Right now they are safe because the caller also calls synchronized when using them. This is to avoid copying objects. It's probably a bad design. If you want to refactor them, PR is welcome.
On Mon, Jun 26, 2017 at 2:27 AM, Oleksandr Vayda <oleksandr.va...@gmail.com> wrote: > Hi all, > > Reading the source code of the org.apache.spark.sql.execution.ui. > SQLListener, specifically this place - https://github.com/apache/ > spark/blob/master/sql/core/src/main/scala/org/apache/ > spark/sql/execution/ui/SQLListener.scala#L328 > > def getFailedExecutions: Seq[SQLExecutionUIData] = synchronized { > failedExecutions > } > def getCompletedExecutions: Seq[SQLExecutionUIData] = synchronized { > completedExecutions > } > I believe the synchronized block is used here incorrectly. If I get it > right the main purpose here is to synchronize access to the mutable > collections from the UI (read) and the event bus (read/write) threads. But > in the current implementation the "synchronized" blocks return bare > references to mutable collections and in fact nothing gets synchronized. > Is it a bug? > > Sincerely yours, > Oleksandr Vayda > > mobile: +420 604 113 056 <+420%20604%20113%20056> >
