try-with-resources on arbitrary multiple files?

[Paul Sandoz]

On Apr 22, 2014, at 3:18 AM, Wang Weijun <weijun.wang at oracle.com> wrote:

> If I copy a file to another I can
> 
>  try (src = open(ifile); dest = open(ofile)) {
>    while (!src.EOF) dest.write(src.read());
>  }
> 
> but what if there are multiple destinations? Is there something like
> 

Not that i am aware of.

A fun little trick you can do is the following:

        File ifile = null;
        List<OutputStream> dests = new ArrayList<>();
        try (InputStream src = open(ifile); AutoCloseable ac = () -> closeAll(dests)) {
           dests.add(...);
            ....
        }

    static void closeAll(Collection<? extends OutputStream> l) throws IOException {
        ...
    }

But still that does not avoid the main work of closing stuff.

Paul.

>  try (src = open(ifile); manager = new CloseableManager()) {
>    for (ofile: ofiles) {
>      manager.register(open(ofile));
>    }
>    while (!src.EOF) {
>      buffer = src.read();
>      for (dest: manager) dest.write(buffer);
>    }
>  }
> 
> Thanks
> Max
> 

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