public static <U> AtomicLongFieldUpdater<U> newUpdater (Class<U> tclass, String fieldName)

Creates and returns an updater for objects with the given field. The Class argument is needed to check that reflective types and generic types match.

tclass    the class of the objects holding the field
fieldName    the name of the field to be updated
<U>    the type of instances of tclass

Returns:  the updater

IllegalArgumentException    if the field is not a volatile long type
RuntimeException    with a nested reflection-based exception if the class does not hold field or is the wrong type, or the field is inaccessible to the caller according to Java language access control