33 lines
1.1 KiB
Java
33 lines
1.1 KiB
Java
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Creating a Shared File Lock on a File
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public static void main(String[] args)
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{
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try {
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// Obtain a file channel
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File file = new File("filename");
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FileChannel channel = new RandomAccessFile(file, "rw").getChannel();
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// Create a shared lock on the file.
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// This method blocks until it can retrieve the lock.
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FileLock lock = channel.lock(0, Long.MAX_VALUE, true);
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// Try acquiring a shared lock without blocking. This method returns
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// null or throws an exception if the file is already exclusively locked.
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try {
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lock = channel.tryLock(0, Long.MAX_VALUE, true);
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} catch (OverlappingFileLockException e) {
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// File is already locked in this thread or virtual machine
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}
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// Determine the type of the lock
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boolean isShared = lock.isShared();
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// Release the lock
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lock.release();
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// Close the file
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channel.close();
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} catch (Exception e) {
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}
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}
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