Setting local reference variables to null to "help the garbage collector" is unnecessary. It adds clutter to the code and can make maintenance difficult. Java just-in-time compilers (JITs) can perform an equivalent liveness analysis; in fact, most implementations do so. A related bad practice is use of a finalizer to null out references. See MET12-J. Do not use finalizers for additional details.
This guideline applies specifically to local variables. For a case where explicitly erasing objects is useful, see OBJ55-JG. Remove short-lived objects from long-lived container objects.
Noncompliant Code Example
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