diff --git a/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockCoreService.java b/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockCoreService.java
new file mode 100644
index 0000000..62f00aa
--- /dev/null
+++ b/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockCoreService.java
@@ -0,0 +1,73 @@
+/*
+ * 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.core.ApplicationId;
+import org.onosproject.core.CoreService;
+import org.onosproject.core.IdGenerator;
+import org.onosproject.core.Version;
+
+import java.util.Set;
+import java.util.concurrent.atomic.AtomicLong;
+
+/**
+ * Represents implementation of CoreService interfaces.
+ */
+public class MockCoreService implements CoreService {
+    @Override
+    public Version version() {
+        return null;
+    }
+
+    @Override
+    public Set<ApplicationId> getAppIds() {
+        return null;
+    }
+
+    @Override
+    public ApplicationId getAppId(Short id) {
+        return null;
+    }
+
+    @Override
+    public ApplicationId getAppId(String name) {
+        return null;
+    }
+
+    @Override
+    public ApplicationId registerApplication(String name) {
+        return null;
+    }
+
+    @Override
+    public ApplicationId registerApplication(String name,
+                                             Runnable preDeactivate) {
+        return null;
+    }
+
+    @Override
+    public IdGenerator getIdGenerator(String topic) {
+        return new IdGenerator() {
+            private AtomicLong counter = new AtomicLong(0);
+
+            @Override
+            public long getNewId() {
+                return counter.getAndIncrement();
+            }
+        };
+    }
+}
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);
+    }
+}
diff --git a/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockRegisteredDataTreeCodec.java b/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockRegisteredDataTreeCodec.java
new file mode 100644
index 0000000..84117e7
--- /dev/null
+++ b/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockRegisteredDataTreeCodec.java
@@ -0,0 +1,67 @@
+/*
+ * 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 YANG SBI broker interfaces.
+ */
+public class MockRegisteredDataTreeCodec implements YangDataTreeCodec {
+    private static final String PREFIX = "RegisteredDataTreeCodec ";
+    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 schemaRegistry,
+                                              YmsOperationType proOper) {
+
+        throw new YchException(DECODE);
+    }
+
+    @Override
+    public YdtBuilder decodeCompositeProtocolDataToYdt(
+            YangCompositeEncoding protocolData,
+            Object schemaRegistry,
+            YmsOperationType proOper) {
+
+        throw new YchException(COMPOSITE_DECODE);
+    }
+}
diff --git a/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockYangCompositeEncoding.java b/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockYangCompositeEncoding.java
new file mode 100644
index 0000000..1f52da6
--- /dev/null
+++ b/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/MockYangCompositeEncoding.java
@@ -0,0 +1,82 @@
+/*
+ * 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.ych.YangCompositeEncoding;
+import org.onosproject.yms.ych.YangResourceIdentifierType;
+
+/**
+ * Represents implementation of YangCompositeEncoding interfaces.
+ */
+public class MockYangCompositeEncoding implements YangCompositeEncoding {
+    /**
+     * Resource identifier for composite encoding.
+     */
+    private String resourceIdentifier;
+
+    /**
+     * Resource information for composite encoding.
+     */
+    private String resourceInformation;
+
+    /**
+     * Resource identifier type.
+     */
+    private YangResourceIdentifierType resourceIdentifierType;
+
+    /**
+     * Sets resource identifier.
+     *
+     * @param resIdentifier resource identifier
+     */
+    public void setResourceIdentifier(String resIdentifier) {
+        resourceIdentifier = resIdentifier;
+    }
+
+    /**
+     * Sets the resource information.
+     *
+     * @param resInformation resource information
+     */
+    public void setResourceInformation(String resInformation) {
+        resourceInformation = resInformation;
+    }
+
+    /**
+     * Sets the resource identifier type.
