[ONOS-3905, ONOS-3901, ONOS-3900] choice, grouping and augment data model support.

Change-Id: Iaee5175e4e06249f5b56192f4744e9297289194c

+/*
+ * 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.datamodel;
+
+import java.util.LinkedList;
+import java.util.List;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*-
+ * Reference RFC 6020.
+ *
+ * The "augment" statement allows a module or submodule to add to the
+ *  schema tree defined in an external module, or the current module and
+ *  its submodules, and to add to the nodes from a grouping in a "uses"
+ *  statement.  The argument is a string that identifies a node in the
+ *  schema tree.  This node is called the augment's target node.  The
+ *  target node MUST be either a container, list, choice, case, input,
+ *  output, or notification node.  It is augmented with the nodes defined
+ *  in the sub-statements that follow the "augment" statement.
+ *
+ *  The argument string is a schema node identifier.
+ *  If the "augment" statement is on the top level in a module or
+ *  submodule, the absolute form of a schema node identifier
+ *  MUST be used.  If the "augment" statement is a sub-statement to the
+ *  "uses" statement, the descendant form MUST be used.
+ *
+ *  If the target node is a container, list, case, input, output, or
+ *  notification node, the "container", "leaf", "list", "leaf-list",
+ *  "uses", and "choice" statements can be used within the "augment"
+ *  statement.
+ *
+ *  If the target node is a choice node, the "case" statement, or a case
+ *  shorthand statement can be used within the "augment" statement.
+ *
+ *   If the target node is in another module, then nodes added by the
+ *  augmentation MUST NOT be mandatory nodes.
+ *
+ *  The "augment" statement MUST NOT add multiple nodes with the same
+ *  name from the same module to the target node.
+ *  The augment's sub-statements
+ *
+ *                +--------------+---------+-------------+------------------+
+ *                | substatement | section | cardinality |data model mapping|
+ *                +--------------+---------+-------------+------------------+
+ *                | anyxml       | 7.10    | 0..n        |-not supported    |
+ *                | case         | 7.9.2   | 0..n        |-child nodes      |
+ *                | choice       | 7.9     | 0..n        |-child nodes      |
+ *                | container    | 7.5     | 0..n        |-child nodes      |
+ *                | description  | 7.19.3  | 0..1        |-string           |
+ *                | if-feature   | 7.18.2  | 0..n        |-TODO             |
+ *                | leaf         | 7.6     | 0..n        |-YangLeaf         |
+ *                | leaf-list    | 7.7     | 0..n        |-YangLeafList     |
+ *                | list         | 7.8     | 0..n        |-child nodes      |
+ *                | reference    | 7.19.4  | 0..1        |-String           |
+ *                | status       | 7.19.2  | 0..1        |-YangStatus       |
+ *                | uses         | 7.12    | 0..n        |-child nodes      |
+ *                | when         | 7.19.5  | 0..1        |-TODO             |
+ *                +--------------+---------+-------------+------------------+
+ */
+/**
+ * Data model node to maintain information defined in YANG augment.
+ */
+public class YangAugment extends YangNode
+        implements YangLeavesHolder, YangCommonInfo, Parsable {
+
+    /**
+     * Augment target node.
+     */
+    private String targetNode;
+
+    /**
+     * description of augment.
+     */
+    private String description;
+
+    /**
+     * List of leaves.
+     */
+    @SuppressWarnings("rawtypes")
+    private List<YangLeaf> listOfLeaf;
+
+    /**
+     * List of leaf-lists.
+     */
+    @SuppressWarnings("rawtypes")
+    private List<YangLeafList> listOfLeafList;
+
+    /**
+     * reference.
+     */
+    private String reference;
+
+    /**
+     * Status of the node.
+     */
+    private YangStatusType status;
+
+    /**
+     * Create a YANG augment node.
+     */
+    public YangAugment() {
+        super(YangNodeType.AUGMENT_NODE);
+    }
+
+    /**
+     * Get the augmented node.
+     *
+     * @return the augmented node.
+     */
+    public String getTargetNode() {
+        return targetNode;
+    }
+
+    /**
+     * Set the augmented node.
+     *
+     * @param targetNode the augmented node.
+     */
+    public void setTargetNode(String targetNode) {
+        this.targetNode = targetNode;
+    }
+
+    /**
+     * Get the description.
+     *
+     * @return the description.
+     */
+    public String getDescription() {
+        return description;
+    }
+
+    /**
+     * Set the description.
+     *
+     * @param description set the description.
+     */
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    /**
+     * Get the list of leaves.
+     *
+     * @return the list of leaves.
+     */
+    @SuppressWarnings("rawtypes")
+    public List<YangLeaf> getListOfLeaf() {
+        return listOfLeaf;
+    }
+
+    /**
+     * Set the list of leaves.
+     *
+     * @param leafsList the list of leaf to set.
+     */
+    @SuppressWarnings("rawtypes")
+    private void setListOfLeaf(List<YangLeaf> leafsList) {
+        listOfLeaf = leafsList;
+    }
+
+    /**
+     * Add a leaf.
+     *
+     * @param leaf the leaf to be added.
+     */
+    @SuppressWarnings("rawtypes")
+    public void addLeaf(YangLeaf<?> leaf) {
+        if (getListOfLeaf() == null) {
+            setListOfLeaf(new LinkedList<YangLeaf>());
+        }
+
+        getListOfLeaf().add(leaf);
+    }
+
+    /**
+     * Get the list of leaf-list.
+     *
+     * @return the list of leaf-list.
+     */
+    @SuppressWarnings("rawtypes")
+    public List<YangLeafList> getListOfLeafList() {
+        return listOfLeafList;
+    }
+
+    /**
+     * Set the list of leaf-list.
+     *
+     * @param listOfLeafList the list of leaf-list to set.
+     */
+    @SuppressWarnings("rawtypes")
+    private void setListOfLeafList(List<YangLeafList> listOfLeafList) {
+        this.listOfLeafList = listOfLeafList;
+    }
+
+    /**
+     * Add a leaf-list.
+     *
+     * @param leafList the leaf-list to be added.
+     */
+    @SuppressWarnings("rawtypes")
+    public void addLeafList(YangLeafList<?> leafList) {
+        if (getListOfLeafList() == null) {
+            setListOfLeafList(new LinkedList<YangLeafList>());
+        }
+
+        getListOfLeafList().add(leafList);
+    }
+
+    /**
+     * Get the textual reference.
+     *
+     * @return the reference.
+     */
+    public String getReference() {
+        return reference;
+    }
+
+    /**
+     * Set the textual reference.
