RFR 8187631 : Refactor FileDescriptor close implementation

[Roger Riggs]

Hi Alan,

The updated webrev is:
http://cr.openjdk.java.net/~rriggs/webrev-fd-refactor-8187631-02/

I avoided cluttering the initial webrev with misc cleanup.

I renamed the parameters, corrected some old <code></code> markup and 
reordered
the declarations so a side-by side diff of the Unix and Windows 
FileDescriptor.java files
makes it easy to see the necessary differences.
(Perhaps a future cleanup can merge the two and manage all the other 
differences in the native code.)

Thanks, Roger

p.s. still not ready for final test and pushing til the repo re-opens

On 9/19/2017 8:48 AM, Alan Bateman wrote:
>
>
> On 18/09/2017 20:28, Roger Riggs wrote:
>> In anticipation of the re-opening (not yet) of the JDK 10 repo please 
>> review refactoring
>> the handling of closing of files in FileInputStream, 
>> FileOutputStream, RandomAccessFile,
>> and FileChannelImpl and related native code.
>>
>> The refactoring enables a future improvement to use the cleaner to 
>> close raw fds
>> when the FileDescriptors becomes unreferenced.
>>
>> Webrev:
>>    cr.openjdk.java.net/~rriggs/webrev-fd-refactor-8187631/
>>
>> Issue:
>>   https://bugs.openjdk.java.net/browse/JDK-8187631
> This looks okay to me.
>
> One thing to clear up in JavaIOFileDescriptorAccess is the parameter 
> names as it seems to use "obj" in some places, "fd" in others.
>
> -Alan