null check in Cluster.close

Description

If cluster.connect() (or some call that causes init) throws an exception a user may call cluser.close() to free any possibly dangling resources associated with that cluster (example from the spark connector). When init fails, you can't be sure all members of Cluster have been initialized. The driver should null check fields in close before cleaning up/freeing them.

Environment

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Pull Requests

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Fixed

Assignee

Greg Bestland

Reporter

Andy Tolbert

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Major
Configure