diff --git a/runtime/Java/src/org/antlr/v4/runtime/Parser.java b/runtime/Java/src/org/antlr/v4/runtime/Parser.java
index 839ab62c3..7b0f200cb 100644
--- a/runtime/Java/src/org/antlr/v4/runtime/Parser.java
+++ b/runtime/Java/src/org/antlr/v4/runtime/Parser.java
@@ -92,7 +92,7 @@ public abstract class Parser extends Recognizer<Token, ParserATNSimulator<Token>
 	 */
 	protected ParserRuleContext<Token> _ctx;
 
-	protected boolean _buildParseTrees;
+	protected boolean _buildParseTrees = true;
 
 	protected TraceListener _tracer;