[JEXL-115] Add support for asynchronous script execution and cancellation

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.1
• Assignee: Henri Biestro
• Reporter: Henri Biestro
• Created: 13/Jul/11 20:26
• Updated: 14/Dec/11 09:29
• Resolved: 17/Jul/11 18:45

Description

WHY:
To allow proper sandboxing and let users run their own script, it is necessary to control the time a script is allowed to run and avoid runaway executions (for instance while(true); ).
WHAT:
Support for asynchronuous execution is usually based on Runnable/Callable/Future and Thread interruption. The Callable interface seems the most versatile so a method to transform a Script into a Callable seems in order. Thread interruption is in most cases an indication that must be checked (besides locking methods) somehow.
HOW:
Creating a Callable from a Script, Context (and arguments) is straightforward. Checking thread interruption can be performed in the Interpreter loop at "key" points namely getting/setting properties, calling methods/functions, resolving identifiers and of course, within loop constructs (for, while).
BACKGROUND:
http://apache-commons.680414.n4.nabble.com/jexl-JEXL-Secure-Sandbox-tt3626959.html