diff --git a/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockOverriddenDataTreeCodec.java b/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockOverriddenDataTreeCodec.java
new file mode 100644
index 0000000..73fddbf
--- /dev/null
+++ b/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockOverriddenDataTreeCodec.java
@@ -0,0 +1,68 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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 org.onosproject.yms.app.ymsm;
+
+import org.onosproject.yms.app.ych.YchException;
+import org.onosproject.yms.ych.YangCompositeEncoding;
+import org.onosproject.yms.ych.YangDataTreeCodec;
+import org.onosproject.yms.ydt.YdtBuilder;
+import org.onosproject.yms.ydt.YmsOperationType;
+
+/**
+ * Represents implementation of overridden YANG data tree codec interfaces.
+ */
+public class MockOverriddenDataTreeCodec implements YangDataTreeCodec {
+    private static final String PREFIX = "OverriddenDataTreeCodec ";
+    private static final String ENCODE = PREFIX +
+            "encodeYdtToProtocolFormat Called.";
+    private static final String COMPOSITE_ENCODE = PREFIX +
+            "encodeYdtToCompositeProtocolFormat Called.";
+    private static final String DECODE = PREFIX +
+            "decodeProtocolDataToYdt Called.";
+    private static final String COMPOSITE_DECODE = PREFIX +
+            "decodeCompositeProtocolDataToYdt Called.";
+
+    @Override
+    public String encodeYdtToProtocolFormat(YdtBuilder ydtBuilder) {
+
+        throw new YchException(ENCODE);
+    }
+
+    @Override
+    public YangCompositeEncoding encodeYdtToCompositeProtocolFormat(
+            YdtBuilder ydtBuilder) {
+
+        throw new YchException(COMPOSITE_ENCODE);
+    }
+
+    @Override
+    public YdtBuilder decodeProtocolDataToYdt(String protocolData,
+                                              Object schemaRegistryForYdt,
+                                              YmsOperationType proOper) {
+
+        throw new YchException(DECODE);
+    }
+
+    @Override
+    public YdtBuilder decodeCompositeProtocolDataToYdt(
+            YangCompositeEncoding protocolData,
+            Object schemaRegistryForYdt,
+            YmsOperationType proOper) {
+
+        throw new YchException(COMPOSITE_DECODE);
+    }
+}