+     *
+     * @param reference the reference to set.
+     */
+    public void setReference(String reference) {
+        this.reference = reference;
+    }
+
+    /**
+     * Get the status.
+     *
+     * @return the status.
+     */
+    public YangStatusType getStatus() {
+        return status;
+    }
+
+    /**
+     * Set the status.
+     *
+     * @param status the status to set.
+     */
+    public void setStatus(YangStatusType status) {
+        this.status = status;
+    }
+
+    /**
+     * Returns the type of the data as belongs-to.
+     *
+     * @return returns AUGMENT_DATA.
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.AUGMENT_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getName()
+     */
+    @Override
+    public String getName() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setName(java.lang.String)
+     */
+    @Override
+    public void setName(String name) {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getPackage()
+     */
+    @Override
+    public String getPackage() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setPackage(java.lang.String)
+     */
+    @Override
+    public void setPackage(String pkg) {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeEntry()
+     */
+    public void generateJavaCodeEntry() {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeExit()
+     */
+    public void generateJavaCodeExit() {
+        // TODO Auto-generated method stub
+
+    }
+}

+/*
+ * 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.datamodel;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*-
+ *  The "bit" statement, which is a sub-statement to the "type" statement,
+ *  MUST be present if the type is "bits".  It is repeatedly used to
+ *  specify each assigned named bit of a bits type.  It takes as an
+ *  argument a string that is the assigned name of the bit.  It is
+ *  followed by a block of sub-statements that holds detailed bit
+ *  information.
+ *  All assigned names in a bits type MUST be unique.
+ *
+ *  The bit's sub-statements
+ *
+ *                +--------------+---------+-------------+------------------+
+ *                | substatement | section | cardinality |data model mapping|
+ *                +--------------+---------+-------------+------------------+
+ *                | description  | 7.19.3  | 0..1        | - string         |
+ *                | reference    | 7.19.4  | 0..1        | - string         |
+ *                | status       | 7.19.2  | 0..1        | - YangStatus     |
+ *                | position     | 9.7.4.2 | 0..1        | - int            |
+ *                +--------------+---------+-------------+------------------+
+ */
+
+/**
+ * Maintains the bit data type information.
+ */
+public class YangBit implements YangCommonInfo, Parsable {
+
+    /**
+     * Name of the bit.
+     */
+    private String bitName;
+
+    /**
+     * Description of the bit field.
+     */
+    private String description;
+
+    /**
+     * reference info of the bit field.
+     */
+    private String reference;
+
+    /**
+     * Status of the bit field.
+     */
+    private YangStatusType status;
+
+    /**
+     * position of the bit whose name bit is described.
+     */
+    private int position;
+
+    /**
+     * Create a YANG bit type object.
+     */
+    public YangBit() {
+
+    }
+
+    /**
+     * Get the bit name.
+     *
+     * @return the bit name.
+     */
+    public String getBitName() {
+        return bitName;
+    }
+
+    /**
+     * Set the bit name.
+     *
+     * @param bitName the bit name to set.
+     */
+    public void setBitName(String bitName) {
+        this.bitName = bitName;
+    }
+
+    /**
+     * Get the description.
+     *
+     * @return the description.
+     */
+    public String getDescription() {
+        return description;
+    }
+
+    /**
+     * Set the description.
+     *
+     * @param description set the description.
+     */
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    /**
+     * Get the textual reference.
+     *
+     * @return the reference.
+     */
+    public String getReference() {
+        return reference;
+    }
+
+    /**
+     * Set the textual reference.
+     *
+     * @param reference the reference to set.
+     */
+    public void setReference(String reference) {
+        this.reference = reference;
+    }
+
+    /**
+     * Get the status.
+     *
+     * @return the status.
+     */
+    public YangStatusType getStatus() {
+        return status;
+    }
+
+    /**
+     * Set the status.
+     *
+     * @param status the status to set.
+     */
+    public void setStatus(YangStatusType status) {
+        this.status = status;
+    }
+
+    /**
+     * Get the bit position.
+     *
+     * @return the position
+     */
+    public int getPosition() {
+        return position;
+    }
+
+    /**
+     * Set the bit position.
+     *
+     * @param position the position to set.
+     */
+    public void setPosition(int position) {
+        this.position = position;
+    }
+
+    /**
+     * Returns the type of the data.
+     *
+     * @return ParsedDataType returns BIT_DATA
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.BIT_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+}

+/*
+ * 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.datamodel;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*
+ * Reference RFC 6020.
+ *
+ * The bits built-in type represents a bit set.  That is, a bits value
+ * is a set of flags identified by small integer position numbers
+ * starting at 0.  Each bit number has an assigned name.
+ */
+
+/**
+ * Maintains the bits data type information.
+ */
+public class YangBits implements Parsable {
+
+    private Set<YangBit> bitSet;
+
+    /**
+     * Create a YANG bits type object.
+     */
+    public YangBits() {
+        setBitSet(new HashSet<YangBit>());
+    }
+
+    /**
+     * Get the bit set.
+     *
+     * @return the bit set
+     */
+    public Set<YangBit> getBitSet() {
+        return bitSet;
+    }
+
+    /**
+     * set the bit set.
+     *
+     * @param bitSet the bit set
+     */
+    private void setBitSet(Set<YangBit> bitSet) {
+        this.bitSet = bitSet;
+    }
+
+    /**
+     * Add bit info.
+     *
+     * @param bitInfo the bit Info to add.
+     */
+    public void addBitInfo(YangBit bitInfo) {
+        getBitSet().add(bitInfo);
+    }
+
+    /**
+     * Returns the type of the data.
+     *
+     * @return ParsedDataType returns BITS_DATA
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.BITS_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+}

+/*
+ * 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.datamodel;
+
+import java.util.LinkedList;
+import java.util.List;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*-
+ * Reference RFC 6020.
+ *
+ * The "case" statement is used to define branches of the choice. It takes as an
+ * argument an identifier, followed by a block of sub-statements that holds
+ * detailed case information.
+ *
+ * The identifier is used to identify the case node in the schema tree. A case
+ * node does not exist in the data tree.
