diff --git a/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/GroupingListenerTest.java b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/GroupingListenerTest.java
new file mode 100644
index 0000000..ec0e41c
--- /dev/null
+++ b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/GroupingListenerTest.java
@@ -0,0 +1,189 @@
+/*
+ * Copyright 2016 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.yangutils.parser.impl.listeners;
+
+import java.io.IOException;
+import java.util.ListIterator;
+import org.junit.Test;
+import org.onosproject.yangutils.datamodel.YangContainer;
+import org.onosproject.yangutils.datamodel.YangGrouping;
+import org.onosproject.yangutils.datamodel.YangLeaf;
+import org.onosproject.yangutils.datamodel.YangList;
+import org.onosproject.yangutils.datamodel.YangModule;
+import org.onosproject.yangutils.datamodel.YangNode;
+import org.onosproject.yangutils.datamodel.YangNodeType;
+import org.onosproject.yangutils.datamodel.YangStatusType;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+import org.onosproject.yangutils.parser.impl.YangUtilsParserManager;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.Is.is;
+
+/**
+ * Test cases for testing grouping listener.
+ */
+public class GroupingListenerTest {
+
+    private final YangUtilsParserManager manager = new YangUtilsParserManager();
+
+    /**
+     * Checks grouping statement inside module.
+     */
+    @Test
+    public void processGroupingInModule() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/GroupingInModule.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangGrouping yangGrouping = (YangGrouping) yangNode.getChild();
+        assertThat(yangGrouping.getName(), is("endpoint"));
+
+        ListIterator<YangLeaf> leafIterator = yangGrouping.getListOfLeaf().listIterator();
+        YangLeaf leafInfo = leafIterator.next();
+
+        assertThat(leafInfo.getLeafName(), is("address"));
+    }
+
+    /**
+     * Checks grouping statement inside container.
+     */
+    @Test
+    public void processGroupingInContainer() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/GroupingInContainer.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangContainer yangContainer = (YangContainer) yangNode.getChild();
+        assertThat(yangContainer.getName(), is("valid"));
+
+        YangGrouping yangGrouping = (YangGrouping) yangContainer.getChild();
+        assertThat(yangGrouping.getName(), is("endpoint"));
+
+        ListIterator<YangLeaf> leafIterator = yangGrouping.getListOfLeaf().listIterator();
+        YangLeaf leafInfo = leafIterator.next();
+
+        assertThat(leafInfo.getLeafName(), is("address"));
+    }
+
+    /**
+     * Checks grouping statement inside list.
+     */
+    @Test
+    public void processGroupingInList() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/GroupingInList.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangList yangList = (YangList) yangNode.getChild();
+        assertThat(yangList.getName(), is("valid"));
+
+        YangGrouping yangGrouping = (YangGrouping) yangList.getChild();
+        assertThat(yangGrouping.getName(), is("endpoint"));
+
+        ListIterator<YangLeaf> leafIterator = yangGrouping.getListOfLeaf().listIterator();
+        YangLeaf leafInfo = leafIterator.next();
+
+        assertThat(leafInfo.getLeafName(), is("address"));
+    }
+
+    /**
+     * Checks grouping with attributes.
+     */
+    @Test
+    public void processGroupingAttributes() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/GroupingAttributes.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangList yangList = (YangList) yangNode.getChild();
+        assertThat(yangList.getName(), is("valid"));
+
+        YangGrouping yangGrouping = (YangGrouping) yangList.getChild();
+        assertThat(yangGrouping.getName(), is("endpoint"));
+        assertThat(yangGrouping.getStatus(), is(YangStatusType.CURRENT));
+        assertThat(yangGrouping.getReference(), is("\"RFC 6020\""));
+        assertThat(yangGrouping.getDescription(), is("\"grouping under test\""));
+
+        ListIterator<YangLeaf> leafIterator = yangGrouping.getListOfLeaf().listIterator();
+        YangLeaf leafInfo = leafIterator.next();
+
+        assertThat(leafInfo.getLeafName(), is("address"));
+    }
+
+    /**
+     * Checks duplicate grouping in list.
