What the diff does not show

A review reads the lines that changed. The failures collected here live in everything the diff leaves out: the call sites that now mean something different, the dependencies that arrived without being declared, the exception that was swallowed on the way out. Reading only the patch is how correct-looking changes pass review and fail in production.

• A code review that only reads the diff cannot see what the change breaks
  19 September 2026 · The diff shows what the author did. The damage lives at the call sites, which are not in it.
• The exception that closed your resource hides the one that broke your code
  19 September 2026 · try-with-resources suppresses the close() failure and most logging throws it away. getSuppressed() is where the real cause went.
• Nine declared dependencies resolve to 406 on the classpath
  17 September 2026 · Nine direct, four hundred and six transitive. A note on what that costs.