[SNAp-2084] Added a check to set Snappy UMM if found in classpath.

core/src/main/scala/org/apache/spark/SparkSnappyUtils.scala

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2017 SnappyData, Inc. All rights reserved.
+ *
+ * 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. See accompanying
+ * LICENSE file.
+ */
+package org.apache.spark
+
+import org.apache.spark.memory.MemoryManager
+import org.apache.spark.util.Utils
+
+
+object SparkSnappyUtils {
+
+  val SNAPPY_UNIFIED_MEMORY_MANAGER_CLASS = "org.apache.spark.memory.SnappyUnifiedMemoryManager"
+
+  def loadSnappyManager(conf: SparkConf, numUsableCores: Int): Option[MemoryManager] = {
+    try {
+      Some(Utils.classForName(SNAPPY_UNIFIED_MEMORY_MANAGER_CLASS)
+          .getConstructor(classOf[SparkConf], classOf[Int])
+          .newInstance(conf, Int.box(numUsableCores))
+          .asInstanceOf[MemoryManager])
+    } catch {
+      case ex: ClassNotFoundException => None
+    }
+  }
+
+}