+     */
+    @Test(expected = ParserException.class)
+    public void processDuplicateGroupingInList() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/DuplicateGroupingInList.yang");
+    }
+
+    /**
+     * Checks duplicate grouping in container.
+     */
+    @Test (expected = ParserException.class)
+    public void processDuplicateGroupingInContainer() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/DuplicateGroupingInContainer.yang");
+    }
+
+    /**
+     * Checks duplicate grouping in module.
+     */
+    @Test (expected = ParserException.class)
+    public void processDuplicateGroupingInModule() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/DuplicateGroupingInModule.yang");
+    }
+}
diff --git a/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/ShortCaseListenerTest.java b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/ShortCaseListenerTest.java
new file mode 100644
index 0000000..6057a7f
--- /dev/null
+++ b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/ShortCaseListenerTest.java
@@ -0,0 +1,102 @@
+/*
+ * Copyright 2014-2016 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.yangutils.parser.impl.listeners;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.Is.is;
+import org.junit.Test;
+import org.onosproject.yangutils.datamodel.YangCase;
+import org.onosproject.yangutils.datamodel.YangChoice;
+import org.onosproject.yangutils.datamodel.YangContainer;
+import org.onosproject.yangutils.datamodel.YangList;
+import org.onosproject.yangutils.datamodel.YangModule;
+import org.onosproject.yangutils.datamodel.YangNode;
+import org.onosproject.yangutils.datamodel.YangNodeType;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+import org.onosproject.yangutils.parser.impl.YangUtilsParserManager;
+
+import java.io.IOException;
+
+/**
+ * Test cases for short case listener.
+ */
+public class ShortCaseListenerTest {
+
+    private final YangUtilsParserManager manager = new YangUtilsParserManager();
+
+    /**
+     * Checks short case listener with container.
+     */
+    @Test
+    public void processShortCaseListenerWithContainer() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/ShortCaseListenerWithContainer.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangContainer yangContainer = (YangContainer) yangNode.getChild();
+        assertThat(yangContainer.getName(), is("food"));
+
+        YangChoice yangChoice = (YangChoice) yangContainer.getChild();
+        assertThat(yangChoice.getName(), is("snack"));
+
+        YangCase yangCase = (YangCase) yangChoice.getChild();
+        assertThat(yangCase.getName(), is("sports-arena"));
+
+        YangContainer yangContainer1 = (YangContainer) yangCase.getChild();
+        assertThat(yangContainer1.getName(), is("sports-arena"));
+    }
+
+    /**
+     * Checks short case listener with list.
+     */
+    @Test
+    public void processShortCaseListenerWithList() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/ShortCaseListenerWithList.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangContainer yangContainer = (YangContainer) yangNode.getChild();
+        assertThat(yangContainer.getName(), is("food"));
+
+        YangChoice yangChoice = (YangChoice) yangContainer.getChild();
+        assertThat(yangChoice.getName(), is("snack"));
+
+        YangCase yangCase = (YangCase) yangChoice.getChild();
+        assertThat(yangCase.getName(), is("sports-arena"));
+
+        YangList yangList = (YangList) yangCase.getChild();
+        assertThat(yangList.getName(), is("sports-arena"));
+    }
+}
diff --git a/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/UnionListenerTest.java b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/UnionListenerTest.java
new file mode 100644
index 0000000..4446f08
--- /dev/null
+++ b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/UnionListenerTest.java
@@ -0,0 +1,141 @@
+/*
+ * Copyright 2016 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.yangutils.parser.impl.listeners;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.ListIterator;
+import org.junit.Test;
+import org.onosproject.yangutils.datamodel.YangDataTypes;
+import org.onosproject.yangutils.datamodel.YangLeaf;
+import org.onosproject.yangutils.datamodel.YangLeafList;
+import org.onosproject.yangutils.datamodel.YangList;
+import org.onosproject.yangutils.datamodel.YangModule;
+import org.onosproject.yangutils.datamodel.YangNode;
+import org.onosproject.yangutils.datamodel.YangNodeType;
+import org.onosproject.yangutils.datamodel.YangType;
+import org.onosproject.yangutils.datamodel.YangUnion;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+import org.onosproject.yangutils.parser.impl.YangUtilsParserManager;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.Is.is;
+
+/**
+ * Test cases for testing union listener.