+ *
+ * Within a "case" statement, the "anyxml", "choice", "container", "leaf",
+ * "list", "leaf-list", and "uses" statements can be used to define child nodes
+ * to the case node. The identifiers of all these child nodes MUST be unique
+ * within all cases in a choice. For example, the following is illegal:
+ *
+ * choice interface-type {     // This example is illegal YANG
+ *        case a {
+ *            leaf ethernet { ... }
+ *        }
+ *        case b {
+ *            container ethernet { ...}
+ *        }
+ *    }
+ *
+ *  As a shorthand, the "case" statement can be omitted if the branch
+ *  contains a single "anyxml", "container", "leaf", "list", or
+ *  "leaf-list" statement.  In this case, the identifier of the case node
+ *  is the same as the identifier in the branch statement.  The following
+ *  example:
+ *
+ *    choice interface-type {
+ *        container ethernet { ... }
+ *    }
+ *
+ *  is equivalent to:
+ *
+ *    choice interface-type {
+ *        case ethernet {
+ *            container ethernet { ... }
+ *        }
+ *    }
+ *
+ *  The case identifier MUST be unique within a choice.
+ *
+ *  The case's sub-statements
+ *
+ *                +--------------+---------+-------------+------------------+
+ *                | substatement | section | cardinality |data model mapping|
+ *                +--------------+---------+-------------+------------------+
+ *                | anyxml       | 7.10    | 0..n        |-not supported    |
+ *                | choice       | 7.9     | 0..n        |-child nodes      |
+ *                | container    | 7.5     | 0..n        |-child nodes      |
+ *                | description  | 7.19.3  | 0..1        |-string           |
+ *                | if-feature   | 7.18.2  | 0..n        |-TODO             |
+ *                | leaf         | 7.6     | 0..n        |-YangLeaf         |
+ *                | leaf-list    | 7.7     | 0..n        |-YangLeafList     |
+ *                | list         | 7.8     | 0..n        |-child nodes      |
+ *                | reference    | 7.19.4  | 0..1        |-string           |
+ *                | status       | 7.19.2  | 0..1        |-YangStatus       |
+ *                | uses         | 7.12    | 0..n        |-child node       |
+ *                | when         | 7.19.5  | 0..1        |-TODO             |
+ *                +--------------+---------+-------------+------------------+
+ */
+/**
+ * Data model node to maintain information defined in YANG case.
+ */
+public class YangCase extends YangNode
+        implements YangLeavesHolder, YangCommonInfo, Parsable {
+
+    /**
+     * Case name.
+     */
+    private String name;
+
+    // TODO: default field identification for the case
+
+    /**
+     * Description of container.
+     */
+    private String description;
+
+    /**
+     * List of leaves.
+     */
+    @SuppressWarnings("rawtypes")
+    private List<YangLeaf> listOfLeaf;
+
+    /**
+     * List of leaf lists.
+     */
+    @SuppressWarnings("rawtypes")
+    private List<YangLeafList> listOfLeafList;
+
+    /**
+     * Reference of the module.
+     */
+    private String reference;
+
+    /**
+     * Status of the node.
+     */
+    private YangStatusType status;
+
+    /**
+     * Create a choice node.
+     */
+    public YangCase() {
+        super(YangNodeType.CASE_NODE);
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getName()
+     */
+    @Override
+    public String getName() {
+        return name;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setName(java.lang.String)
+     */
+    @Override
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    /**
+     * Get the description.
+     *
+     * @return the description.
+     */
+    public String getDescription() {
+        return description;
+    }
+
+    /**
+     * Set the description.
+     *
+     * @param description set the description.
+     */
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    /**
+     * Get the list of leaves.
+     *
+     * @return the list of leaves.
+     */
+    @SuppressWarnings("rawtypes")
+    public List<YangLeaf> getListOfLeaf() {
+        return listOfLeaf;
+    }
+
+    /**
+     * Set the list of leaves.
+     *
+     * @param leafsList the list of leaf to set.
+     */
+    @SuppressWarnings("rawtypes")
+    private void setListOfLeaf(List<YangLeaf> leafsList) {
+        listOfLeaf = leafsList;
+    }
+
+    /**
+     * Add a leaf.
+     *
+     * @param leaf the leaf to be added.
+     */
+    @SuppressWarnings("rawtypes")
+    public void addLeaf(YangLeaf<?> leaf) {
+        if (getListOfLeaf() == null) {
+            setListOfLeaf(new LinkedList<YangLeaf>());
+        }
+
+        getListOfLeaf().add(leaf);
+    }
+
+    /**
+     * Get the list of leaf-list.
+     *
+     * @return the list of leaf-list.
+     */
+    @SuppressWarnings("rawtypes")
+    public List<YangLeafList> getListOfLeafList() {
+        return listOfLeafList;
+    }
+
+    /**
+     * Set the list of leaf-list.
+     *
+     * @param listOfLeafList the list of leaf-list to set.
+     */
+    @SuppressWarnings("rawtypes")
+    private void setListOfLeafList(List<YangLeafList> listOfLeafList) {
+        this.listOfLeafList = listOfLeafList;
+    }
+
+    /**
+     * Add a leaf-list.
+     *
+     * @param leafList the leaf-list to be added.
+     */
+    @SuppressWarnings("rawtypes")
+    public void addLeafList(YangLeafList<?> leafList) {
+        if (getListOfLeafList() == null) {
+            setListOfLeafList(new LinkedList<YangLeafList>());
+        }
+
+        getListOfLeafList().add(leafList);
+    }
+
+    /**
+     * Get the textual reference.
+     *
+     * @return the reference.
+     */
+    public String getReference() {
+        return reference;
+    }
+
+    /**
+     * Set the textual reference.
+     *
+     * @param reference the reference to set.
+     */
+    public void setReference(String reference) {
+        this.reference = reference;
+    }
+
+    /**
+     * Get the status.
+     *
+     * @return the status.
+     */
+    public YangStatusType getStatus() {
+        return status;
+    }
+
+    /**
+     * Set the status.
+     *
+     * @param status the status to set.
+     */
+    public void setStatus(YangStatusType status) {
+        this.status = status;
+    }
+
+    /**
+     * Returns the type of the data.
+     *
+     * @return returns CASE_DATA
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.CASE_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getPackage()
+     */
+    @Override
+    public String getPackage() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setPackage(java.lang.String)
+     */
+    @Override
+    public void setPackage(String pkg) {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeEntry()
+     */
+    public void generateJavaCodeEntry() {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeExit()
+     */
+    public void generateJavaCodeExit() {
+        // TODO Auto-generated method stub
+
+    }
+}

+/*
+ * 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.datamodel;
+
+import java.util.LinkedList;
+import java.util.List;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*-
+ * Reference RFC 6020.
