diff --git a/core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala b/core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala
index 533c9847661b6..70b685dabe663 100644
--- a/core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala
+++ b/core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala
@@ -17,7 +17,7 @@
 
 package org.apache.spark.rpc.netty
 
-import java.util.concurrent.{ThreadPoolExecutor, ConcurrentHashMap, LinkedBlockingQueue, TimeUnit}
+import java.util.concurrent.{ThreadPoolExecutor, ConcurrentHashMap, ConcurrentMap, LinkedBlockingQueue, TimeUnit}
 import javax.annotation.concurrent.GuardedBy
 
 import scala.collection.JavaConverters._
@@ -41,8 +41,8 @@ private[netty] class Dispatcher(nettyEnv: NettyRpcEnv) extends Logging {
     val inbox = new Inbox(ref, endpoint)
   }
 
-  private val endpoints = new ConcurrentHashMap[String, EndpointData]
-  private val endpointRefs = new ConcurrentHashMap[RpcEndpoint, RpcEndpointRef]
+  private val endpoints: ConcurrentMap[String, EndpointData] = new ConcurrentHashMap[String, EndpointData]
+  private val endpointRefs: ConcurrentMap[RpcEndpoint, RpcEndpointRef] = new ConcurrentHashMap[RpcEndpoint, RpcEndpointRef]
 
   // Track the receivers whose inboxes may contain messages.
   private val receivers = new LinkedBlockingQueue[EndpointData]
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Catalog.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Catalog.scala
index 8f4ce74a2ea38..fcde8f1dcd261 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Catalog.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/Catalog.scala
@@ -17,7 +17,7 @@
 
 package org.apache.spark.sql.catalyst.analysis
 
-import java.util.concurrent.ConcurrentHashMap
+import java.util.concurrent.{ConcurrentHashMap, ConcurrentMap}
 
 import scala.collection.JavaConverters._
 import scala.collection.mutable
@@ -80,7 +80,7 @@ trait Catalog {
 }
 
 class SimpleCatalog(val conf: CatalystConf) extends Catalog {
-  private[this] val tables = new ConcurrentHashMap[String, LogicalPlan]
+  private[this] val tables: ConcurrentMap[String, LogicalPlan] = new ConcurrentHashMap[String, LogicalPlan]
 
   override def registerTable(tableIdent: TableIdentifier, plan: LogicalPlan): Unit = {
     tables.put(getTableName(tableIdent), plan)