diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/exception/TranslatorException.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/exception/TranslatorException.java
new file mode 100644
index 0000000..218e24d
--- /dev/null
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/exception/TranslatorException.java
@@ -0,0 +1,79 @@
+/*
+ * 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.translator.exception;
+
+/**
+ * Provides custom translator exception for translator's operations.
+ */
+public class TranslatorException extends RuntimeException {
+
+    private static final long serialVersionUID = 20160311L;
+    private String fileName;
+
+    /**
+     * Create a new translator exception.
+     */
+    public TranslatorException() {
+        super();
+    }
+
+    /**
+     * Creates a new translator exception with given message.
+     *
+     * @param message the detail of exception in string
+     */
+    public TranslatorException(String message) {
+        super(message);
+    }
+
+    /**
+     * Creates a new translator exception from given message and cause.
+     *
+     * @param message the detail of exception in string
+     * @param cause underlying cause of the error
+     */
+    public TranslatorException(final String message, final Throwable cause) {
+        super(message, cause);
+    }
+
+    /**
+     * Creates a new translator exception from cause.
+     *
+     * @param cause underlying cause of the error
+     */
+    public TranslatorException(final Throwable cause) {
+        super(cause);
+    }
+
+    /**
+     * Returns generated file name for the exception.
+     *
+     * @return generated file name for the exception
+     */
+    public String getFileName() {
+        return this.fileName;
+    }
+
+    /**
+     * Sets file name in translator exception.
+     *
+     * @param fileName generated file name
+     */
+    public void setFileName(String fileName) {
+        this.fileName = fileName;
+    }
+}
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/exception/package-info.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/exception/package-info.java
new file mode 100644
index 0000000..7432328
--- /dev/null
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/exception/package-info.java
@@ -0,0 +1,20 @@
+/*
+ * 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.
+ */
+
+/**
+ * Custom exception for translator.
+ */
+package org.onosproject.yangutils.translator.exception;
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/tojava/utils/JavaIdentifierSyntax.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/tojava/utils/JavaIdentifierSyntax.java
index 00e953b..dd543ca 100644
--- a/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/tojava/utils/JavaIdentifierSyntax.java
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/tojava/utils/JavaIdentifierSyntax.java
@@ -18,6 +18,7 @@
 
 import java.util.ArrayList;
 
+import org.onosproject.yangutils.translator.exception.TranslatorException;
 import org.onosproject.yangutils.utils.UtilConstants;
 
 /**
@@ -25,8 +26,15 @@
  */
 public final class JavaIdentifierSyntax {
 
+    private static final int MAX_MONTHS = 12;
+    private static final int MAX_DAYS = 31;
+    private static final int INDEX_ZERO = 0;
+    private static final int INDEX_ONE = 1;
+    private static final int INDEX_TWO = 2;
+    private static final int INDEX_THREE = 3;
+
     /**
-     * Util class, with static functions only.
+     * Default constructor.
      */
     private JavaIdentifierSyntax() {
     }
@@ -71,9 +79,9 @@
      */
     public static String getPkgFromNameSpace(String nameSpace) {
         ArrayList<String> pkgArr = new ArrayList<String>();
-        nameSpace = nameSpace.replace("\"", "");
-
-        String[] nameSpaceArr = nameSpace.split(UtilConstants.COLAN);
+        nameSpace = nameSpace.replace(UtilConstants.QUOTES, UtilConstants.EMPTY_STRING);
+        String properNameSpace = nameSpace.replaceAll(UtilConstants.REGEX_WITH_SPECIAL_CHAR, UtilConstants.COLAN);
+        String[] nameSpaceArr = properNameSpace.split(UtilConstants.COLAN);
 
         for (String nameSpaceString : nameSpaceArr) {
             pkgArr.add(nameSpaceString);
@@ -86,19 +94,31 @@
      *
      * @param date YANG module revision
      * @return revision string
+     * @throws TranslatorException when date is invalid.
      */
-    public static String getYangRevisionStr(String date) {
+    public static String getYangRevisionStr(String date) throws TranslatorException {
         String[] revisionArr = date.split(UtilConstants.HYPHEN);
 
         String rev = "rev";
-        for (String element : revisionArr) {
-            Integer val = Integer.parseInt(element);
-            if (val < 10) {
-                rev = rev + "0";
+        String year = revisionArr[INDEX_ZERO];
+        char[] yearBytes = year.toCharArray();
+        rev = rev + yearBytes[INDEX_TWO] + yearBytes[INDEX_THREE];
+
+        if ((Integer.parseInt(revisionArr[INDEX_ONE]) <= MAX_MONTHS)
+                && Integer.parseInt(revisionArr[INDEX_TWO]) <= MAX_DAYS) {
+            for (int i = INDEX_ONE; i < revisionArr.length; i++) {
+
+                Integer val = Integer.parseInt(revisionArr[i]);
+                if (val < 10) {
+                    rev = rev + "0";
+                }
+                rev = rev + val;
             }
-            rev = rev + val;
+
+            return rev;
+        } else {
+            throw new TranslatorException("Date in revision is not proper: " + date);
         }
-        return rev;
     }
 
     /**
@@ -109,10 +129,14 @@
      */
     public static String getPkgFrmArr(ArrayList<String> pkgArr) {
 