+ */
+public class UnionListenerTest {
+
+    private final YangUtilsParserManager manager = new YangUtilsParserManager();
+
+    /**
+     * Checks union when type is in leaf.
+     */
+    @Test
+    public void processUnionWhenTypeInLeaf() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/UnionWhenTypeInLeaf.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangList yangList = (YangList) yangNode.getChild();
+        assertThat(yangList.getName(), is("valid"));
+
+        ListIterator<YangLeaf> leafIterator = yangList.getListOfLeaf().listIterator();
+        YangLeaf leafInfo = leafIterator.next();
+
+        assertThat(leafInfo.getLeafName(), is("invalid-interval"));
+
+        assertThat(leafInfo.getDataType().getDataType(), is(YangDataTypes.UNION));
+        assertThat(leafInfo.getDataType().getDataTypeName(), is("union"));
+
+        YangUnion yangUnion = (YangUnion) leafInfo.getDataType().getDataTypeExtendedInfo();
+
+        List<YangType<?>> typeList = yangUnion.getTypeList();
+        ListIterator<YangType<?>> typeListIterator = typeList.listIterator();
+        YangType<?> yangType = typeListIterator.next();
+
+        assertThat(yangType.getDataTypeName(), is("int32"));
+        assertThat(yangType.getDataType(), is(YangDataTypes.INT32));
+
+        YangType<?> yangTypeEnum = typeListIterator.next();
+
+        assertThat(yangTypeEnum.getDataTypeName(), is("enumeration"));
+        assertThat(yangTypeEnum.getDataType(), is(YangDataTypes.ENUMERATION));
+    }
+
+    /**
+     * Checks union when type is in leaflist.
+     */
+    @Test
+    public void processUnionWhenTypeInLeafList() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/UnionWhenTypeInLeafList.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangList yangList = (YangList) yangNode.getChild();
+        assertThat(yangList.getName(), is("valid"));
+
+        ListIterator<YangLeafList> leafListIterator = yangList.getListOfLeafList().listIterator();
+        YangLeafList leafListInfo = leafListIterator.next();
+
+        assertThat(leafListInfo.getLeafName(), is("invalid-interval"));
+
+        assertThat(leafListInfo.getDataType().getDataType(), is(YangDataTypes.UNION));
+        assertThat(leafListInfo.getDataType().getDataTypeName(), is("union"));
+
+        YangUnion yangUnion = (YangUnion) leafListInfo.getDataType().getDataTypeExtendedInfo();
+
+        List<YangType<?>> typeList = yangUnion.getTypeList();
+        ListIterator<YangType<?>> typeListIterator = typeList.listIterator();
+        YangType<?> yangType = typeListIterator.next();
+
+        assertThat(yangType.getDataTypeName(), is("int32"));
+        assertThat(yangType.getDataType(), is(YangDataTypes.INT32));
+
+        YangType<?> yangTypeEnum = typeListIterator.next();
+
+        assertThat(yangTypeEnum.getDataTypeName(), is("enumeration"));
+        assertThat(yangTypeEnum.getDataType(), is(YangDataTypes.ENUMERATION));
+    }
+
+    /**
+     * Checks union with empty type.
+     */
+    @Test (expected = ParserException.class)
+    public void processUnionWithEmptyType() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/UnionWithEmptyType.yang");
+    }
+}
diff --git a/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/UsesListenerTest.java b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/UsesListenerTest.java
new file mode 100644
index 0000000..56c6cdd
--- /dev/null
+++ b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/UsesListenerTest.java
@@ -0,0 +1,122 @@
+/*
+ * Copyright 2016 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.yangutils.parser.impl.listeners;
+
+import java.io.IOException;
+import org.junit.Test;
+import org.onosproject.yangutils.datamodel.YangContainer;
+import org.onosproject.yangutils.datamodel.YangList;
+import org.onosproject.yangutils.datamodel.YangModule;
+import org.onosproject.yangutils.datamodel.YangNode;
+import org.onosproject.yangutils.datamodel.YangNodeType;
+import org.onosproject.yangutils.datamodel.YangStatusType;
+import org.onosproject.yangutils.datamodel.YangUses;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+import org.onosproject.yangutils.parser.impl.YangUtilsParserManager;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.Is.is;
+
+/**
+ * Test cases for testing uses listener.
