[REEF-1902] Use external executor and Runnable in MultiAsyncToSync

• Type: Sub-task
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 0.17
• Component/s: Wake
• Labels: asynchronous tests wake
• Assignee: Sergiy Matusevych
• Reporter: Sergiy Matusevych
• Created: 18/Oct/17 22:24
• Updated: 24/Oct/17 01:26
• Resolved: 24/Oct/17 01:26

Description

MultiAsyncToSync class takes a FutureTask<> as input, but only calls its .run() method. That is, we can simplify the interface and make it accept Runnable. This change is packward-compatible, as FutureTask implements Runnable. We should also allow MultiAsyncToSync to run tasks indirectly using the executor service, and update the unit tests accordingly.