+     *
+     * @param resIdent resource identifier
+     */
+    public void setResourceIdentifierType(YangResourceIdentifierType resIdent) {
+        resourceIdentifierType = resIdent;
+    }
+
+    @Override
+    public String getResourceIdentifier() {
+        return resourceIdentifier;
+    }
+
+    @Override
+    public YangResourceIdentifierType getResourceIdentifierType() {
+        return resourceIdentifierType;
+    }
+
+    @Override
+    public String getResourceInformation() {
+        return resourceInformation;
+    }
+}
diff --git a/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/YchCompositeHandlerTest.java b/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/YchCompositeHandlerTest.java
new file mode 100644
index 0000000..794298e
--- /dev/null
+++ b/apps/yms/app/src/test/java/org/onosproject/yms/app/ymsm/YchCompositeHandlerTest.java
@@ -0,0 +1,288 @@
+/*
+ * 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.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.onosproject.yang.gen.v1.ydt.customs.supervisor.rev20160524.CustomssupervisorOpParam;
+import org.onosproject.yms.app.ych.defaultcodecs.YangCodecRegistry;
+import org.onosproject.yms.app.ysr.TestYangSchemaNodeProvider;
+import org.onosproject.yms.ych.YangCodecHandler;
+import org.onosproject.yms.ych.YangCompositeEncoding;
+import org.onosproject.yms.ych.YangDataTreeCodec;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import static junit.framework.TestCase.assertNotNull;
+import static org.onosproject.yms.ych.YangProtocolEncodingFormat.XML;
+
+/**
+ * Unit test case for YCH composite codec handler.
+ */
+public class YchCompositeHandlerTest {
+    @Rule
+    public ExpectedException thrown = ExpectedException.none();
+
+    private static final String REG_PREFIX = "RegisteredDataTreeCodec ";
+    private static final String REG_ENCODE = REG_PREFIX +
+            "encodeYdtToProtocolFormat Called.";
+    private static final String REG_DECODE = REG_PREFIX +
+            "decodeProtocolDataToYdt Called.";
+    private static final String REG_COMPO_ENCODE = REG_PREFIX +
+            "encodeYdtToCompositeProtocolFormat Called.";
+    private static final String REG_COMPO_DECODE = REG_PREFIX +
+            "decodeCompositeProtocolDataToYdt Called.";
+    private static final String OVERRIDE_PREFIX = "OverriddenDataTreeCodec ";
+    private static final String OVERRIDE_ENCODE = OVERRIDE_PREFIX +
+            "encodeYdtToProtocolFormat Called.";
+    private static final String OVERRIDE_DECODE = OVERRIDE_PREFIX +
+            "decodeProtocolDataToYdt Called.";
+    private static final String OVERRIDE_COMPO_ENCODE = OVERRIDE_PREFIX +
+            "encodeYdtToCompositeProtocolFormat Called.";
+    private static final String OVERRIDE_COMPO_DECODE = OVERRIDE_PREFIX +
+            "decodeCompositeProtocolDataToYdt Called.";
+
+    private TestYangSchemaNodeProvider provider =
+            new TestYangSchemaNodeProvider();
+
+    /**
+     * Unit test case in which verifying codec handler is null or not.
+     */
+    @Test
+    public void checkForCodecHandler() {
+        YmsManager ymsManager = new YmsManager();
+        ymsManager.coreService = new MockCoreService();
+        ymsManager.activate();
+        YangCodecHandler yangCodecHandler = ymsManager.getYangCodecHandler();
+        assertNotNull("Codec handler is null", yangCodecHandler);
+    }
+
+    /**
+     * Unit test case in which verifying registered codec handler for encode is
+     * null or not.
+     */
+    @Test
+    public void checkForRegisterDefaultCodecEncode() {
+        thrown.expectMessage(REG_ENCODE);
+        YangDataTreeCodec yangDataTreeCodec = new MockRegisteredDataTreeCodec();
+        YmsManager ymsManager = new YmsManager();
+        YangCodecRegistry.initializeDefaultCodec();
+        ymsManager.coreService = new MockCoreService();
+        ymsManager.activate();
+        ymsManager.registerDefaultCodec(yangDataTreeCodec, XML);
+        YangCodecHandler yangCodecHandler = ymsManager.getYangCodecHandler();
+        assertNotNull("Codec handler is null", yangCodecHandler);
+
+        provider.processSchemaRegistry(null);
+        List<Object> yangModuleList = new ArrayList<>();
+
+        // Creating the object
+        Object object = CustomssupervisorOpParam.builder()
+                .supervisor("Customssupervisor").build();
+        yangModuleList.add(object);
+
+        // Get the xml string and compare
+        Map<String, String> tagAttr = new HashMap<String, String>();
+        tagAttr.put("type", "subtree");
+
+        yangCodecHandler.encodeOperation("filter", "ydt.filter-type",
+                                         tagAttr, yangModuleList,
+                                         XML, null);
+    }
+
+    /**
+     * Unit test case in which verifying registered codec handler for decode is
+     * null or not.