+ *
+ * The "choice" statement defines a set of alternatives, only one of
+ *  which may exist at any one time.  The argument is an identifier,
+ *  followed by a block of sub-statements that holds detailed choice
+ *  information.  The identifier is used to identify the choice node in
+ *  the schema tree.  A choice node does not exist in the data tree.
+ *
+ *  A choice consists of a number of branches, defined with the "case"
+ *  sub-statement.  Each branch contains a number of child nodes.  The
+ *  nodes from at most one of the choice's branches exist at the same
+ *  time.
+ *
+ *  The choice's sub-statements
+ *
+ *                +--------------+---------+-------------+------------------+
+ *                | substatement | section | cardinality |data model mapping|
+ *                +--------------+---------+-------------+------------------+
+ *                | anyxml       | 7.10    | 0..n        |-not supported    |
+ *                | case         | 7.9.2   | 0..n        |-YangChoice       |
+ *                | config       | 7.19.1  | 0..1        |-boolean          |
+ *                | container    | 7.5     | 0..n        |-child case nodes |
+ *                | default      | 7.9.3   | 0..1        |-string           |
+ *                | description  | 7.19.3  | 0..1        |-string           |
+ *                | if-feature   | 7.18.2  | 0..n        |-TODO             |
+ *                | leaf         | 7.6     | 0..n        |-child case nodes |
+ *                | leaf-list    | 7.7     | 0..n        |-child case nodes |
+ *                | list         | 7.8     | 0..n        |-child case nodes |
+ *                | mandatory    | 7.9.4   | 0..1        |-string           |
+ *                | reference    | 7.19.4  | 0..1        |-string           |
+ *                | status       | 7.19.2  | 0..1        |-string           |
+ *                | when         | 7.19.5  | 0..1        |-TODO             |
+ *                +--------------+---------+-------------+------------------+
+ */
+/**
+ * Data model node to maintain information defined in YANG choice.
+ */
+public class YangChoice extends YangNode implements YangCommonInfo, Parsable {
+
+    /**
+     * Name of choice.
+     */
+    private String name;
+
+    /**
+     * List of cases for the current choice.
+     */
+    private List<YangCase> caseList;
+
+    /**
+     * If the choice represents config data.
+     */
+    private boolean isConfig;
+
+    /**
+     * Reference RFC 6020.
+     *
+     * The "default" statement indicates if a case should be considered as the
+     * default if no child nodes from any of the choice's cases exist. The
+     * argument is the identifier of the "case" statement. If the "default"
+     * statement is missing, there is no default case.
+     *
+     * The "default" statement MUST NOT be present on choices where "mandatory"
+     * is true.
+     *
+     * The default case is only important when considering the default values of
+     * nodes under the cases. The default values for nodes under the default
+     * case are used if none of the nodes under any of the cases are present.
+     *
+     * There MUST NOT be any mandatory nodes directly under the default case.
+     *
+     * Default values for child nodes under a case are only used if one of the
+     * nodes under that case is present, or if that case is the default case. If
+     * none of the nodes under a case are present and the case is not the
+     * default case, the default values of the cases' child nodes are ignored.
+     *
+     * the default case to be used if no case members is present.
+     */
+    private String defaultCase;
+
+    /**
+     * Description.
+     */
+    private String description;
+
+    /**
+     * Reference RFC 6020.
+     *
+     * The "mandatory" statement, which is optional, takes as an argument the
+     * string "true" or "false", and puts a constraint on valid data. If
+     * "mandatory" is "true", at least one node from exactly one of the choice's
+     * case branches MUST exist.
+     *
+     * If not specified, the default is "false".
+     *
+     * The behavior of the constraint depends on the type of the choice's
+     * closest ancestor node in the schema tree which is not a non-presence
+     * container:
+     *
+     * o If this ancestor is a case node, the constraint is enforced if any
+     * other node from the case exists.
+     *
+     * o Otherwise, it is enforced if the ancestor node exists.
+     */
+    private String mandatory;
+
+    /**
+     * reference of the choice.
+     */
+    private String reference;
+
+    /**
+     * Status of the node.
+     */
+    private YangStatusType status;
+
+    /**
+     * Create a Choice node.
+     */
+    public YangChoice() {
+        super(YangNodeType.CHOICE_NODE);
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getName()
+     */
+    @Override
+    public String getName() {
+        return name;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setName(java.lang.String)
+     */
+    @Override
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    /**
+     * Get the list of cases.
+     *
+     * @return the case list
+     */
+    public List<YangCase> getCaseList() {
+        return caseList;
+    }
+
+    /**
+     * Set the list of cases.
+     *
+     * @param caseList list of cases.
+     */
+    private void setCaseList(List<YangCase> caseList) {
+        this.caseList = caseList;
+    }
+
+    /**
+     * Add a case.
+     *
+     * @param newCase new case for the choice
+     */
+    public void addCase(YangCase newCase) {
+        if (getCaseList() == null) {
+            setCaseList(new LinkedList<YangCase>());
+        }
+
+        getCaseList().add(newCase);
+    }
+
+    /**
+     * Get config flag.
+     *
+     * @return the config flag.
+     */
+    public boolean isConfig() {
+        return isConfig;
+    }
+
+    /**
+     * Set config flag.
+     *
+     * @param isCfg the config flag.
+     */
+    public void setConfig(boolean isCfg) {
+        isConfig = isCfg;
+    }
+
+    /**
+     * Get the default case.
+     *
+     * @return the default case.
+     */
+    public String getDefaultCase() {
+        return defaultCase;
+    }
+
+    /**
+     * Set the default case.
+     *
+     * @param defaultCase the default case to set
+     */
+    public void setDefaultCase(String defaultCase) {
+        this.defaultCase = defaultCase;
+    }
+
+    /**
+     * Get the mandatory status.
+     *
+     * @return the mandatory status.
+     */
+    public String getMandatory() {
+        return mandatory;
+    }
+
+    /**
+     * Set the mandatory status.
+     *
+     * @param mandatory the mandatory status.
+     */
+    public void setMandatory(String mandatory) {
+        this.mandatory = mandatory;
+    }
+
+    /**
+     * Get the description.
+     *
+     * @return the description.
+     */
+    public String getDescription() {
+        return description;
+    }
+
+    /**
+     * Set the description.
+     *
+     * @param description set the description.
+     */
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    /**
+     * Get the textual reference.
+     *
+     * @return the reference.
+     */
+    public String getReference() {
+        return reference;
+    }
+
+    /**
+     * Set the textual reference.
+     *
+     * @param reference the reference to set.
+     */
+    public void setReference(String reference) {
+        this.reference = reference;
+    }
+
+    /**
+     * Get the status.
