Always remove short-lived objects from long-lived container objects when the task is over. For example, objects attached to a java.nio.channels.SelectionKey object must be removed when they are no longer needed. Doing so reduces the likelihood of memory leaks. Similarly, use of array-based data structures such as ArrayLists can introduce a requirement to indicate the absence of an entry by explicitly setting its individual array element to null.
This guideline specifically addresses objects in containers. For an instance where nulling out objects does not aid garbage collection, see OBJ54-JG. Do not attempt to help the garbage collector by setting local reference variables to null.
Noncompliant Code Example (Removing Short-Lived Objects)
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