I use the Groovy Script as a sort of function that returns a specific type and
call it repeatedly with different bindings, the following is an excerpt of my
code:
private static final GroovyClassLoader GROOVY_CLASSLOADER = new
GroovyClassLoader();
private static final Map<String, Script> functionCache = new HashMap<>();
public static MyReturnType evaluate(String functionString, Object myDataToBind)
{
Script script = null;
try {
script = resolveFunction(functionString);
} catch (Exception e) {
throw new IllegalArgumentException("The function could not be
resolved: " + functionString, e);
}
script.getBinding().setVariable(VAR, myDataToBind);
Object o = null;
try {
o = script.run();
} catch (Exception e) {
throw new IllegalArgumentException("The function is not valid:
" + functionString, e);
}
MyReturnType ts = null;
if(o instanceof MyReturnType) {
ts = (MyReturnType) o;
} else {
throw new IllegalArgumentException("The function doesn't
evaluate to a MyReturnType: " + functionString);
}
return ts;
}
Script resolveFunction(String f) throws InstantiationException,
IllegalAccessException {
if(functionCache.containsKey(f)) { // functions are likely repeated many
times in one chunk
return functionCache.get(f);
}
// fiddle a bit with the string representation of the script
Class<?> clazz = GROOVY_CLASSLOADER.parseClass(f);
Object cc = clazz.newInstance();
Script script = (Script) cc;
functionCache.put(f, script);
return script;
}
From: Ralph Johnson [mailto:[email protected]]
Sent: Tuesday, February 13, 2018 3:41 AM
To: [email protected]
Subject: Re: Executing Groovy DSL scripts concurrently
That guide to integrating is *very* interesting! I had never seen
GroovyClassLoader before.
I work with a large application that uses GroovyShell a lot. It has thousands
of scripts. Sometimes they call each other recursively, which runs into the
same problem with shared Bindings that concurrency has. I wondered why a
script couldn't be a class so that I could instantiate it each time it ran, and
so not have to share bindings. I am pretty sure that with GroovyClassLoader,
I can do it. Thanks for pointing it out!
-Ralph Johnson
On Mon, Feb 12, 2018 at 2:10 AM, Korbee Reinout
<[email protected]<mailto:[email protected]>> wrote:
[Boxbe]<https://www.boxbe.com/overview>[http://www.boxbe.com/stfopen?tc_serial=36637963201&tc_rand=1084693400&utm_source=stf&utm_medium=email&utm_campaign=ANNO_CLEANUP_ADD&utm_content=001]This
message is eligible for Automatic Cleanup!
([email protected]<mailto:[email protected]>) Add cleanup
rule<https://www.boxbe.com/popup?url=https%3A%2F%2Fwww.boxbe.com%2Fcleanup%3Fkey%3DIACL3oJKfUFUI8o%252BV%252BSvhRz7CVhfgVAef%252BSiCMBkkH0%253D%26token%3DmOLRlI1UuZw8SVNtchg7i08qve4GprNHZPJ%252FuFCSHStD%252F7QwDC7CiD1J%252FXpeem8HBaBmBiSO7lwH0XUlOXqrrSd4Lxlv%252BVtlgDCgdh9yWPHzz1U9J3EMThUh%252B8pDNwMq4JUlD72gGHFJICg5jMje9A%253D%253D&tc_serial=36637963201&tc_rand=1084693400&utm_source=stf&utm_medium=email&utm_campaign=ANNO_CLEANUP_ADD&utm_content=001>
| More
info<http://blog.boxbe.com/general/boxbe-automatic-cleanup?tc_serial=36637963201&tc_rand=1084693400&utm_source=stf&utm_medium=email&utm_campaign=ANNO_CLEANUP_ADD&utm_content=001>
Hi,
According to:
http://docs.groovy-lang.org/latest/html/documentation/guide-integrating.html
“You must be very careful when using shared data in a multithreaded
environment. The Binding instance that you pass to GroovyShell is not thread
safe, and shared by all scripts.”
There are some guidelines regarding multi-threading and thread-safety. Before
attempting something like this, ask yourself the question, “can I guarantee
that my code is thread safe?”, which is very different from running a
successful test without concurrency issues.
You could use the GroovyClassLoader directly and keep the compiled scripts in a
cache, see the mentioned docs on how to obtain thread-safety with the Binding
object.
From: K Adithyan (tech) [mailto:[email protected]<mailto:[email protected]>]
Sent: Wednesday, February 7, 2018 4:15 PM
To: [email protected]<mailto:[email protected]>
Subject: Executing Groovy DSL scripts concurrently
Team,
Our application is a Root Cause Analysis Computation Engine for Telecom
networks. We have been implementing the logics in java only so far.
We are now planning to write DSLs for each feature and write the logics using
the DSL. We have implemented a framework for plugging in any number of DSLs and
integrated that DSL Framework with our application.
Each of the logics written over the DSL are executed concurrently using 40 or
50 or 60 threads based on the rate of the incoming events. Due to the
concurrency, we are now creating `GroovyShell` object for every execution and
calling `shell.evaluate(ourScriptFile)` to run the DSL scripts with our own
Binding object and delegates.
This prevents the system to run the logic at its own speed. Everytime parsing
and running takes significant time which reduces the event handling capacity of
the application.
I have attempted with `GroovyShell` and `GroovyScriptEngine`. But both are
offering same performance levels. GroovyShell is slightly better than
GroovyScriptEngine.
Under these circumstances, what is the best way to wrap our script logic, that
is based on our own DSLs, and run it concurrently without any overhead for
parsing, compilation, etc?????????
Pls advice
Reg,
Adithyan K
This e-mail message contains confidential information and is intended only for
the named recipient(s). If you are not an intended recipient, any disclosure,
copying or distribution is prohibited. Please notify the sender immediately by
e-mail if you have received this message in error and delete this message from
your system. As internet communications are not secure, the Swiss National Bank
accepts no liability for any errors or omissions in the contents of this
message. Any views expressed in this message are those of the individual
sender, except where the sender specifically states them to be the views of the
Swiss National Bank.
