```
@Target(FIELD)
@Retention(RUNTIME)
public @interface NewField
```
This annotation is applied to member variables of weaved classes (classes marked with Weave) so that they are treated as new fields. If this annotation is not present, the agent will expect the referenced field to be present on the original class and will not load the weaved instrumentation if it is not. New Relic stores these values in a map keyed by the object having the new field. The map uses weak reference semantics. Under normal circumstances, the entry holding the key and value will be made available for garbage collection after all other references to the key, both inside and outside of the map, have been cleared by the garbage collector. As with all weakly-keyed maps, this automatic cleanup of unused entries cannot occur if a value holds an ordinary object reference, either direct or indirect, to its own key. Therefore, if the value of a new field holds a reference to the key, the programmer using this API is required to assign null to the value at some appropriate life cycle point in order to allow eventual removal of the map entry. If this is not done, the entry will never be removed and the map may grow without bound.

Annotation Type NewField