diff --git a/hdfs/CHANGES.txt b/hdfs/CHANGES.txt
index bb763934f0..c98f722051 100644
--- a/hdfs/CHANGES.txt
+++ b/hdfs/CHANGES.txt
@@ -534,7 +534,7 @@ Trunk (unreleased changes)
 
     HDFS-2110. StreamFile and ByteRangeInputStream cleanup. (eli)
 
-    HDFS-2106. Move block management code from o.a.h.h.s.namenode to a new
+    HDFS-2107. Move block management code from o.a.h.h.s.namenode to a new
     package o.a.h.h.s.blockmanagement.  (szetszwo)
 
   OPTIMIZATIONS
diff --git a/hdfs/src/java/org/apache/hadoop/hdfs/server/blockmanagement/NumberReplicas.java b/hdfs/src/java/org/apache/hadoop/hdfs/server/blockmanagement/NumberReplicas.java
new file mode 100644
index 0000000000..52f62587b1
--- /dev/null
+++ b/hdfs/src/java/org/apache/hadoop/hdfs/server/blockmanagement/NumberReplicas.java
@@ -0,0 +1,57 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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 org.apache.hadoop.hdfs.server.blockmanagement;
+
+/**
+ * A immutable object that stores the number of live replicas and
+ * the number of decommissined Replicas.
+ */
+public class NumberReplicas {
+  private int liveReplicas;
+  private int decommissionedReplicas;
+  private int corruptReplicas;
+  private int excessReplicas;
+
+  NumberReplicas() {
+    initialize(0, 0, 0, 0);
+  }
+
+  NumberReplicas(int live, int decommissioned, int corrupt, int excess) {
+    initialize(live, decommissioned, corrupt, excess);
+  }
+
+  void initialize(int live, int decommissioned, int corrupt, int excess) {
+    liveReplicas = live;
+    decommissionedReplicas = decommissioned;
+    corruptReplicas = corrupt;
+    excessReplicas = excess;
+  }
+
+  public int liveReplicas() {
+    return liveReplicas;
+  }
+  public int decommissionedReplicas() {
+    return decommissionedReplicas;
+  }
+  public int corruptReplicas() {
+    return corruptReplicas;
+  }
+  public int excessReplicas() {
+    return excessReplicas;
+  }
+}