Более того вы не правы насчёт атомарности.
Проблема в том, что JVM, как я понимаю, сначала создаёт ссылку на объект и помещает её в переменную, потом же выполняет код в конструкторе и блоках инициализации.
Publishing internal state variables can compromise encapsulation and make it more difficult to preserve invariants; publishing objects before they are fully constructed can compromise thread safety.
A final mechanism by which an object or its internal state can be published is to publish an inner class instance, as shown in ThisEscape in Listing 3.7. When ThisEscape publishes the EventListener , it implicitly publishes the enclosing ThisEscape instance as well, because inner class instances contain a hidden reference to the enclosing instance.
public class ThisEscape {
public ThisEscape(EventSource source) {
source.registerListener(
new EventListener() {
public void onEvent(Event e) {
doSomething(e);
}
});
}
}If you are tempted to register an event listener or start a thread from a constructor, you can avoid the improper construction by using a private constructor and a public factory method, as shown in SafeListener in Listing 3.8.
public class SafeListener {
private final EventListener listener;
private SafeListener() {
listener = new EventListener() {
public void onEvent(Event e) {
doSomething(e);
}
};
}
public static SafeListener newInstance(EventSource source) {
SafeListener safe = new SafeListener();
source.registerListener(safe.listener);
return safe;
}
}