diff --git a/pom.xml b/pom.xml
index 931f4c7..029155b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -9,19 +9,24 @@
     <version>1.0</version>
 
     <properties>
-        <scala.version>2.10.2</scala.version>
+        <scala.version>2.12.0</scala.version>
         <junit.version>4.11</junit.version>
     </properties>
 
     <dependencies>
         <dependency>
             <groupId>org.specs2</groupId>
-            <artifactId>specs2_2.10</artifactId>
-            <version>2.0</version>
+            <artifactId>specs2-core_2.12</artifactId>
+            <version>3.8.6</version>
             <scope>test</scope>
         </dependency>
 
-
+        <dependency>
+            <groupId>org.specs2</groupId>
+            <artifactId>specs2-junit_2.12</artifactId>
+            <version>3.8.6</version>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
@@ -32,23 +37,25 @@
         <dependency>
             <groupId>org.scala-lang</groupId>
             <artifactId>scala-compiler</artifactId>
-            <version>2.10.2</version>
+            <version>2.12.0</version>
         </dependency>
 
 
         <dependency>
             <groupId>org.mongodb</groupId>
             <artifactId>mongo-java-driver</artifactId>
-            <version>2.10.1</version>
+            <version>3.12.1</version>
+            <!--<version>3.12.1</version>-->
         </dependency>
 
 
         <dependency>
             <groupId>org.mongodb</groupId>
-            <artifactId>casbah-core_2.10</artifactId>
-            <version>2.6.1</version>
+            <artifactId>casbah-core_2.12</artifactId>
+            <version>3.1.1</version>
         </dependency>
 
+
     </dependencies>
     <build>
         <finalName>${project.artifactId}</finalName>
@@ -58,19 +65,22 @@
             <plugin>
                 <groupId>net.alchim31.maven</groupId>
                 <artifactId>scala-maven-plugin</artifactId>
+                <version>4.3.1</version>
             </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.8.1</version>
             </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-source-plugin</artifactId>
+                <version>3.2.1</version>
             </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
-                <version>2.15</version>
+                <version>2.22.2</version>
                 <configuration>
                     <includes>
                         <include>**/*Suite.class</include>
@@ -81,27 +91,6 @@
                     </includes>
                 </configuration>
             </plugin>
-            <plugin>
-                <groupId>org.scala-tools</groupId>
-                <artifactId>maven-scala-plugin</artifactId>
-                <executions>
-                    <execution>
-                        <id>scala-compile-first</id>
-                        <phase>process-resources</phase>
-                        <goals>
-                            <goal>add-source</goal>
-                            <goal>compile</goal>
-                        </goals>
-                    </execution>
-                    <execution>
-                        <id>scala-test-compile</id>
-                        <phase>process-test-resources</phase>
-                        <goals>
-                            <goal>testCompile</goal>
-                        </goals>
-                    </execution>
-                </executions>
-            </plugin>
         </plugins>
     </build>
 
diff --git a/src/main/scala/com/ee/dynamicmongoquery/MongoQuery.scala b/src/main/scala/com/ee/dynamicmongoquery/MongoQuery.scala
index 617582f..ad4a8d1 100644
--- a/src/main/scala/com/ee/dynamicmongoquery/MongoQuery.scala
+++ b/src/main/scala/com/ee/dynamicmongoquery/MongoQuery.scala
@@ -50,8 +50,8 @@ class MongoQuery(val queryTypes: List[Query], val collectionName: String) {
 
   protected def executeAggregate(aggregationQuery: AggregateQuery, collection: DBCollection): Array[DBObject] = {
     val aggregationPipeline = aggregationQuery.aggregationPipeline
-    var aggregateOP = collection.aggregate(aggregationPipeline.head, aggregationPipeline.tail: _*)
-    aggregateOP.results().toTraversable.toArray
+    var cursor = collection.aggregate(aggregationPipeline, AggregationOptions.builder().batchSize(100).allowDiskUse(true).build())
+    cursor.toArray
   }
 
