reactor-core/src/main/java/reactor/core/publisher/Operators.java
public static void onErrorDropped(Throwable e, Context context) {
		Consumer<? super Throwable> hook = context.getOrDefault(Hooks.KEY_ON_ERROR_DROPPED,null);
		if (hook == null) {
			hook = Hooks.onErrorDroppedHook;
		}
		if (hook == null) {
			log.error("Operator called default onErrorDropped", e);
			throw Exceptions.bubble(e);
		}
		hook.accept(e);
	}
public static void onErrorDropped(Throwable e, Context context) {
		Consumer<? super Throwable> hook = context.getOrDefault(Hooks.KEY_ON_ERROR_DROPPED,null);
		if (hook == null) {
			hook = Hooks.onErrorDroppedHook;
		}
		if (hook == null) {
			log.error("Operator called default onErrorDropped", e);
			throw Exceptions.bubble(e);
		}
		hook.accept(e);
	}
An unexpected exception is about to be dropped.
<p>
If no hook is registered for {@link Hooks#onErrorDropped(Consumer)}, the dropped
error is logged at ERROR level and thrown (via {@link Exceptions#bubble(Throwable)}.

@param e the dropped exception
@param context a context that might hold a local error consumer