If a call to an interface method is included in a rule body Byteman may fail to type check it correctly, notifying an invalid method error (it probably should say unknown method but anyway ...). This only happens in a specific case where the class which implements the interface is abstract and so does not actually include an implementation method.

As an example, assume

interface I

{ public void foo(); }

abstract class Foo implements I { public void test()

{ ... } }

class Bar extends Foo { public void foo() { ... }

}

and then let the rule be

RULE bad method check
CLASS Foo
METHOD test
IF TRUE
DO $0.foo()
ENDRULE

Method foo is only looked for via classes Foo and Object. Since neither of them implements foo() the lookup fails. However, foo() should also be searched for via interface I (and then also executed via the Method instance defined by that interface).