+     *
+     * @return the status.
+     */
+    public YangStatusType getStatus() {
+        return status;
+    }
+
+    /**
+     * Set the status.
+     *
+     * @param status the status to set.
+     */
+    public void setStatus(YangStatusType status) {
+        this.status = status;
+    }
+
+    /**
+     * Returns the type of the data.
+     *
+     * @return returns CHOICE_DATA
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.CHOICE_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getPackage()
+     */
+    @Override
+    public String getPackage() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setPackage(java.lang.String)
+     */
+    @Override
+    public void setPackage(String pkg) {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeEntry()
+     */
+    public void generateJavaCodeEntry() {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeExit()
+     */
+    public void generateJavaCodeExit() {
+        // TODO Auto-generated method stub
+
+    }
+}

+/*
+ * 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.datamodel;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*-
+ * The "ENUM" statement, which is a sub-statement to the "type"
+ *  statement, MUST be present if the type is "enumeration".  It is
+ *  repeatedly used to specify each assigned name of an enumeration type.
+ *  It takes as an argument a string which is the assigned name.  The
+ *  string MUST NOT be empty and MUST NOT have any leading or trailing
+ *  whitespace characters.  The use of Unicode control codes SHOULD be
+ *  avoided.
+ *
+ *  The statement is optionally followed by a block of sub-statements that
+ *  holds detailed ENUM information.
+ *  All assigned names in an enumeration MUST be unique.
+ *
+ *  The ENUM's sub-statements
+ *
+ *                +--------------+---------+-------------+------------------+
+ *                | substatement | section | cardinality |data model mapping|
+ *                +--------------+---------+-------------+------------------+
+ *                | description  | 7.19.3  | 0..1        | - string         |
+ *                | reference    | 7.19.4  | 0..1        | - string         |
+ *                | status       | 7.19.2  | 0..1        | - YangStatus     |
+ *                | value        | 9.6.4.2 | 0..1        | - int            |
+ *                +--------------+---------+-------------+------------------+
+ */
+
+/**
+ * Maintains the ENUM data type information.
+ */
+public class YangEnum implements YangCommonInfo, Parsable {
+
+    /**
+     * Named value for the ENUM.
+     */
+    private String namedValue;
+
+    /**
+     * Description of the ENUM value.
+     */
+    private String description;
+
+    /**
+     * Reference info of the ENUM value.
+     */
+    private String reference;
+
+    /**
+     * Status of the ENUM value.
+     */
+    private YangStatusType status;
+
+    /**
+     * value of ENUM.
+     */
+    private int value;
+
+    /**
+     * Create a YANG ENUM.
+     */
+    public YangEnum() {
+
+    }
+
+    /**
+     * Get the named value.
+     *
+     * @return the named value.
+     */
+    public String getNamedValue() {
+        return namedValue;
+    }
+
+    /**
+     * Set the named value.
+     *
+     * @param namedValue the named value to set.
+     */
+    public void setNamedValue(String namedValue) {
+        this.namedValue = namedValue;
+    }
+
+    /**
+     * Get the description.
+     *
+     * @return the description.
+     */
+    public String getDescription() {
+        return description;
+    }
+
+    /**
+     * Set the description.
+     *
+     * @param description set the description.
+     */
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    /**
+     * Get the textual reference.
+     *
+     * @return the reference.
+     */
+    public String getReference() {
+        return reference;
+    }
+
+    /**
+     * Set the textual reference.
+     *
+     * @param reference the reference to set.
+     */
+    public void setReference(String reference) {
+        this.reference = reference;
+    }
+
+    /**
+     * Get the status.
+     *
+     * @return the status.
+     */
+    public YangStatusType getStatus() {
+        return status;
+    }
+
+    /**
+     * Set the status.
+     *
+     * @param status the status to set.
+     */
+    public void setStatus(YangStatusType status) {
+        this.status = status;
+    }
+
+    /**
+     * Get the value.
+     *
+     * @return the value.
+     */
+    public int getValue() {
+        return value;
+    }
+
+    /**
+     * Set the value.
+     *
+     * @param value the value to set.
+     */
+    public void setValue(int value) {
+        this.value = value;
+    }
+
+    /**
+     * Returns the type of the data.
+     *
+     * @return ParsedDataType returns ENUM_DATA
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.ENUM_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+}

+/*
+ * 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.datamodel;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*
+ * The enumeration built-in type represents values from a set of
+ *  assigned names.
+ */
+
+/**
+ * Maintains the enumeration data type information.
+ */
+public class YangEnumeration extends YangNode implements Parsable {
+
+    /**
+     * Enumeration info set.
+     */
+    private Set<YangEnum> enumSet;
+
+    /**
+     * Create an enumeration object.
+     */
+    public YangEnumeration() {
+        super(YangNodeType.ENUMERATION_NODE);
+        setEnumSet(new HashSet<YangEnum>());
+
+    }
+
+    /**
+     * Get the ENUM set.
+     *
+     * @return the ENUM set
+     */
+    public Set<YangEnum> getEnumSet() {
+        return enumSet;
+    }
+
+    /**
+     * Set the ENUM set.
+     *
+     * @param enumSet the ENUM set to set
+     */
+    private void setEnumSet(Set<YangEnum> enumSet) {
+        this.enumSet = enumSet;
+    }
+
+    /**
+     * Add ENUM value.
+     *
+     * @param enumInfo the ENUM value of string
+     */
+    public void addEnumInfo(YangEnum enumInfo) {
+
+    }
+
+    /**
+     * Returns the type of the data.
+     *
+     * @return returns ENUMERATION_DATA
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.ENUMERATION_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getName()
+     */
+    @Override
+    public String getName() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setName(java.lang.String)
+     */
+    @Override
+    public void setName(String name) {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getPackage()
+     */
+    @Override
+    public String getPackage() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setPackage(java.lang.String)
+     */
+    @Override
+    public void setPackage(String pkg) {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeEntry()
+     */
+    public void generateJavaCodeEntry() {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeExit()
+     */
+    public void generateJavaCodeExit() {
+        // TODO Auto-generated method stub
+
+    }
+}

+/*
+ * 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.datamodel;
+
+import java.util.LinkedList;
+import java.util.List;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*-
+ * Reference RFC 6020.
+ *
+ *  The "grouping" statement is used to define a reusable block of nodes,
+ *  which may be used locally in the module, in modules that include it,
+ *  and by other modules that import from it.  It takes one argument,
+ *  which is an identifier, followed by a block of sub-statements that
+ *  holds detailed grouping information.