+ */
+public class UsesListenerTest {
+
+    private final YangUtilsParserManager manager = new YangUtilsParserManager();
+
+    /**
+     * Checks uses statement inside module.
+     */
+    @Test
+    public void processUsesInModule() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/UsesInModule.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangUses yangUses = (YangUses) yangNode.getChild();
+        assertThat(yangUses.getName(), is("endpoint"));
+    }
+
+    /**
+     * Checks uses statement inside container.
+     */
+    @Test
+    public void processUsesInContainer() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/UsesInContainer.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangContainer yangContainer = (YangContainer) yangNode.getChild();
+        assertThat(yangContainer.getName(), is("valid"));
+
+        YangUses yangUses = (YangUses) yangContainer.getChild();
+        assertThat(yangUses.getName(), is("endpoint"));
+
+        // Check attributes associated with uses.
+        assertThat(yangUses.getStatus(), is(YangStatusType.CURRENT));
+        assertThat(yangUses.getReference(), is("\"RFC 6020\""));
+        assertThat(yangUses.getDescription(), is("\"grouping under test\""));
+    }
+
+    /**
+     * Checks uses statement inside list.
+     */
+    @Test
+    public void processUsesInList() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/UsesInList.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        YangList yangList = (YangList) yangNode.getChild();
+        assertThat(yangList.getName(), is("valid"));
+
+        YangUses yangUses = (YangUses) yangList.getChild();
+        assertThat(yangUses.getName(), is("endpoint"));
+
+        // Check attributes associated with uses.
+        assertThat(yangUses.getStatus(), is(YangStatusType.CURRENT));
+        assertThat(yangUses.getReference(), is("\"RFC 6020\""));
+        assertThat(yangUses.getDescription(), is("\"grouping under test\""));
+    }
+}
diff --git a/utils/yangutils/src/test/resources/CaseChoiceHierarchy.yang b/utils/yangutils/src/test/resources/CaseChoiceHierarchy.yang
index 16b4047..28d110e 100644
--- a/utils/yangutils/src/test/resources/CaseChoiceHierarchy.yang
+++ b/utils/yangutils/src/test/resources/CaseChoiceHierarchy.yang
@@ -2,22 +2,22 @@
     yang-version 1;
     namespace http://huawei.com;
     prefix Ant;
-     container food {
-       choice snack {
-           case sports-arena {
-               leaf pretzel {
-                   type empty;
-               }
-           }
-           case late-night {
-               choice dinner {
-                  case late-night {
-                   leaf beer {
-                       type empty;
-                   }
-               }
-           }
-       }
+    container food {
+        choice snack {
+            case sports-arena {
+                leaf pretzel {
+                    type empty;
+                }
+            }
+            case late-night {
+                choice dinner {
+                    case late-night {
+                        leaf beer {
+                            type empty;
+                        }
+                    }
+                }
+            }
+        }
     }
-  }
 }
diff --git a/utils/yangutils/src/test/resources/ConfigFalseParentContainerChildList.yang b/utils/yangutils/src/test/resources/ConfigFalseParentContainerChildList.yang
index 78fbe15..ffc6f60 100644
--- a/utils/yangutils/src/test/resources/ConfigFalseParentContainerChildList.yang
+++ b/utils/yangutils/src/test/resources/ConfigFalseParentContainerChildList.yang
@@ -4,7 +4,7 @@
     prefix Ant;
     container valid {
         config false;
-    	list valid {
+        list valid {
             key "invalid-interval";
             config true;
             leaf invalid-interval {
diff --git a/utils/yangutils/src/test/resources/ConfigFalseParentListChildContainer.yang b/utils/yangutils/src/test/resources/ConfigFalseParentListChildContainer.yang
index 5a84595..3158dd4 100644
--- a/utils/yangutils/src/test/resources/ConfigFalseParentListChildContainer.yang
+++ b/utils/yangutils/src/test/resources/ConfigFalseParentListChildContainer.yang
@@ -11,7 +11,7 @@
             status current;
             reference "RFC 6020";
         }
-        container valid { 
+        container valid {
             config true;
             leaf invalid-interval {
