Yeah, right good point that won't work for you.
How about using ProcessBuilder? I do this for calling shell scripts for
whenever I can't do something in an API (or it is already implemented in
bash scripts) and just need to execute something on the system.
some object like this
private val reader = actor {
debug("created actor: " + Thread.currentThread)
var continue = true
loopWhile(continue){
reactWithin(WAIT_TIME) {
case TIMEOUT =>
caller ! "react timeout"
case proc:Process =>
debug("entering first actor " + Thread.currentThread)
val streamReader = new
java.io.InputStreamReader(proc.getInputStream)
val bufferedReader = new
java.io.BufferedReader(streamReader)
val stringBuilder = new java.lang.StringBuilder()
var line:String = null
while({line = bufferedReader.readLine; line != null}){
stringBuilder.append(line)
stringBuilder.append("\n")
}
bufferedReader.close
caller ! stringBuilder.toString
}
}
}
def run(command: String, ran: (=> String)=>Unit) : Boolean = {
debug("gonna runa a command: " + Thread.currentThread + " = "+command)
val args = command.split(" ")
val processBuilder = new ProcessBuilder(args: _* )
processBuilder.redirectErrorStream(true)
val proc = processBuilder.start()
//Send the proc to the actor, to extract the console output.
reader ! proc
//Receive the console output from the actor.
receiveWithin(WAIT_TIME) {
case TIMEOUT => ran("receiving Timeout")
case result:String => ran(result)
}
true
}
note my debug statement is a logging trait so as to not have to if
(log.isDebugEnabled()) with by name param. I was going to bring this up
something I noticed while going through the code last night (e.g.
https://github.com/joestein/skeletor/blob/master/src/main/scala/util/Logging.scala)
figure now is a good time. Also don't have to ever do logger.getLogger
because that comes with the trait.
Maybe a generic utility and then you can just call and use it for sync() at
the OS level like you need?
On Sat, Nov 5, 2011 at 5:26 PM, Jay Kreps <[email protected]> wrote:
> But does that sync that file or all files, looking for the later...
>
> -jay
>
> Sent from my iPhone
>
> On Nov 5, 2011, at 1:44 PM, Joe Stein <[email protected]> wrote:
>
> > On the fileoutputstream you can get the filedescriptor using getFD() and
> then on that object you can sync()
> >
> > /*
> > Joe Stein
> > http://www.medialets.com
> > Twitter: @allthingshadoop
> > */
> >
> > On Nov 5, 2011, at 4:34 PM, Jay Kreps <[email protected]> wrote:
> >
> >> Does anyone know if there is an equivalent to the sync() system call
> >> available in Java? This is the system call that flushes all files. This
> >> seems like it might be a good optimization for the time-based log
> flush. If
> >> you are going to sequentially flush all the log partitions anyway it
> might
> >> be better to just do a single sync() and let the I/O scheduler have more
> >> leeway in the ordering of he writes. I know who to get the equivalent of
> >> fsync() or fdatasync() using FileChannel.force(...) to flush a single
> file
> >> but I don't know how to get the equivalent of sync().
> >>
> >> -Jay
>
--
/*
Joe Stein
http://www.linkedin.com/in/charmalloc
Twitter: @allthingshadoop <http://www.twitter.com/allthingshadoop>
*/
