1 files changed, 31 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/graph/AbstractGraphVisitor.java b/src/main/java/com/google/devtools/build/lib/graph/AbstractGraphVisitor.java
new file mode 100644
index 0000000000..a08ed42a58
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/graph/AbstractGraphVisitor.java
@@ -0,0 +1,31 @@
+// Copyright 2014 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// All Rights Reserved.
+
+package com.google.devtools.build.lib.graph;
+
+/**
+ *  <p> A stub implementation of GraphVisitor providing default behaviour (do
+ *  nothing) for all its methods. </p>
+ */
+public class AbstractGraphVisitor<T> implements GraphVisitor<T> {
+  @Override
+  public void beginVisit() {}
+  @Override
+  public void endVisit() {}
+  @Override
+  public void visitEdge(Node<T> lhs, Node<T> rhs) {}
+  @Override
+  public void visitNode(Node<T> node) {}
+}