Update from Google.

--
MOE_MIGRATED_REVID=85702957
diff --git a/src/main/java/com/google/devtools/build/lib/util/AbstractIndexer.java b/src/main/java/com/google/devtools/build/lib/util/AbstractIndexer.java
new file mode 100644
index 0000000..4b61fe6
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/util/AbstractIndexer.java
@@ -0,0 +1,37 @@
+// 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.
+
+package com.google.devtools.build.lib.util;
+
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+/**
+ * Abstract class for string indexers.
+ */
+abstract class AbstractIndexer implements StringIndexer {
+
+  /**
+   * Conversion from String to byte[].
+   */
+  protected static byte[] string2bytes(String string) {
+    return string.getBytes(UTF_8);
+  }
+
+  /**
+   * Conversion from byte[] to String.
+   */
+  protected static String bytes2string(byte[] bytes) {
+    return new String(bytes, UTF_8);
+  }
+}