More classloaders cleanup

[Sanne]

A very minor cleanup, but paving the road for other PRs which would otherwise depend on this.

• Stop using JarClassPathElement.readStreamContents(InputStream) which has been deprecated for years
• actually resolves a performance issue as this method is far less efficient in loading resources than the newly available alternatives
• prepare IoUtil to be reused more by upcoming improvements in the Hibernate extension

I haven't deleted readStreamContents yet as there are some tests using it still.

[gsmet]

I think this looks fine but I would like to let @dmlloyd have a look as he like low level stuff :).

[dmlloyd]

Looks good, but it is worth noting that for whatever reason, ZipFileInflaterInputStream does not optimize the array size used by readAllBytes, so there is going to be a buffered copy by that method in addition to the one potentially used internally by InflaterInputStream. Ideally we'd do the equivalent of readNBytes(entry.getUncompressedSize()) in this case. But, there are a lot of layers that make this difficult.

[quarkus-bot]

Status for workflow Quarkus CI

This is the status report for running Quarkus CI on commit 5773913.

✅ The latest workflow run for the pull request has completed successfully.

It should be safe to merge provided you have a look at the other checks in the summary.

You can consult the Develocity build scans.

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Flaky tests - Develocity

⚙️ JVM Tests - JDK 21

📦 extensions/smallrye-reactive-messaging/deployment

✖ io.quarkus.smallrye.reactivemessaging.hotreload.ConnectorChangeTest.testUpdatingConnector - History

• Expecting actual: ["-6","-8","-9","-10","-11","-12","-13","-14"] to start with: ["-6", "-7", "-8", "-9"] - java.lang.AssertionError

java.lang.AssertionError: 

Expecting actual:
  ["-6","-8","-9","-10","-11","-12","-13","-14"]
to start with:
  ["-6", "-7", "-8", "-9"]

	at io.quarkus.smallrye.reactivemessaging.hotreload.ConnectorChangeTest.testUpdatingConnector(ConnectorChangeTest.java:41)

[Sanne]

@dmlloyd thanks for the pointer to ZipFileInflaterInputStream .. I'll have a look at how that might affect us, but not considering this a blocker for the current patch as the code I'm avoiding to use is always allocating buffers inefficiently.
So at least we'll have a better implementation sometimes :)

I noticed this profiling bootstraps cycles during live-reload; I had not noticed the inefficiency in ZipFileInflaterInputStream so this is useful to know, it's entirely possible the scenarious I was looking at didn't trigger it. Either way, this shouldn't be making it worse.