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FileObject src = null;

<-- In processing(), do your things, including src = children[0] -->

public void release() {
    FileSystem fs = null;

    this.src.close(); // Seems to still work even if this line is omitted
    fs = this.src.getFileSystem(); // This works even after the src is closed.
    this.fsManager.closeFileSystem(fs);
}

I have incorporated Detlev's suggestion into the example above, because the original release method used "((DefaultFileSystemManager) this.fsManager).close();" which worked once, but if you reinitialize and run the process again you will get an error containing

org.apache.commons.vfs.FileSystemException: Unknown scheme "sftp" in URI "sftp://sftpremote.example.com/data/source/fires/smoke/"

Detlev's method doesn't have this problem.

Compiling

Compile the source code with

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