+     */
+    @Test
+    public void checkForRegisterDefaultCodecDecode() {
+        thrown.expectMessage(REG_DECODE);
+        YangDataTreeCodec yangDataTreeCodec = new MockRegisteredDataTreeCodec();
+        YmsManager ymsManager = new YmsManager();
+        YangCodecRegistry.initializeDefaultCodec();
+        ymsManager.coreService = new MockCoreService();
+        ymsManager.activate();
+        ymsManager.registerDefaultCodec(yangDataTreeCodec, XML);
+        YangCodecHandler yangCodecHandler = ymsManager.getYangCodecHandler();
+        assertNotNull("Codec handler is null", yangCodecHandler);
+
+        provider.processSchemaRegistry(null);
+        yangCodecHandler.decode("XML String", XML, null);
+    }
+
+    /**
+     * Unit test case in which verifying registered codec handler for
+     * composite encode is null or not.
+     */
+    @Test
+    public void checkForRegisterDefaultCodecCompEncode() {
+        thrown.expectMessage(REG_COMPO_ENCODE);
+        YangDataTreeCodec yangDataTreeCodec = new MockRegisteredDataTreeCodec();
+        YmsManager ymsManager = new YmsManager();
+        YangCodecRegistry.initializeDefaultCodec();
+        ymsManager.coreService = new MockCoreService();
+        ymsManager.activate();
+        ymsManager.registerDefaultCodec(yangDataTreeCodec, XML);
+        YangCodecHandler yangCodecHandler = ymsManager.getYangCodecHandler();
+        assertNotNull("Codec handler is null", yangCodecHandler);
+
+        provider.processSchemaRegistry(null);
+        // Creating the object
+        Object object = CustomssupervisorOpParam.builder()
+                .supervisor("Customssupervisor").build();
+
+        yangCodecHandler.encodeCompositeOperation("filter",
+                                                  "ydt.filter-type", object,
+                                                  XML, null);
+    }
+
+    /**
+     * Unit test case in which verifying registered codec handler for
+     * composite decode is null or not.
+     */
+    @Test
+    public void checkForRegisterDefaultCodecCompDecode() {
+        thrown.expectMessage(REG_COMPO_DECODE);
+        YangDataTreeCodec yangDataTreeCodec = new MockRegisteredDataTreeCodec();
+        YmsManager ymsManager = new YmsManager();
+        YangCodecRegistry.initializeDefaultCodec();
+        ymsManager.coreService = new MockCoreService();
+        ymsManager.activate();
+        ymsManager.registerDefaultCodec(yangDataTreeCodec, XML);
+        YangCodecHandler yangCodecHandler = ymsManager.getYangCodecHandler();
+        assertNotNull("Codec handler is null", yangCodecHandler);
+
+        provider.processSchemaRegistry(null);
+        // Creating the object
+        YangCompositeEncoding yangCompositeEncoding =
+                new MockYangCompositeEncoding();
+        yangCodecHandler.decode(yangCompositeEncoding, XML, null);
+    }
+
+    /**
+     * Unit test case in which verifying overridden codec handler for encode is
+     * null or not.
