implicit-methods

问题 I am struggling to understand implicit move operations when a class has a member whose move operations were not defined: int main() { struct A // no move: move = copy { A() = default; A(const A&) { cout << "A'copy-ctor\n"; }; A& operator=(const A&) { cout << "A'copy-assign\n"; return *this; } }; struct B { B() = default; A a; // does this make B non-moveable? unique_ptr<int> upi; // B(B&&) noexcept = default; // B& operator=(B&&)noexcept = default; }; A a; A a2 = std::move(a); // ok use copy

问题 As I understand from reading this post about the new invokedynamic bytecode instruction in JDK 7, it makes it possible to call methods on the objects which are not statically defined in the object's class and have those method calls be resolved to some concrete static methods in some other class by intercepting the method call target resolution (the post gives an example). Does this mean that Java 7 classes can have implicit methods like Scala has? If not how is implicit method resolution in