+ *
+ *  The "grouping" statement is not a data definition statement and, as
+ *  such, does not define any nodes in the schema tree.
+ *
+ *  A grouping is like a "structure" or a "record" in conventional
+ *  programming languages.
+ *  Once a grouping is defined, it can be referenced in a "uses"
+ *  statement.  A grouping MUST NOT reference itself,
+ *  neither directly nor indirectly through a chain of other groupings.
+ *
+ *  If the grouping is defined at the top level of a YANG module or
+ *  submodule, the grouping's identifier MUST be unique within the
+ *  module.
+ *
+ *  A grouping is more than just a mechanism for textual substitution,
+ *  but defines a collection of nodes.  Identifiers appearing inside the
+ *  grouping are resolved relative to the scope in which the grouping is
+ *  defined, not where it is used.  Prefix mappings, type names, grouping
+ *  names, and extension usage are evaluated in the hierarchy where the
+ *  "grouping" statement appears.  For extensions, this means that
+ *  extensions are applied to the grouping node, not the uses node.
+ *
+ *  The grouping's sub-statements
+ *
+ *                +--------------+---------+-------------+------------------+
+ *                | substatement | section | cardinality |data model mapping|
+ *                +--------------+---------+-------------+------------------+
+ *                | anyxml       | 7.10    | 0..n        |-not supported    |
+ *                | choice       | 7.9     | 0..n        |-child nodes      |
+ *                | container    | 7.5     | 0..n        |-child nodes      |
+ *                | description  | 7.19.3  | 0..1        |-string           |
+ *                | grouping     | 7.11    | 0..n        |-child nodes      |
+ *                | leaf         | 7.6     | 0..n        |-YangLeaf         |
+ *                | leaf-list    | 7.7     | 0..n        |-YangLeafList     |
+ *                | list         | 7.8     | 0..n        |-child nodes      |
+ *                | reference    | 7.19.4  | 0..1        |-string           |
+ *                | status       | 7.19.2  | 0..1        |-YangStatus       |
+ *                | typedef      | 7.3     | 0..n        |-child nodes      |
+ *                | uses         | 7.12    | 0..n        |-child nodes      |
+ *                +--------------+---------+-------------+------------------+
+ */
+
+/**
+ * Data model node to maintain information defined in YANG grouping.
+ */
+public class YangGrouping extends YangNode
+        implements YangLeavesHolder, YangCommonInfo, Parsable {
+
+    /**
+     * Name of the grouping.
+     */
+    private String name;
+
+    /**
+     * Description.
+     */
+    private String description;
+
+    /**
+     * List of leaves.
+     */
+    @SuppressWarnings("rawtypes")
+    private List<YangLeaf> listOfLeaf;
+
+    /**
+     * List of leaf lists.
+     */
+    @SuppressWarnings("rawtypes")
+    private List<YangLeafList> listOfLeafList;
+
+    /**
+     * Reference of the module.
+     */
+    private String reference;
+
+    /**
+     * Status of the node.
+     */
+    private YangStatusType status;
+
+    /**
+     * Creates the grouping node.
+     */
+    public YangGrouping() {
+        super(YangNodeType.GROUPING_NODE);
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getName()
+     */
+    @Override
+    public String getName() {
+        return name;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setName(java.lang.String)
+     */
+    @Override
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    /**
+     * Get the description.
+     *
+     * @return the description.
+     */
+    public String getDescription() {
+        return description;
+    }
+
+    /**
+     * Set the description.
+     *
+     * @param description set the description.
+     */
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    /**
+     * Get the list of leaves.
+     *
+     * @return the list of leaves.
+     */
+    @SuppressWarnings("rawtypes")
+    public List<YangLeaf> getListOfLeaf() {
+        return listOfLeaf;
+    }
+
+    /**
+     * Set the list of leaves.
+     *
+     * @param leafsList the list of leaf to set.
+     */
+    @SuppressWarnings("rawtypes")
+    private void setListOfLeaf(List<YangLeaf> leafsList) {
+        listOfLeaf = leafsList;
+    }
+
+    /**
+     * Add a leaf.
+     *
+     * @param leaf the leaf to be added.
+     */
+    @SuppressWarnings("rawtypes")
+    public void addLeaf(YangLeaf<?> leaf) {
+        if (getListOfLeaf() == null) {
+            setListOfLeaf(new LinkedList<YangLeaf>());
+        }
+
+        getListOfLeaf().add(leaf);
+    }
+
+    /**
+     * Get the list of leaf-list.
+     *
+     * @return the list of leaf-list.
+     */
+    @SuppressWarnings("rawtypes")
+    public List<YangLeafList> getListOfLeafList() {
+        return listOfLeafList;
+    }
+
+    /**
+     * Set the list of leaf-list.
+     *
+     * @param listOfLeafList the list of leaf-list to set.
+     */
+    @SuppressWarnings("rawtypes")
+    private void setListOfLeafList(List<YangLeafList> listOfLeafList) {
+        this.listOfLeafList = listOfLeafList;
+    }
+
+    /**
+     * Add a leaf-list.
+     *
+     * @param leafList the leaf-list to be added.
+     */
+    @SuppressWarnings("rawtypes")
+    public void addLeafList(YangLeafList<?> leafList) {
+        if (getListOfLeafList() == null) {
+            setListOfLeafList(new LinkedList<YangLeafList>());
+        }
+
+        getListOfLeafList().add(leafList);
+    }
+
+    /**
+     * Get the textual reference.
+     *
+     * @return the reference.
+     */
+    public String getReference() {
+        return reference;
+    }
+
+    /**
+     * Set the textual reference.
+     *
+     * @param reference the reference to set.
+     */
+    public void setReference(String reference) {
+        this.reference = reference;
+    }
+
+    /**
+     * Get the status.
+     *
+     * @return the status.
+     */
+    public YangStatusType getStatus() {
+        return status;
+    }
+
+    /**
+     * Set the status.
+     *
+     * @param status the status to set.
+     */
+    public void setStatus(YangStatusType status) {
+        this.status = status;
+    }
+
+    /**
+     * Returns the type of the data.
+     *
+     * @return returns GROUPING_DATA.
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.GROUPING_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeEntry()
+     */
+    public void generateJavaCodeEntry() {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeExit()
+     */
+    public void generateJavaCodeExit() {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getPackage()
+     */
+    @Override
+    public String getPackage() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setPackage(java.lang.String)
+     */
+    @Override
+    public void setPackage(String pkg) {
+        // TODO Auto-generated method stub
+
+    }
+}

+/*
+ * 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.datamodel;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*-
+ * The "must" statement, which is optional, takes as an argument a string that
+ * contains an XPath expression. It is used to formally declare a constraint
+ * on valid data.