+     */
+    @Test
+    public void checkForOverriddenDataTreeCodecEncode() {
+        thrown.expectMessage(OVERRIDE_ENCODE);
+        YangDataTreeCodec yangDataTreeCodec = new MockRegisteredDataTreeCodec();
+        YmsManager ymsManager = new YmsManager();
+        ymsManager.coreService = new MockCoreService();
+        ymsManager.activate();
+        ymsManager.registerDefaultCodec(yangDataTreeCodec, XML);
+        YangCodecHandler yangCodecHandler = ymsManager.getYangCodecHandler();
+        assertNotNull("Codec handler is null", yangCodecHandler);
+
+        YangDataTreeCodec overriddenCodec = new MockOverriddenDataTreeCodec();
+        yangCodecHandler.registerOverriddenCodec(overriddenCodec, XML);
+
+        provider.processSchemaRegistry(null);
+        List<Object> yangModuleList = new ArrayList<>();
+
+        // Creating the object
+        Object object = CustomssupervisorOpParam.builder()
+                .supervisor("Customssupervisor").build();
+        yangModuleList.add(object);
+
+        // Get the xml string and compare
+        Map<String, String> tagAttr = new HashMap<String, String>();
+        tagAttr.put("type", "subtree");
+        yangCodecHandler.encodeOperation("filter", "ydt.filter-type",
+                                         tagAttr, yangModuleList,
+                                         XML, null);
+    }
+
+    /**
+     * Unit test case in which verifying overridden codec handler for decode is
+     * null or not.
+     */
+    @Test
+    public void checkForOverriddenDataTreeCodecDecode() {
+        thrown.expectMessage(OVERRIDE_DECODE);
+        YangDataTreeCodec yangDataTreeCodec = new MockRegisteredDataTreeCodec();
+        YmsManager ymsManager = new YmsManager();
+        ymsManager.coreService = new MockCoreService();
+        ymsManager.activate();
+        ymsManager.registerDefaultCodec(yangDataTreeCodec, XML);
+        YangCodecHandler yangCodecHandler = ymsManager.getYangCodecHandler();
+        assertNotNull("Codec handler is null", yangCodecHandler);
+
+        YangDataTreeCodec overriddenCodec = new MockOverriddenDataTreeCodec();
+        yangCodecHandler.registerOverriddenCodec(overriddenCodec, XML);
+
+        provider.processSchemaRegistry(null);
+        yangCodecHandler.decode("XML String", XML, null);
+    }
+
+    /**
+     * Unit test case in which verifying overridden codec handler for
+     * composite encode is null or not.
+     */
+    @Test
+    public void checkForOverriddenDataTreeCodecCompoEncode() {
+        thrown.expectMessage(OVERRIDE_COMPO_ENCODE);
+        YangDataTreeCodec yangDataTreeCodec = new MockRegisteredDataTreeCodec();
+        YmsManager ymsManager = new YmsManager();
+        ymsManager.coreService = new MockCoreService();
+        ymsManager.activate();
+        ymsManager.registerDefaultCodec(yangDataTreeCodec, XML);
+        YangCodecHandler yangCodecHandler = ymsManager.getYangCodecHandler();
+        assertNotNull("Codec handler is null", yangCodecHandler);
+
+        YangDataTreeCodec overriddenCodec = new MockOverriddenDataTreeCodec();
+        yangCodecHandler.registerOverriddenCodec(overriddenCodec, XML);
+
+        provider.processSchemaRegistry(null);
+        // Creating the object
+        Object object = CustomssupervisorOpParam.builder()
+                .supervisor("Customssupervisor").build();
+        yangCodecHandler.encodeCompositeOperation("filter",
+                                                  "ydt.filter-type",
+                                                  object,
+                                                  XML, null);
+    }
+
+    /**
+     * Unit test case in which verifying overridden codec handler for
+     * composite decode is null or not.
+     */
+    @Test
+    public void checkForOverriddenDataTreeCodecCompoDecode() {
+        thrown.expectMessage(OVERRIDE_COMPO_DECODE);
+        YangDataTreeCodec yangDataTreeCodec = new MockRegisteredDataTreeCodec();
+        YmsManager ymsManager = new YmsManager();
+        ymsManager.coreService = new MockCoreService();
+        ymsManager.activate();
+        ymsManager.registerDefaultCodec(yangDataTreeCodec, XML);
+        YangCodecHandler yangCodecHandler = ymsManager.getYangCodecHandler();
+        assertNotNull("Codec handler is null", yangCodecHandler);
+
+        YangDataTreeCodec overriddenCodec = new MockOverriddenDataTreeCodec();
+        yangCodecHandler.registerOverriddenCodec(overriddenCodec, XML);
+
+        provider.processSchemaRegistry(null);
+        // Verify the received object list
+        YangCompositeEncoding yangCompositeEncoding =
+                new MockYangCompositeEncoding();
+        yangCodecHandler.decode(yangCompositeEncoding, XML, null);
+    }
+}