                 type "uint16";
@@ -19,6 +19,6 @@
                 status current;
                 reference "RFC 6020";
             }
-        }        
+        }
     }
 }
\ No newline at end of file
diff --git a/utils/yangutils/src/test/resources/DuplicateGroupingInContainer.yang b/utils/yangutils/src/test/resources/DuplicateGroupingInContainer.yang
new file mode 100644
index 0000000..f130797
--- /dev/null
+++ b/utils/yangutils/src/test/resources/DuplicateGroupingInContainer.yang
@@ -0,0 +1,23 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    container valid {
+        grouping endpoint {
+            leaf address {
+                type ip-address;
+            }
+            leaf port {
+                type port-number;
+            }
+        }
+        grouping endpoint {
+            leaf address {
+                type ip-address;
+            }
+            leaf port {
+                type port-number;
+            }
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/DuplicateGroupingInList.yang b/utils/yangutils/src/test/resources/DuplicateGroupingInList.yang
new file mode 100644
index 0000000..2457cbe
--- /dev/null
+++ b/utils/yangutils/src/test/resources/DuplicateGroupingInList.yang
@@ -0,0 +1,33 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    list valid {
+        key address;
+        grouping endpoint {
+            description "grouping under test";
+            status current;
+            reference "RFC 6020";
+            leaf address {
+                type ip-address;
+            }
+            leaf port {
+                type port-number;
+            }
+        }
+        leaf address {
+            type ip;
+        }
+        grouping endpoint {
+            description "grouping under test";
+            status current;
+            reference "RFC 6020";
+            leaf address {
+                type ip-address;
+            }
+            leaf port {
+                type port-number;
+            }
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/DuplicateGroupingInModule.yang b/utils/yangutils/src/test/resources/DuplicateGroupingInModule.yang
new file mode 100644
index 0000000..d18b166
--- /dev/null
+++ b/utils/yangutils/src/test/resources/DuplicateGroupingInModule.yang
@@ -0,0 +1,21 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    grouping endpoint {
+        leaf address {
+            type ip-address;
+        }
+        leaf port {
+            type port-number;
+        }
+    }
+    grouping endpoint {
+        leaf address {
+            type ip-address;
+        }
+        leaf port {
+            type port-number;
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/DuplicateLeafInHierarchy.yang b/utils/yangutils/src/test/resources/DuplicateLeafInHierarchy.yang
index c727cb7..e23f04c 100644
--- a/utils/yangutils/src/test/resources/DuplicateLeafInHierarchy.yang
+++ b/utils/yangutils/src/test/resources/DuplicateLeafInHierarchy.yang
@@ -2,22 +2,22 @@
     yang-version 1;
     namespace http://huawei.com;
     prefix Ant;
-     container food {
-       choice snack {
-           case sports-arena {
-               leaf pretzel {
-                   type empty;
-               }
-           }
-           case late-night {
-               choice lunch {
-                  case late {
-                   leaf pretzel {
-                       type empty;
-                   }
-               }
-           }
-       }
+    container food {
+        choice snack {
+            case sports-arena {
+                leaf pretzel {
+                    type empty;
+                }
+            }
+            case late-night {
+                choice lunch {
+                    case late {
+                        leaf pretzel {
+                            type empty;
+                        }
+                    }
+                }
+            }
+        }
     }
-  }
 }
diff --git a/utils/yangutils/src/test/resources/EnumWithDuplicateName.yang b/utils/yangutils/src/test/resources/EnumWithDuplicateName.yang
index d81558f..47c3a85 100644
--- a/utils/yangutils/src/test/resources/EnumWithDuplicateName.yang
+++ b/utils/yangutils/src/test/resources/EnumWithDuplicateName.yang
@@ -4,11 +4,11 @@
     prefix Ant;
     leaf speed {
         type enumeration {
-          enum 10m;
-          enum 100m;
-          enum 10m {
-	     value 11;
-          }
