Re: Locking objects in an array

From:

Philipp <djbulu@gmail.com>

Newsgroups:

comp.lang.java.programmer

Date:

Tue, 5 May 2009 09:34:56 -0700 (PDT)

Message-ID:

<796c4a73-7485-4b59-adbf-4f8091905877@j12g2000vbl.googlegroups.com>

On May 5, 6:22 pm, Eric Sosman <Eric.Sos...@sun.com> wrote:

Patricia Shanahan wrote:

[...]
Synchronization with varying block sizes would be more complicated.

One way to approach it would be with recursion. I'll illust=

rate

with a List and an Iterator, although they're by no means the only way
to keep track:

        List<Thing> things = new ...;
        for (int dr = 0; dr < rspan; ++dr) {
            for (int dc = 0; dc < cspan; ++dc)
                things.add(lattice[r+dr][c+dc]);
        }
        doDirtyDeed(things.iterator(), things);

        ...

        void doDirtyDeed(Iterator<Thing> it, List<Thing> things) =

{

            if (it.hasNext()) {
                synchronized(it.next()) {
                    doDirtyDeed(it, things);
                }
            }
            else {
                // all the Things' locks are now held
                // do things to Things in "things"
            }
        }

This is a clever approach. Thanks for sharing it.
Phil