 
@@ -78,5 +78,11 @@ class MongoQuery(val queryTypes: List[Query], val collectionName: String) {
       case _ => false
     }
   }
+  // Overriding toString method
+  override def toString() : String = {
+
+    return "[MongoQuery : " +  this.collectionName +
+      ", Types:  = " + this.queryTypes+"]";
+  }
 }
 
diff --git a/src/main/scala/com/ee/dynamicmongoquery/PlaceholderLookup.scala b/src/main/scala/com/ee/dynamicmongoquery/PlaceholderLookup.scala
index 29b061e..a18a284 100644
--- a/src/main/scala/com/ee/dynamicmongoquery/PlaceholderLookup.scala
+++ b/src/main/scala/com/ee/dynamicmongoquery/PlaceholderLookup.scala
@@ -14,7 +14,7 @@ class PlaceholderLookup(params: Map[String, String]) {
         }
         case s: String => {
           val resolvedValue = placeholderResolver.resolve(s)
-          basicDBObject.put(key, resolvedValue)
+          basicDBObject.put(key, resolvedValue.asInstanceOf[AnyRef])
         }
         case _ => {
           basicDBObject.put(key, value)
diff --git a/src/test/scala/com/ee/dynamicmongoquery/IntegrationTest.scala b/src/test/scala/com/ee/dynamicmongoquery/IntegrationTest.scala
index e7b7347..20d164f 100644
--- a/src/test/scala/com/ee/dynamicmongoquery/IntegrationTest.scala
+++ b/src/test/scala/com/ee/dynamicmongoquery/IntegrationTest.scala
@@ -1,21 +1,22 @@
 package com.ee.dynamicmongoquery
 
-import com.mongodb.casbah.{MongoConnection, MongoCollection}
+import com.mongodb.casbah.{Imports, MongoClient, MongoCollection, MongoConnection}
 import com.mongodb.util.JSON
-import com.mongodb.{BasicDBList, BasicDBObject}
+import com.mongodb.{BasicDBList, BasicDBObject, DBCollection}
 import org.specs2.mutable.{BeforeAfter, Specification}
 import org.specs2.matcher.MatchResult
+import org.specs2.specification.BeforeAfterEach
 
 
-class IntegrationTest extends Specification {
+class IntegrationTest extends Specification with BeforeAfterEach  {
 
-  lazy val mongoConn = MongoConnection()
-  lazy val mongoDB = mongoConn("dynamic-query-test-db")
-  lazy val userCollection: MongoCollection = mongoDB("users")
+  lazy val mongoConn = MongoClient()
+  lazy val mongoDB = mongoConn.getDB("dynamic-query-test-db")
+  lazy val userCollection: DBCollection = mongoDB.getCollection("users")
 
   lazy val parser: MongoQueryParser = new MongoQueryParser()
+  sequential
 
-  implicit val myContext = new BeforeAfter {
 
     def clearCollections {
       userCollection.drop()
@@ -34,7 +35,6 @@ class IntegrationTest extends Specification {
     def after = {
       clearCollections
     }
-  }
 
 
   def readJsonFile(config: String): String = {
diff --git a/src/test/scala/com/ee/dynamicmongoquery/MongoQueryParserTest.scala b/src/test/scala/com/ee/dynamicmongoquery/MongoQueryParserTest.scala
index a1aafe9..f604da8 100644
--- a/src/test/scala/com/ee/dynamicmongoquery/MongoQueryParserTest.scala
+++ b/src/test/scala/com/ee/dynamicmongoquery/MongoQueryParserTest.scala
@@ -58,7 +58,7 @@ class MongoQueryParserTest extends Specification {
 
   "find query with params and datatypes" in {
     //Given
-    val query: String = "db.users.find({'name':'name#String', 'rank' : 'givenRank#Integer' , 'employed':'isEmployed#Boolean', 'salary':'sal#Long','weight' :'weight#Double'})"
+    val query: String = "db.users.find({'name':'name#String', 'rank' : 'givenRank#Integer' , 'employed':'isEmployed#Boolean', 'salary':'sal#Integer','weight' :'weight#Double'})"
     val params: Map[String, String] = Map("name" -> "leena", "givenRank" -> "5", "isEmployed" -> "true", "sal" -> "1000", "weight" -> "2.5")
     val lookup: PlaceholderLookup = new PlaceholderLookup(params)
 
@@ -151,7 +151,7 @@ class MongoQueryParserTest extends Specification {
 
   "aggregation query " in {
     //Given
-    val query: String = "db.users.aggregate([{'$match':{'salary' : {$gte:'from#Long',$lte:'to#Long'}}}, { $group: {_id:'$role', 'role': {$sum:  '$age' }  }  }, {  '$sort': {  'age': -1 } },   {  '$limit': 5 }])"
+    val query: String = "db.users.aggregate([{'$match':{'salary' : {$gte:'from#Integer',$lte:'to#Integer'}}}, { $group: {_id:'$role', 'role': {$sum:  '$age' }  }  }, {  '$sort': {  'age': -1 } },   {  '$limit': 5 }])"
     val params: Map[String, String] = Map("from"->"1000","to" -> "2000")
     val lookup: PlaceholderLookup = new PlaceholderLookup(params)
 
