RFR: 8268056: Update java.net and java.nio to use switch expressions

[Patrick Concannon]

Hi,

Could someone please review my code for updating the code in the `java.net` and `java.nio` packages to make use of the switch expressions?

Kind regards,
Patrick

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Commit messages:
 - 8268056: Update java.net and java.nio to use switch expressions

Changes: https://git.openjdk.java.net/jdk/pull/4285/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=4285&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8268056
  Stats: 122 lines in 4 files changed: 15 ins; 35 del; 72 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4285.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4285/head:pull/4285

PR: https://git.openjdk.java.net/jdk/pull/4285