RFR: 8275840: Testing FileChannel.transferTo(FileChannel) with more than 2 GB of data [v2]

[Markus KARG]

> Testing `FileChannel.transferTo(FileChannel)` with more than 2 GB of data is covering the case that *multiple* iterations of `FileChannel.transferTo(FileChannel)` are actually performed by the test.
> 
> This change was requested Alan Bateman @AlanBateman.

Markus KARG has updated the pull request incrementally with two additional commits since the last revision:

 - Also it would be better to use constants.
 - It would probably be better to use a try-with-resources statement here to cleanly close the streams.

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/6093/files
  - new: https://git.openjdk.java.net/jdk/pull/6093/files/774078b6..04154625

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=6093&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=6093&range=00-01

  Stats: 10 lines in 1 file changed: 4 ins; 0 del; 6 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6093.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6093/head:pull/6093

PR: https://git.openjdk.java.net/jdk/pull/6093