Getting the name of the currently executing rule

[Dov Rosenberg]

how do I get the name of the currently executing rule while using a listener? I found the enterEveryRule() but I dont see anything that provides the name of the rule that is executing like the -trace option on the TestRig

Thanks in advance

Dov Rosenberg

[Norman Dunbar]

Hi Dov,

This works:

In the java file for the listener:

public class tns2toadListener extends tnsnamesBaseListener
{
tnsnamesParser parser; // The Parser we are listening for.
String[] ruleNames; // The parser's list of rule names.
...

In the constructor for the listener, we need the parser as a parameter:

public tns2toadListener(tnsnamesParser parser, ....)
{
this.parser = parser;
this.ruleNames = parser.getRuleNames();
...

In the EveryRule listener method, we do this:

@Override
public void enterEveryRule(ParserRuleContext ctx)
{
String Rule = this.ruleNames[ctx.getRuleIndex()];
System.out.println("Rule = " + Rule);
...

The Rule string should contain the rule that is currently executing.

In the java file for the app itself, we have this:

ANTLRInputStream input = new ANTLRInputStream(iStream);
tnsnamesLexer lexer = new tnsnamesLexer(input);

CommonTokenStream tokens = new CommonTokenStream(lexer);
tnsnamesParser parser = new tnsnamesParser(tokens);
ParseTree tree = parser.tnsnames();

ParseTreeWalker tnsWalker = new ParseTreeWalker();

// Create my listener and pass in the parser etc.
tns2toadListener tnsListener = new tns2toadListener(parser, ...);
tnsWalker.walk(tnsListener, tree);


When running the finished app, I get something similar to the following:

Rule = tnsnames
Rule = alias_list
Rule = alias
Rule = description
Rule = address
Rule = protocol_info
Rule = tcp_protocol
Rule = tcp_params
Rule = tcp_parameter
Rule = tcp_tcp
Rule = tcp_parameter
Rule = tcp_host
Rule = host
Rule = tcp_parameter
Rule = tcp_port
Rule = port
Rule = connect_data
Rule = cd_params
Rule = cd_parameter
Rule = cd_server
Rule = cd_parameter
Rule = cd_service_name

and so on, and on and on ... ;-)

HTH

Cheers,
Norm.

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.

[Terence Parr]

off top of my head, ask parser or interp for current ATN state. Ask the state for rule index it’s embedded in. then ask parser for name for that index.

T

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[Dov Rosenberg]

I did as Norman suggested and that worked great!!