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@robfletcher
Last active August 29, 2015 14:11
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Difference in static & dynamic code dispatching to field or getter
import groovy.transform.*
//@CompileStatic
class Person {
String name
private List<Person> friends
String friendNames() {
friends.collect { it.name }.join(", ")
}
}
assert new Person(name: "Rob").friendNames() == ""
@robfletcher
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Without @CompileStatic the code works as friends on line 9 dispatches to getFriends(). With @CompileStatic it dispatches direct to the private field and results in an NPE.

@robfletcher
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Interestingly if I change from friends.collect { it.name } to friends.name the dispatch changes!

@robfletcher
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Tried it in 2.3.8 and 2.4.0-beta-4 with the same result.

@robfletcher
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I've updated the gist now as apparently this is nothing to do with the presence of a getter. It's simply that dynamically compiled Groovy allows for calling certain GDK methods (all of them? only iterators?) on null.

@lhotari
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lhotari commented Dec 12, 2014

I think I've run in to this and reported a bug. I'll try to look it up.

@lhotari
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lhotari commented Dec 12, 2014

My problem was different indeed, it was http://jira.codehaus.org/browse/GROOVY-7098 . Fixed in 2.3.8 already .

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