Replace `<pre>{@code ...}</pre>` patterns and the like with `{@snippet
lang=java : ...>`.
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Commit messages:
- 8308016: Use snippets in java.io package
Changes: https://git.openjdk.org/jdk/pull/13957/files
Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13957&range=00
Issue: https://bugs.openjdk.org/browse/JDK-8308016
Stats: 178 lines in 21 files changed: 27 ins; 7 del; 144 mod
Patch: https://git.openjdk.org/jdk/pull/13957.diff
Fetch: git fetch https://git.openjdk.org/jdk.git pull/13957/head:pull/13957
PR: https://git.openjdk.org/jdk/pull/13957
