[GROOVY-9656] ExecutorService as a @Delegate calls the Runnable submit instead of the Callable one

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 3.0.5, 2.5.13
• Component/s: Compiler
• Assignee: Unassigned
• Reporter: Tim Yates
• Created: 24/Jul/20 15:09
• Updated: 24/Jul/20 15:09

Description

When ExecutorService is used with the @Delegate annotation, then casting a Closure to a Callable doesn't seem to call the correct method (we suspect it's calling the Runnable method)

 

Given the following script:

import java.util.concurrent.Callable
import java.util.concurrent.ExecutorService
import java.util.concurrent.Executors
import java.util.concurrent.Future
import java.util.concurrent.TimeUnit

class MyService {
    @Delegate ExecutorService delegateExecutorService = Executors.newCachedThreadPool()
}

def test(ExecutorService s) {
    println s.submit { 42 }.get()
    println s.submit([call: { 42 }] as Callable).get()
    println s.submit({ 42 } as Callable).get()
    s.shutdownNow()
}

println "Delegated ExecutorService"
test(new MyService())

println()

println "Actual ExecutorService"
test(Executors.newCachedThreadPool())

The output is:

Delegated ExecutorService
null
42
null

Actual ExecutorService
null
42
42

Whereas I was expecting the first delegated result to be the same as calling the actual executor service...

Apologies if this is a dupe, or documented, I did try and look, but to no avail

Cheers

Tim