diff --git a/runtime/Java/src/org/antlr/v4/runtime/tree/ParseTree.java b/runtime/Java/src/org/antlr/v4/runtime/tree/ParseTree.java
index d30758244..fcd10ef16 100644
--- a/runtime/Java/src/org/antlr/v4/runtime/tree/ParseTree.java
+++ b/runtime/Java/src/org/antlr/v4/runtime/tree/ParseTree.java
@@ -80,7 +80,9 @@ public interface ParseTree extends SyntaxTree {
 		public int getChildCount() { return 0; }
 
 		@Override
-		public <T> T accept(ParseTreeVisitor<? extends T> visitor) { return null; }
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			return visitor.visitTerminal(this);
+		}
 
 		@Override
 		public String toStringTree(Parser parser) {
@@ -117,6 +119,11 @@ public interface ParseTree extends SyntaxTree {
 		public ErrorNodeImpl(Symbol token) {
 			super(token);
 		}
+
+		@Override
+		public <T> T accept(ParseTreeVisitor<? extends T> visitor) {
+			return visitor.visitErrorNode(this);
+		}
 	}
 
 	// the following methods narrow the return type; they are not additional methods