Replacing finalizers in FileInputStream, FileOutputStream, and adding
cleanup to RandomAccessFile
and NIO File Channels with Cleaner based implementations required
changes to FileDescriptor.
The specification of FileInputStream and FileOutputStream is changed to
remove the finalizer
behavior that required their respective close methods to be called.
This change to the behavior is tracked with CSR 8187325 [3].
The FileDescriptor implementations (Unix and Windows) provide a cleanup
function that is now used by
FIS, FOS, RAF, and async and normal FileChannels. Each requests
FileDescriptor to register a cleanup function
when the fd or handle is assigned and delegates to
FileDescriptor.close. If the respective
FileDescriptor.close method is not called, the fd or handle will be
closed when the FileDescriptor
is determined to be phantom reachable.
The other uses of FileDescriptor are not intended to be changed, for
example in sockets and datagrams.
Some tests were modified to not rely on finalization; new tests are
provided.
Comments are appreciated on both the CSR [3] and the implementation [1].
[1] webrev: http://cr.openjdk.java.net/~rriggs/webrev-fis-cleanup-8080225/
[2] Issue: https://bugs.openjdk.java.net/browse/JDK-8080225
[3] CSR: 8187325 FileInputStream/FileOutputStream should use the
Cleaner instead of finalize
https://bugs.openjdk.java.net/browse/JDK-8187325
Thanks, Roger
