RFR: 8303891: Zip64SizeTest could use a sparse file

Thu Mar 9 12:22:22 UTC 2023

This PR suggests  we use a sparse file when the Zip64SizeTest writes a ZIP file with a 5GB entry.

The size requirement of this test is known to cause problems in some builds, see [JDK-8259866](https://bugs.openjdk.org/browse/JDK-8259866)

Using a sparse file reduces the disk space requirements of running the test from 5GB to 12K and also reduces the runtime from ~35 seconds to ~3 seconds on my Macbook Pro.

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Commit messages:
 - Add a missing "when" in Javadocs for SparseOutputStream
 - Remove introduced blank line
 - Remove double whitespace
 - Rewrite Zip64SizeTest to write to a sparse file

Changes: https://git.openjdk.org/jdk/pull/12948/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12948&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8303891
  Stats: 91 lines in 1 file changed: 56 ins; 17 del; 18 mod
  Patch: https://git.openjdk.org/jdk/pull/12948.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12948/head:pull/12948

PR: https://git.openjdk.org/jdk/pull/12948