Re: BufferedWriter cannot handle InterruptedIOException

From:

Daniel Pitts <newsgroup.nospam@virtualinfinity.net>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 04 Jan 2012 13:41:19 -0800

Message-ID:

<4I3Nq.48143$mJ.28918@newsfe10.iad>

On 1/4/12 9:59 AM, Jan Burse wrote:

Dear All,

Just reading the spec of InterruptedIOException:

"Signals that an I/O operation has been
interrupted. An <code>InterruptedIOException</code>
is thrown to indicate that an input or output
transfer has been terminated because the thread
performing it was interrupted. The field {@link
#bytesTransferred} indicates how many bytes were
successfully transferred before the interruption
occurred."

But I think this does not carry over to BufferedOutputStream. I
find the following code there:

/** Flush the internal buffer */
private void flushBuffer() throws IOException {
if (count > 0) {
out.write(buf, 0, count);
count = 0;
}
}

In case that out throws an InterruptedIOException exception,
the write operation is directly terminated, and the count
is not set to zero.

As an effect next time flushBuffer is called again, the
same bytes are written out again.

Some better BufferedOutputStream class known?

Bye

Interestingly enough, I don't see any implementation of OutputStream in
the standard JDK which actually set that bytesTransferred field, so it
is always 0.

Often when a thread is interrupted, it is an indication that the
operation it is doing should be aborted. It was probably a mistake to
include the "bytesTransferred" field in the API, or perhaps it was
intended for read operations.

Hope this helps,
Daniel.