+            enum 10m;
+            enum 100m;
+            enum 10m {
+                value 11;
+            }
         }
     }
 }
diff --git a/utils/yangutils/src/test/resources/GroupingAttributes.yang b/utils/yangutils/src/test/resources/GroupingAttributes.yang
new file mode 100644
index 0000000..7eb3880
--- /dev/null
+++ b/utils/yangutils/src/test/resources/GroupingAttributes.yang
@@ -0,0 +1,22 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    list valid {
+        key address;
+        leaf address {
+            type ip;
+        }
+        grouping endpoint {
+            description "grouping under test";
+            status current;
+            reference "RFC 6020";
+            leaf address {
+                type ip-address;
+            }
+            leaf port {
+                type port-number;
+            }
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/GroupingInContainer.yang b/utils/yangutils/src/test/resources/GroupingInContainer.yang
new file mode 100644
index 0000000..be9e7e8
--- /dev/null
+++ b/utils/yangutils/src/test/resources/GroupingInContainer.yang
@@ -0,0 +1,15 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    container valid {
+        grouping endpoint {
+            leaf address {
+                type ip-address;
+            }
+            leaf port {
+                type port-number;
+            }
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/GroupingInList.yang b/utils/yangutils/src/test/resources/GroupingInList.yang
new file mode 100644
index 0000000..2cdf7d1
--- /dev/null
+++ b/utils/yangutils/src/test/resources/GroupingInList.yang
@@ -0,0 +1,19 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    list valid {
+        key address;
+        leaf address {
+            type ip;
+        }
+        grouping endpoint {
+            leaf address {
+                type ip-address;
+            }
+            leaf port {
+                type port-number;
+            }
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/GroupingInModule.yang b/utils/yangutils/src/test/resources/GroupingInModule.yang
new file mode 100644
index 0000000..d0a31c1
--- /dev/null
+++ b/utils/yangutils/src/test/resources/GroupingInModule.yang
@@ -0,0 +1,13 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    grouping endpoint {
+        leaf address {
+            type ip-address;
+        }
+        leaf port {
+            type port-number;
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/ShortCaseListenerWithContainer.yang b/utils/yangutils/src/test/resources/ShortCaseListenerWithContainer.yang
index 0e4ff2d..166eeb0 100644
--- a/utils/yangutils/src/test/resources/ShortCaseListenerWithContainer.yang
+++ b/utils/yangutils/src/test/resources/ShortCaseListenerWithContainer.yang
@@ -2,14 +2,14 @@
     yang-version 1;
     namespace http://huawei.com;
     prefix Ant;
-     container food {
-       choice snack {
-           container sports-arena {
-               leaf pretzel {
-                   type empty;
-               }
-           }
-       }
+        container food {
+            choice snack {
+                container sports-arena {
+                    leaf pretzel {
+                        type empty;
+                    }
+                }
+            }
+        }
     }
-  }
 }
diff --git a/utils/yangutils/src/test/resources/ShortCaseListenerWithList.yang b/utils/yangutils/src/test/resources/ShortCaseListenerWithList.yang
index 2ba25d9..eb03fca 100644
--- a/utils/yangutils/src/test/resources/ShortCaseListenerWithList.yang
+++ b/utils/yangutils/src/test/resources/ShortCaseListenerWithList.yang
@@ -2,15 +2,15 @@
     yang-version 1;
     namespace http://huawei.com;
     prefix Ant;
-     container food {
-       choice snack {
-           list sports-arena {
-               key "pretzel";
-               leaf pretzel {
-                   type int32;
-               }
-           }
-       }
+        container food {
+            choice snack {
+                list sports-arena {
+                    key "pretzel";
+                    leaf pretzel {
+                        type int32;
+                    }
+                }
+            }
+        }
     }
-  }
 }
diff --git a/utils/yangutils/src/test/resources/UnionWhenTypeInLeaf.yang b/utils/yangutils/src/test/resources/UnionWhenTypeInLeaf.yang
new file mode 100644
index 0000000..65c0369
--- /dev/null
