RFR: 6873: Too many unnecessary missing resource exceptions thrown

[Marcus Hirt]

Also a tiny bit of cleanup.

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Commit messages:
 - Better naming
 - Adding newline
 - 6873: Too many unnecessary missing resource exceptions thrown

Changes: https://git.openjdk.java.net/jmc/pull/98/files
 Webrev: https://webrevs.openjdk.java.net/jmc/98/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JMC-6873
  Stats: 34 lines in 2 files changed: 14 ins; 11 del; 9 mod
  Patch: https://git.openjdk.java.net/jmc/pull/98.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/98/head:pull/98

PR: https://git.openjdk.java.net/jmc/pull/98