with this window:
As the initial window instructs, use the File menu then Load file menu entry to load your trace file.
When you have opened the trace file, the debugger will create a H2 database and inject the data from your trace file in it. If the load is not complete yet, the application is still usable, and you have the option to refresh the statistics:
The parse tree tab, which is the leftmost tab, will only display the tree once the load is complete:
It is collapsed at first; you can expand the parts you want (note that nodes are loaded lazily), and when you select a node, information will appear on the lower left part while the right part will be updated to show three zones of text:
- the text already processed at that point (appears gray);
- the text matched by the rule, if the rule matches, surrounded by arrows;
- the text not yet processed at that point.
Note that the text will automatically scroll to the matched point; also, if the match is empty, an empty set character will appear instead, and if the match fails, a ballot box will appear instead.
The second tab contains statistics about the rules: how many rules have been recorded, their class, their type (actions, predicates, composite matchers or terminal matchers), plus general information about the parsing process.
Example:
The third tab contains statistics about the matches themselves: success rates, empty matches, non empty matches, and the total number of nodes in the parse tree:
Finally, the fourth and last screen contains a graph which shows the depth of the parse tree by line. Only the matchers which were active for this line are considered:
You have the option to display either 10, 25 or 50 lines at a time.
Until the next version!