+++ b/utils/yangutils/src/test/resources/UnionWhenTypeInLeaf.yang
@@ -0,0 +1,16 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    list valid {
+        key "invalid-interval";
+        leaf invalid-interval {
+            type union {
+                type int32;
+                type enumeration {
+                    enum "unbounded";
+                }
+            }
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/UnionWhenTypeInLeafList.yang b/utils/yangutils/src/test/resources/UnionWhenTypeInLeafList.yang
new file mode 100644
index 0000000..df2b428
--- /dev/null
+++ b/utils/yangutils/src/test/resources/UnionWhenTypeInLeafList.yang
@@ -0,0 +1,16 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    list valid {
+        key "invalid-interval";
+        leaf-list invalid-interval {
+            type union {
+            type int32;
+            type enumeration {
+                    enum "unbounded";
+                }
+            }
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/UnionWithEmptyType.yang b/utils/yangutils/src/test/resources/UnionWithEmptyType.yang
new file mode 100644
index 0000000..81e8795
--- /dev/null
+++ b/utils/yangutils/src/test/resources/UnionWithEmptyType.yang
@@ -0,0 +1,16 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    list valid {
+        key "invalid-interval";
+        leaf invalid-interval {
+            type union {
+                type empty;
+                type enumeration {
+                    enum "unbounded";
+                }
+            }
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/UsesInContainer.yang b/utils/yangutils/src/test/resources/UsesInContainer.yang
new file mode 100644
index 0000000..9fb5fbf
--- /dev/null
+++ b/utils/yangutils/src/test/resources/UsesInContainer.yang
@@ -0,0 +1,12 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    container valid {
+        uses endpoint {
+            description "grouping under test";
+            status current;
+            reference "RFC 6020";
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/UsesInList.yang b/utils/yangutils/src/test/resources/UsesInList.yang
new file mode 100644
index 0000000..6443cfa
--- /dev/null
+++ b/utils/yangutils/src/test/resources/UsesInList.yang
@@ -0,0 +1,16 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    list valid {
+        key address;
+        leaf address {
+            type ip;
+        }
+        uses endpoint {
+            description "grouping under test";
+            status current;
+            reference "RFC 6020";
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/UsesInModule.yang b/utils/yangutils/src/test/resources/UsesInModule.yang
new file mode 100644
index 0000000..a0a05f4
--- /dev/null
+++ b/utils/yangutils/src/test/resources/UsesInModule.yang
@@ -0,0 +1,6 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    uses endpoint;
+}
diff --git a/utils/yangutils/src/test/resources/ValidSameGroupingEntryInModuleAndContainer.yang b/utils/yangutils/src/test/resources/ValidSameGroupingEntryInModuleAndContainer.yang
new file mode 100644
index 0000000..2580cdd
--- /dev/null
+++ b/utils/yangutils/src/test/resources/ValidSameGroupingEntryInModuleAndContainer.yang
@@ -0,0 +1,23 @@
+module Test {
+    yang-version 1;
+    namespace http://huawei.com;
+    prefix Ant;
+    grouping endpoint {
+        leaf address {
+            type ip-address;
+        }
+    leaf port {
+        type port-number;
+        }
+    }
+    container valid {
+        grouping endpoint {
+            leaf address {
+                type ip-address;
+            }
+            leaf port {
+                type port-number;
+            }
+        }
+    }
+}
diff --git a/utils/yangutils/src/test/resources/ValueAndAutoStatement.yang b/utils/yangutils/src/test/resources/ValueAndAutoStatement.yang
index 31f098e..89ba403 100644
--- a/utils/yangutils/src/test/resources/ValueAndAutoStatement.yang
+++ b/utils/yangutils/src/test/resources/ValueAndAutoStatement.yang
@@ -4,13 +4,13 @@
     prefix Ant;
     leaf speed {
         type enumeration {
-          enum 10m {
-	     value 10;
-          }
-          enum 100m;
-          enum auto {
-	     value 1000;
-          }
+            enum 10m {
+                value 10;
+            }
+            enum 100m;
+            enum auto {
+                value 1000;
+            }
         }
     }
 }