RFR: 8312491: Update Classfile API snippets and examples [v9]

[Adam Sotona]

> This pull request updates Classfile API snippets and examples and adds missing javadoc.
> 
> Please review.
> 
> Thanks,
> Adam

Adam Sotona has updated the pull request incrementally with one additional commit since the last revision:

  fixing javadoc

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/14968/files
  - new: https://git.openjdk.org/jdk/pull/14968/files/c2c65575..0a333e18

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=14968&range=08
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=14968&range=07-08

  Stats: 118 lines in 10 files changed: 0 ins; 0 del; 118 mod
  Patch: https://git.openjdk.org/jdk/pull/14968.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14968/head:pull/14968

PR: https://git.openjdk.org/jdk/pull/14968