+ *
+ * When a datastore is validated, all "must" constraints are conceptually
+ * evaluated once for each data node in the data tree, and for all leafs with
+ * default values in use. If a data node does not exist in the data tree, and
+ * it does not have a default value, its "must" statements are not evaluated.
+ *
+ * All such constraints MUST evaluate to true for the data to be valid.
+ *
+ *  The must's sub-statements
+ *
+ *                +---------------+---------+-------------+------------------+
+ *                | substatement  | section | cardinality |data model mapping|
+ *                +---------------+---------+-------------+------------------+
+ *                | description   | 7.19.3  | 0..1        | -string          |
+ *                | error-app-tag | 7.5.4.2 | 0..1        | -not supported   |
+ *                | error-message | 7.5.4.1 | 0..1        | -not supported   |
+ *                | reference     | 7.19.4  | 0..1        | -string          |
+ *                +---------------+---------+-------------+------------------+
+ */
+
+/**
+ * Maintain information defined in YANG must.
+ */
+public class YangMust implements YangDesc, YangReference, Parsable {
+
+    /**
+     * Constraint info.
+     */
+    private String constratint;
+
+    /**
+     * Description string.
+     */
+    private String description;
+
+    /**
+     * reference string.
+     */
+    private String reference;
+
+    /**
+     * Create a YANG must restriction.
+     */
+    public YangMust() {
+    }
+
+    /**
+     * Get the constraint.
+     *
+     * @return the constraint.
+     */
+    public String getConstratint() {
+        return constratint;
+    }
+
+    /**
+     * Set the constraint.
+     *
+     * @param constratint the constraint to set
+     */
+    public void setConstratint(String constratint) {
+        this.constratint = constratint;
+    }
+
+    /**
+     * Get the description.
+     *
+     * @return the description.
+     */
+    public String getDescription() {
+        return description;
+    }
+
+    /**
+     * Set the description.
+     *
+     * @param description set the description.
+     */
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    /**
+     * Get the textual reference.
+     *
+     * @return the reference.
+     */
+    public String getReference() {
+        return reference;
+    }
+
+    /**
+     * Set the textual reference.
+     *
+     * @param reference the reference to set.
+     */
+    public void setReference(String reference) {
+        this.reference = reference;
+    }
+
+    /**
+     * Returns the type of the parsed data.
+     *
+     * @return returns MUST_DATA
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.MUST_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+}

+/*
+ * 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.datamodel;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*-
+ * Reference RFC 6020.
+ *
+ * The "typedef" statement defines a new type that may be used locally in the
+ * module, in modules or submodules which include it, and by other modules that
+ * import from it. The new type is called the "derived type", and the type from
+ * which it was derived is called the "base type". All derived types can be
+ * traced back to a YANG built-in type.
+ *
+ * The "typedef" statement's argument is an identifier that is the name of the
+ * type to be defined, and MUST be followed by a block of sub-statements that
+ * holds detailed typedef information.
+ *
+ * The name of the type MUST NOT be one of the YANG built-in types. If the
+ * typedef is defined at the top level of a YANG module or submodule, the name
+ * of the type to be defined MUST be unique within the module.
+ * The typedef's sub-statements
+ *
+ *                +--------------+---------+-------------+------------------+
+ *                | substatement | section | cardinality |data model mapping|
+ *                +--------------+---------+-------------+------------------+
+ *                | default      | 7.3.4   | 0..1        |-string           |
+ *                | description  | 7.19.3  | 0..1        |-string           |
+ *                | reference    | 7.19.4  | 0..1        |-string           |
+ *                | status       | 7.19.2  | 0..1        |-YangStatus       |
+ *                | type         | 7.3.2   | 1           |-yangType         |
+ *                | units        | 7.3.3   | 0..1        |-string           |
+ *                +--------------+---------+-------------+------------------+
+ */
+/**
+ * Data model node to maintain information defined in YANG typedef.
+ */
+public class YangTypeDef extends YangNode implements YangCommonInfo, Parsable {
+
+    /**
+     * Name of derived data type.
+     */
+    private String derivedName;
+
+    /**
+     * Default value in string, needs to be converted to the target object,
+     * based on the type.
+     */
+    private String defaultValueInString;
+
+    /**
+     * Description of new type.
+     */
+    private String description;
+
+    /**
+     * reference string.
+     */
+    private String reference;
+
+    /**
+     * Status of the data type.
+     */
+    private YangStatusType status;
+
+    /**
+     * Derived data type.
+     */
+    @SuppressWarnings("rawtypes")
+    private YangType derivedType;
+
+    /**
+     * Units of the data type.
+     */
+    private String units;
+
+    /**
+     * Create a typedef node.
+     */
+    public YangTypeDef() {
+        super(YangNodeType.TYPEDEF_NODE);
+    }
+
+    /**
+     * Get the data type name.
+     *
+     * @return the data type name.
+     */
+    public String getDerivedName() {
+        return derivedName;
+    }
+
+    /**
+     * Set the data type name.
+     *
+     * @param derrivedName data type name.
+     */
+    public void setDerivedName(String derrivedName) {
+        derivedName = derrivedName;
+    }
+
+    /**
+     * Get the default value.
+     *
+     * @return the default value.
+     */
+    public String getDefaultValueInString() {
+        return defaultValueInString;
+    }
+
+    /**
+     * Set the default value.
+     *
+     * @param defaultValueInString the default value.
+     */
+    public void setDefaultValueInString(String defaultValueInString) {
+        this.defaultValueInString = defaultValueInString;
+    }
+
+    /**
+     * Get the description.
+     *
+     * @return the description.
+     */
+    public String getDescription() {
+        return description;
+    }
+
+    /**
+     * Set the description.
+     *
+     * @param description set the description.
+     */
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    /**
+     * Get the textual reference.
+     *
+     * @return the reference.
+     */
+    public String getReference() {
+        return reference;
+    }
+
+    /**
+     * Set the textual reference.
+     *
+     * @param reference the reference to set.
+     */
+    public void setReference(String reference) {
+        this.reference = reference;
+    }
+
+    /**
+     * Get the status.
+     *
+     * @return the status.
+     */
+    public YangStatusType getStatus() {
+        return status;
+    }
+
+    /**
+     * Set the status.
+     *
+     * @param status the status to set.
