Update comments.

apache · Feb 3, 2018 · 52e6f19 · 52e6f19
1 parent 234a637
commit 52e6f19
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/DriverRegistry.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/jdbc/DriverRegistry.scala
@@ -32,7 +32,11 @@ import org.apache.spark.util.Utils
  */
 object DriverRegistry extends Logging {
 
-  // Initialize DriverManager first to prevent potential deadlocks between DriverManager and Driver
+  /**
+   * Load DriverManager first to avoid any race condition between
+   * DriverManager static initialization block and specific driver class's
+   * static initialization block. e.g. PhoenixDriver
+   */
   DriverManager.getDrivers
 
   private val wrapperMap: mutable.Map[String, DriverWrapper] = mutable.Map.empty