@@ -166,7 +166,7 @@ class MongoQueryParserTest extends Specification {
 
   "aggregation query without array " in {
     //Given
-    val query: String = "db.users.aggregate(  {  '$match':{'salary' : {$gte:'from#Long',$lte:'to#Long'}}}, { $group: {_id:'$role', 'role': {$sum:  '$age' }  }  }, {  '$sort': {  'age': -1 } },   {  '$limit': 5  }  )"
+    val query: String = "db.users.aggregate(  {  '$match':{'salary' : {$gte:'from#Integer',$lte:'to#Integer'}}}, { $group: {_id:'$role', 'role': {$sum:  '$age' }  }  }, {  '$sort': {  'age': -1 } },   {  '$limit': 5  }  )"
     val params: Map[String, String] = Map("from"->"1000","to" -> "2000")
     val lookup: PlaceholderLookup = new PlaceholderLookup(params)
 
diff --git a/src/test/scala/com/ee/dynamicmongoquery/PlaceholderLookupTest.scala b/src/test/scala/com/ee/dynamicmongoquery/PlaceholderLookupTest.scala
index e251e22..061ff10 100644
--- a/src/test/scala/com/ee/dynamicmongoquery/PlaceholderLookupTest.scala
+++ b/src/test/scala/com/ee/dynamicmongoquery/PlaceholderLookupTest.scala
@@ -13,7 +13,7 @@ class PlaceholderLookupTest extends Specification {
     val lookup: PlaceholderLookup = new PlaceholderLookup(params)
 
     val address = new BasicDBObject()
-    address.put("lane", 5)
+    address.put("lane", 5:Integer)
     address.put("city", "Pune")
     address.put("country", "country")
     address.put("zipcode", "zip#Integer")
@@ -23,10 +23,10 @@ class PlaceholderLookupTest extends Specification {
     person.put("dontreplace", "dontreplace#Long")
 
     val expectedAddress = new BasicDBObject()
-    expectedAddress.put("lane", 5)
+    expectedAddress.put("lane", 5:Integer)
     expectedAddress.put("city", "Pune")
     expectedAddress.put("country", "India")
-    expectedAddress.put("zipcode", 411037)
+    expectedAddress.put("zipcode", 411037:Integer)
     val expectedPerson = new BasicDBObject()
     expectedPerson.put("name", "leena")
     expectedPerson.put("address", address)
diff --git a/src/test/scala/com/ee/dynamicmongoquery/QueryTest.scala b/src/test/scala/com/ee/dynamicmongoquery/QueryTest.scala
index ffe36c8..e8416fd 100644
--- a/src/test/scala/com/ee/dynamicmongoquery/QueryTest.scala
+++ b/src/test/scala/com/ee/dynamicmongoquery/QueryTest.scala
@@ -2,10 +2,14 @@ package com.ee.dynamicmongoquery
 
 import org.specs2.mutable.Specification
 import com.mongodb.BasicDBObject
+
 import collection.JavaConversions._
 import org.junit.runner.RunWith
 import org.specs2.runner.JUnitRunner
 
+import scala.collection.immutable.SortedMap
+import scala.collection.mutable
+
 @RunWith(classOf[JUnitRunner])
 class QueryTest extends Specification {
   "Find Queries" should {
@@ -62,22 +66,7 @@ class QueryTest extends Specification {
       val findQuery = FindQuery(query, lookup)
 
       //Then
-      val criteriaMap = Map("name" -> "leena", "rank" -> 5, "employed" -> true, "salary" -> 1000, "weight" -> 2.5)
-      findQuery.criteria === new BasicDBObject(criteriaMap)
-      findQuery.projection === new BasicDBObject()
-    }
-
-    "find query with params and datatypes" in {
-      //Given
-      val query: String = "{'name':'name#String', 'rank' : 'givenRank#Integer' , 'employed':'isEmployed#Boolean', 'salary':'sal#Long','weight' :'weight#Double'}"
-      val params: Map[String, String] = Map("name" -> "leena", "givenRank" -> "5", "isEmployed" -> "true", "sal" -> "1000", "weight" -> "2.5")
-      val lookup: PlaceholderLookup = new PlaceholderLookup(params)
-
-      //When
-      val findQuery = FindQuery(query, lookup)
-
-      //Then
-      val criteriaMap = Map("name" -> "leena", "rank" -> 5, "employed" -> true, "salary" -> 1000, "weight" -> 2.5)
+      val criteriaMap = mutable.LinkedHashMap("name" -> "leena", "rank" -> 5, "employed" -> true, "salary" -> 1000l, "weight" -> 2.5)
       findQuery.criteria === new BasicDBObject(criteriaMap)
       findQuery.projection === new BasicDBObject()
     }