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public/biopet-framework/src/main/scala/nl/lumc/sasc/biopet/utils/ConfigUtils.scala

@@ -58,10 +58,10 @@ object ConfigUtils extends Logging {
    * @param path Nested path to get from map
    * @return Nested map
    */
-  def getMapFromPath(map: Map[String, Any], path: List[String]): Map[String, Any] = {
-    val value = getValueFromPath(map, path) getOrElse { return null }
+  def getMapFromPath(map: Map[String, Any], path: List[String]): Option[Map[String, Any]] = {
+    val value = getValueFromPath(map, path) getOrElse { return None }
     value match {
-      case m: Map[_, _] => m.asInstanceOf[Map[String, Any]]
+      case m: Map[_, _] => Some(m.asInstanceOf[Map[String, Any]])
       case _            => throw new IllegalStateException("Value is not a map: " + value)
     }
   }

public/biopet-framework/src/test/scala/nl/lumc/sasc/biopet/utils/ConfigUtilsTest.scala

@@ -26,8 +26,8 @@ class ConfigUtilsTest extends TestNGSuite with MockitoSugar with Matchers {
   }
 
   @Test def testGetMapFromPath: Unit = {
-    getMapFromPath(map1, List("dummy")) shouldBe Map("dummy" -> 1)
-    getMapFromPath(map1, List("nested3", "nested2", "nested1")) shouldBe Map("dummy" -> 1)
+    getMapFromPath(map1, List("dummy")) shouldBe Some(Map("dummy" -> 1))
+    getMapFromPath(map1, List("nested3", "nested2", "nested1")) shouldBe Some(Map("dummy" -> 1))
     intercept[IllegalStateException] {
       getMapFromPath(map1, List("dummy", "dummy"))
     }