+     */
+    public void setStatus(YangStatusType status) {
+        this.status = status;
+    }
+
+    /**
+     * Get the referenced type.
+     *
+     * @return the referenced type.
+     */
+    @SuppressWarnings("rawtypes")
+    public YangType getDerivedType() {
+        return derivedType;
+    }
+
+    /**
+     * Get the referenced type.
+     *
+     * @param derivedType the referenced type.
+     */
+    @SuppressWarnings("rawtypes")
+    public void setDerivedType(YangType derivedType) {
+        this.derivedType = derivedType;
+    }
+
+    /**
+     * Get the unit.
+     *
+     * @return the units
+     */
+    public String getUnits() {
+        return units;
+    }
+
+    /**
+     * Set the unit.
+     *
+     * @param units the units to set
+     */
+    public void setUnits(String units) {
+        this.units = units;
+    }
+
+    /**
+     * Returns the type of the data.
+     *
+     * @return returns TYPEDEF_DATA
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.TYPEDEF_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getName()
+     */
+    @Override
+    public String getName() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setName(java.lang.String)
+     */
+    @Override
+    public void setName(String name) {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeEntry()
+     */
+    public void generateJavaCodeEntry() {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeExit()
+     */
+    public void generateJavaCodeExit() {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getPackage()
+     */
+    @Override
+    public String getPackage() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setPackage(java.lang.String)
+     */
+    @Override
+    public void setPackage(String pkg) {
+        // TODO Auto-generated method stub
+
+    }
+}

+/*
+ * 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.datamodel;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.ParsableDataType;
+
+/*-
+ * Reference RFC 6020.
+ *
+ * The "uses" statement is used to reference a "grouping" definition. It takes
+ * one argument, which is the name of the grouping.
+ *
+ * The effect of a "uses" reference to a grouping is that the nodes defined by
+ * the grouping are copied into the current schema tree, and then updated
+ * according to the "refine" and "augment" statements.
+ *
+ * The identifiers defined in the grouping are not bound to a namespace until
+ * the contents of the grouping are added to the schema tree via a "uses"
+ * statement that does not appear inside a "grouping" statement, at which point
+ * they are bound to the namespace of the current module.
+ *
+ * The uses's sub-statements
+ *
+ *                +--------------+---------+-------------+------------------+
+ *                | substatement | section | cardinality |data model mapping|
+ *                +--------------+---------+-------------+------------------+
+ *                | augment      | 7.15    | 0..1        | -child nodes     |
+ *                | description  | 7.19.3  | 0..1        | -string          |
+ *                | if-feature   | 7.18.2  | 0..n        | -TODO            |
+ *                | refine       | 7.12.2  | 0..1        | -TODO            |
+ *                | reference    | 7.19.4  | 0..1        | -string          |
+ *                | status       | 7.19.2  | 0..1        | -YangStatus      |
+ *                | when         | 7.19.5  | 0..1        | -TODO            |
+ *                +--------------+---------+-------------+------------------+
+ */
+/**
+ * Data model node to maintain information defined in YANG uses.
+ *
+ */
+public class YangUses extends YangNode implements YangCommonInfo, Parsable {
+
+    /**
+     * Name.
+     */
+    private String name;
+
+    /**
+     * referred group.
+     */
+    private YangGrouping refGroup;
+
+    /**
+     * description.
+     */
+    private String description;
+
+    /**
+     * YANG reference.
+     */
+    private String reference;
+
+    /**
+     * Status.
+     */
+    private YangStatusType status;
+
+    /**
+     * Create an YANG uses node.
+     */
+    public YangUses() {
+        super(YangNodeType.USES_NODE);
+    }
+
+    /**
+     * Get the name.
+     *
+     * @return the name.
+     */
+    public String getRefGroupingName() {
+        return name;
+    }
+
+    /**
+     * Set the name.
+     *
+     * @param refGroupingName the referred grouping name to set
+     */
+    public void setRefGroupingName(String refGroupingName) {
+        name = refGroupingName;
+    }
+
+    /**
+     * Get the referred group.
+     *
+     * @return the referred group.
+     */
+    public YangGrouping getRefGroup() {
+        return refGroup;
+    }
+
+    /**
+     * Set the referred group.
+     *
+     * @param refGroup the referred group.
+     */
+    public void setRefGroup(YangGrouping refGroup) {
+        this.refGroup = refGroup;
+    }
+
+    /**
+     * Get the description.
+     *
+     * @return the description.
+     */
+    public String getDescription() {
+        return description;
+    }
+
+    /**
+     * Set the description.
+     *
+     * @param description set the description.
+     */
+    public void setDescription(String description) {
+        this.description = description;
+    }
+
+    /**
+     * Get the textual reference.
+     *
+     * @return the reference.
+     */
+    public String getReference() {
+        return reference;
+    }
+
+    /**
+     * Set the textual reference.
+     *
+     * @param reference the reference to set.
+     */
+    public void setReference(String reference) {
+        this.reference = reference;
+    }
+
+    /**
+     * Get the status.
+     *
+     * @return the status.
+     */
+    public YangStatusType getStatus() {
+        return status;
+    }
+
+    /**
+     * Set the status.
+     *
+     * @param status the status to set.
+     */
+    public void setStatus(YangStatusType status) {
+        this.status = status;
+    }
+
+    /**
+     * Returns the type of the data.
+     *
+     * @return returns USES_DATA.
+     */
+    public ParsableDataType getParsableDataType() {
+        return ParsableDataType.USES_DATA;
+    }
+
+    /**
+     * Validate the data on entering the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnEntry() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /**
+     * Validate the data on exiting the corresponding parse tree node.
+     *
+     * @throws DataModelException a violation of data model rules.
+     */
+    public void validateDataOnExit() throws DataModelException {
+        // TODO auto-generated method stub, to be implemented by parser
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getName()
+     */
+    @Override
+    public String getName() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setName(java.lang.String)
+     */
+    @Override
+    public void setName(String name) {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeEntry()
+     */
+    public void generateJavaCodeEntry() {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.translator.CodeGenerator#generateJavaCodeExit()
+     */
+    public void generateJavaCodeExit() {
+        // TODO Auto-generated method stub
+
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#getPackage()
+     */
+    @Override
+    public String getPackage() {
+        // TODO Auto-generated method stub
+        return null;
+    }
+
+    /* (non-Javadoc)
+     * @see org.onosproject.yangutils.datamodel.YangNode#setPackage(java.lang.String)
+     */
+    @Override
+    public void setPackage(String pkg) {
+        // TODO Auto-generated method stub
+
+    }
+}