diff --git a/core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala b/core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala
index 7a76c2f97e8d7..30bc1382fb021 100644
--- a/core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala
+++ b/core/src/main/scala/org/apache/spark/shuffle/IndexShuffleBlockResolver.scala
@@ -57,11 +57,23 @@ import org.apache.spark.util.collection.OpenHashSet
 private[spark] class IndexShuffleBlockResolver(
     conf: SparkConf,
     // var for testing
-    var _blockManager: BlockManager = null,
-    val taskIdMapsForShuffle: JMap[Int, OpenHashSet[Long]] = Collections.emptyMap())
+    var _blockManager: BlockManager,
+    val taskIdMapsForShuffle: JMap[Int, OpenHashSet[Long]])
   extends ShuffleBlockResolver
   with Logging with MigratableResolver {
 
+  def this(conf: SparkConf) = {
+    this(conf, null, Collections.emptyMap())
+  }
+
+  def this(conf: SparkConf, _blockManager: BlockManager) = {
+    this(conf, _blockManager, Collections.emptyMap())
+  }
+
+  def this(conf: SparkConf, taskIdMapsForShuffle: JMap[Int, OpenHashSet[Long]]) = {
+    this(conf, null, taskIdMapsForShuffle)
+  }
+
   private lazy val blockManager = Option(_blockManager).getOrElse(SparkEnv.get.blockManager)
 
   private val transportConf = {