1 files changed, 10 insertions, 31 deletions

diff --git a/tool/src/org/antlr/v4/misc/Graph.java b/tool/src/org/antlr/v4/misc/Graph.java
index a7c63d5..ec4c147 100644
--- a/tool/src/org/antlr/v4/misc/Graph.java
+++ b/tool/src/org/antlr/v4/misc/Graph.java
@@ -1,37 +1,14 @@
 /*
- * [The "BSD license"]
- *  Copyright (c) 2012 Terence Parr
- *  Copyright (c) 2012 Sam Harwell
- *  All rights reserved.
- *
- *  Redistribution and use in source and binary forms, with or without
- *  modification, are permitted provided that the following conditions
- *  are met:
- *
- *  1. Redistributions of source code must retain the above copyright
- *     notice, this list of conditions and the following disclaimer.
- *  2. Redistributions in binary form must reproduce the above copyright
- *     notice, this list of conditions and the following disclaimer in the
- *     documentation and/or other materials provided with the distribution.
- *  3. The name of the author may not be used to endorse or promote products
- *     derived from this software without specific prior written permission.
- *
- *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- *  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * Copyright (c) 2012-2016 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
  */
 package org.antlr.v4.misc;
 
 import org.antlr.v4.runtime.misc.OrderedHashSet;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -44,13 +21,15 @@ import java.util.Set;
 public class Graph<T> {
 
 	public static class Node<T> {
-		T payload;
-		List<Node<T>> edges; // points at which nodes?
+		public T payload;
+
+		@SuppressWarnings("unchecked")
+		public List<Node<T>> edges = Collections.EMPTY_LIST; // points at which nodes?
 
 		public Node(T payload) { this.payload = payload; }
 
 		public void addEdge(Node<T> n) {
-			if ( edges==null ) edges = new ArrayList<Node<T>>();
+			if ( edges==Collections.EMPTY_LIST ) edges = new ArrayList<Node<T>>();
 			if ( !edges.contains(n) ) edges.add(n);
 		}
 
@@ -68,7 +47,7 @@ public class Graph<T> {
 		a_node.addEdge(b_node);
 	}
 
-	protected Node<T> getNode(T a) {
+	public Node<T> getNode(T a) {
 		Node<T> existing = nodes.get(a);
 		if ( existing!=null ) return existing;
 		Node<T> n = new Node<T>(a);