From 1cc7ac3410dbd959f7cd03a660b5cf3bdb532f0a Mon Sep 17 00:00:00 2001
From: Terence Parr <parrt@antlr.org>
Date: Mon, 30 Jan 2012 16:51:55 -0800
Subject: [PATCH] added -trace to TestRig. fixed code gen issue for trace
 listener

---
 .../src/org/antlr/v4/runtime/misc/TestRig.java   | 16 ++++++++++++++--
 .../v4/tool/templates/codegen/Java/Java.stg      |  4 ++--
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/runtime/Java/src/org/antlr/v4/runtime/misc/TestRig.java b/runtime/Java/src/org/antlr/v4/runtime/misc/TestRig.java
index c5c747789..829d2510e 100644
--- a/runtime/Java/src/org/antlr/v4/runtime/misc/TestRig.java
+++ b/runtime/Java/src/org/antlr/v4/runtime/misc/TestRig.java
@@ -41,7 +41,11 @@ import java.lang.reflect.Method;
 /** Run a lexer/parser combo, optionally printing tree string or generating
  *  postscript file. Optionally taking input file.
  *
- *  $ java org.antlr.v4.runtime.misc.TestRig GrammarName startRuleName [-print] [-tokens] [-gui] [-ps file.ps] [input-filename]
+ *  $ java org.antlr.v4.runtime.misc.TestRig GrammarName startRuleName
+ *        [-print]
+ *        [-tokens] [-gui] [-ps file.ps]
+ *        [-trace]
+ *        [input-filename]
  */
 public class TestRig {
 	public static void main(String[] args) throws Exception {
@@ -52,9 +56,12 @@ public class TestRig {
 		boolean gui = false;
 		String psFile = null;
 		boolean showTokens = false;
+		boolean trace = false;
 		String encoding = null;
 		if ( args.length < 2 ) {
-			System.err.println("java org.antlr.v4.runtime.misc.TestRig GrammarName startRuleName [-print] [-tokens] [-gui] [-encoding encodingname] [-ps file.ps] [input-filename]");
+			System.err.println("java org.antlr.v4.runtime.misc.TestRig GrammarName startRuleName" +
+							   " [-print] [-tokens] [-gui] [-encoding encodingname]" +
+							   " [-ps file.ps] [-trace] [input-filename]");
 			return;
 		}
 		int i=0;
@@ -78,6 +85,9 @@ public class TestRig {
 			if ( arg.equals("-tokens") ) {
 				showTokens = true;
 			}
+			else if ( arg.equals("-trace") ) {
+				trace = true;
+			}
 			else if ( arg.equals("-encoding") ) {
 				if ( i>=args.length ) {
 					System.err.println("missing encoding on -encoding");
@@ -143,6 +153,8 @@ public class TestRig {
 				parser.setBuildParseTree(true);
 			}
 
+			parser.setTrace(trace);
+
 			Method startRule = parserClass.getMethod(startRuleName, (Class[])null);
 			ParserRuleContext<Token> tree = (ParserRuleContext<Token>)startRule.invoke(parser, (Object[])null);
 
diff --git a/tool/resources/org/antlr/v4/tool/templates/codegen/Java/Java.stg b/tool/resources/org/antlr/v4/tool/templates/codegen/Java/Java.stg
index 1246282a2..2be14e565 100644
--- a/tool/resources/org/antlr/v4/tool/templates/codegen/Java/Java.stg
+++ b/tool/resources/org/antlr/v4/tool/templates/codegen/Java/Java.stg
@@ -538,7 +538,7 @@ public static class <s.label>Context extends <currentRule.name>Context {
 VisitorDispatchMethod(method) ::= <<
 @Override
 public void <if(method.isEnter)>enter<else>exit<endif>Rule(ParseTreeListener\<<InputSymbolType()>\> listener) {
-	if ( listener!=null ) ((<parser.grammarName>Listener)listener).<if(method.isEnter)>enter<else>exit<endif>Rule(this);
+	if ( listener!=null && listener instanceof <parser.grammarName>Listener ) ((<parser.grammarName>Listener)listener).<if(method.isEnter)>enter<else>exit<endif>Rule(this);
 }
 >>
 
@@ -547,7 +547,7 @@ AttributeDecl(d) ::= "<d.decl>"
 /** If we don't know location of label def x, use this template */
 labelref(x) ::= "<if(!x.isLocal)>_localctx.<endif><x.name>"
 
-// used for left-recursive rules 
+// used for left-recursive rules
 recRuleDefArg()						  ::= "int _p"
 recRuleArg()						  ::= "$_p"
 recRuleAltPredicate(ruleName,opPrec)  ::= "<opPrec> >= <recRuleArg()>"