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    <p>There are a number of problems with this approach. </p> <ol> <li><p>Unless you've called String.intern then your from string is probably not the same from as the other one you are calling. Relying on the behaviour of the internal java string cache is not very robust.</p></li> <li><p>you aren't properly disposing of your XMLDecoder in a finally block, any exception thrown during that call will leak the file description associated with that FileInputStream.</p></li> <li><p>You don't need to wrap e in another Exception(e), you can just throw e as you have declared the enclosing method also throws Exception</p></li> <li><p>Catching/Throwing exception is a code smell. Yes, it is a super class of IOException, and whatever XML decoding exception might be thrown, but its also a superclass of a bunch of other things you probably didn't want to catch, NullPointerException for instance.</p></li> </ol> <p>To answer your question, how can you serialize access to a shared file to ensure its not being used by more than one thread, is tricky. FileChannel.lock() doesn't work inside the JVM, they just lock the file from modification by other processes in the machine.</p> <p>My approach would be to strip any locking out of this class and wrap it in something that is aware of the threading issues of your code.</p> <p>I'd also not pass a String as the filename, but a File, which gives you the ability to use File.createTempFile(2) to create opaque filenames between the thing writing xml and the thing reading xml.</p> <p>Finally, do you want to synchronise access to a shared file, or fail when you detect multiple access to the same file? </p>
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    1. POsynchronizing io operation in java on a string method argument?
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    1. USDave Cheney
    1. USDave Cheney
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    1. COThanks. Fixed those dumb mistakes of mine. Could you please elaborate on "File.createTempFile(2) to create opaque filenames..."? Just don't get the idea considering that if smth has been written doesn't mean it would be read during the same session. Want to synchronize access.
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    2. COCan you update your original question? 300 Chars is too short to explain what you want.
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