-        String pkg = "";
+        String pkg = UtilConstants.EMPTY_STRING;
         int size = pkgArr.size();
         int i = 0;
         for (String member : pkgArr) {
+            boolean presenceOfKeyword = UtilConstants.JAVA_KEY_WORDS.contains(member);
+            if (presenceOfKeyword || (member.matches(UtilConstants.REGEX_FOR_FIRST_DIGIT))) {
+                member = UtilConstants.UNDER_SCORE + member;
+            }
             pkg = pkg + member;
             if (i != size - 1) {
                 pkg = pkg + UtilConstants.PERIOD;
@@ -174,4 +198,14 @@
     public static String getCaptialCase(String yangIdentifier) {
         return yangIdentifier.substring(0, 1).toUpperCase() + yangIdentifier.substring(1);
     }
+
+    /**
+     * Translate the YANG identifier name to java identifier with first letter in small.
+     *
+     * @param yangIdentifier identifier in YANG file.
+     * @return corresponding java identifier
+     */
+    public static String getLowerCase(String yangIdentifier) {
+        return yangIdentifier.substring(0, 1).toLowerCase() + yangIdentifier.substring(1);
+    }
 }
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/utils/UtilConstants.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/utils/UtilConstants.java
index f596bf8..63c1fe7 100644
--- a/utils/yangutils/src/main/java/org/onosproject/yangutils/utils/UtilConstants.java
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/utils/UtilConstants.java
@@ -16,6 +16,9 @@
 
 package org.onosproject.yangutils.utils;
 
+import java.util.Arrays;
+import java.util.List;
+
 /**
  * Provides utility constants while generating java files.
  */
@@ -41,6 +44,8 @@
     public static final String JAVA_DOC_RETURN = " * @return ";
     public static final String JAVA_DOC_THROWS = " * @throws ";
     public static final String JAVA_DOC_SETTERS = " * Returns the builder object of ";
+    public static final String JAVA_DOC_OF = " * Returns the object of ";
+    public static final String JAVA_DOC_SETTERS_COMMON = " * Sets the value of ";
     public static final String JAVA_DOC_GETTERS = " * Returns the attribute ";
     public static final String JAVA_DOC_DEFAULT_CONSTRUCTOR = " * Default Constructor.\n";
     public static final String JAVA_DOC_CONSTRUCTOR = " * Construct the object of ";
@@ -51,9 +56,11 @@
      * Basic requirements.
      */
     public static final String NEW_LINE = "\n";
+    public static final String EMPTY_STRING = "";
     public static final String NEW_LINE_ESTRIC = " *\n";
     public static final String PERIOD = ".";
     public static final String COLAN = ":";
+    public static final String UNDER_SCORE = "_";
     public static final String SEMI_COLAN = ";";
     public static final String HYPHEN = "-";
     public static final String SPACE = " ";
@@ -63,6 +70,25 @@
     public static final String ADD = "+";
     public static final String ASTERISK = "*";
     public static final String AT = "@";
+    public static final String QUOTES = "\"";
+    public static final String AND = "&";
+    public static final String COMMA = ",";
+    public static final String ADD_STRING = "add";
+    public static final String CHECK_NOT_NULL_STRING = "checkNotNull";
+    public static final String HASH_CODE_STRING = "hashCode";
+    public static final String EQUALS_STRING = "equals";
+    public static final String OBJECT_STRING = "Object";
+    public static final String INSTANCE_OF = " instanceof ";
+
+    public static final String VALUE = "value";
+
+    public static final String IF = "if";
+    public static final String FOR = "for";
+    public static final String WHILE = "while";
+    public static final String OF = "of";
+
+    public static final String TRUE = "true";
+    public static final String FALSE = "false";
 
     /**
      * For brackets.
@@ -193,7 +219,23 @@
     public static final String DOUBLE_WRAPPER = "Double";
 
     /**
-     * For idenifiers.
+     * List of keywords in java, this is used for checking if the input does not contain these keywords.
+     */
+    public static final List JAVA_KEY_WORDS = Arrays.asList("abstract", "assert", "boolean", "break", "byte", "case",
+            "catch", "char", "class", "const", "continue", "default", "do", "double", "else", "extends", "false",
+            "final", "finally", "float", "for", "goto", "if", "implements", "import", "instanceof", "int", "interface",
+            "long", "native", "new", "null", "package", "private", "protected", "public", "return", "short", "static",
+            "strictfp", "super", "switch", "synchronized", "this", "throw", "throws", "transient", "true", "try",
+            "void", "volatile", "while");
+
+    /**
+     * Defining regular expression.
+     */
+    public static final String REGEX_WITH_SPECIAL_CHAR = "[ : / - @ $ # ' * + , ; = ]+";
+    public static final String REGEX_FOR_FIRST_DIGIT = "\\d.*";
+
+    /**
+     * For identifiers.
      */
     public static final String CLASS = "class";
     public static final String BUILDER = "Builder";
@@ -218,7 +260,9 @@
     /**
      * For collections.
      */
-    public static final String COLLECTION_IMPORTS = "import java.util.";
+    public static final String COLLECTION_IMPORTS = "java.util";
+    public static final String MORE_OBJECT_IMPORT = "import com.google.common.base.MoreObjects;\n";
+    public static final String JAVA_UTIL_OBJECTS_IMPORT = "import java.util.Objects;\n";
     public static final String ABSTRACT_COLLECTION = "AbstractCollection";
 
     public static final String LIST = "List";