Contiguous disk pages

Hi all,
When I write a lot of data in a file in one method call (like RandomAccessFile.write(byte[])), I suppose that the JVM (and the OS) make its best to write data on contiguous disk pages. Is-it exact ?
If yes, could you tell me if it's the same for method that extend the file without writing data (like RandomAccessFile.setLength(long)) ?
Thanks in advance
Jean

The actual file i/o is controlled by the OS; Java just "hooks" into that. So, technically, yes, the OS will try to write large files in contiguous blocks. Modifying a file, on the other hand, will really depend upon how the OS itself handles that kind of request, plus disk fragmentation.

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