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POCasting a SeekableByteChannel to a FileChannel
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copied!<p>Directly from <a href="http://docs.oracle.com/javase/tutorial/essential/io/rafs.html" rel="nofollow">this</a> oracle java tutorial: </p> <blockquote> <p>The following code snippet opens a file for both reading and writing by using one of the newByteChannel methods. The SeekableByteChannel that is returned is cast to a FileChannel.</p> </blockquote> <p>This is the snippet they are talking about present in the same link I above mentioned.</p> <pre><code>String s = "I was here!\n"; byte data[] = s.getBytes(); ByteBuffer out = ByteBuffer.wrap(data); ByteBuffer copy = ByteBuffer.allocate(12); try (FileChannel fc = (FileChannel.open(file, READ, WRITE))) { // Read the first 12 // bytes of the file. int nread; do { nread = fc.read(copy); } while (nread != -1 && copy.hasRemaining()); // Write "I was here!" at the beginning of the file. fc.position(0); while (out.hasRemaining()) fc.write(out); out.rewind(); // Move to the end of the file. Copy the first 12 bytes to // the end of the file. Then write "I was here!" again. long length = fc.size(); fc.position(length-1); copy.flip(); while (copy.hasRemaining()) fc.write(copy); while (out.hasRemaining()) fc.write(out); } catch (IOException x) { System.out.println("I/O Exception: " + x); } </code></pre> <p>So basically they are talking about a Files.newByteChannel() method which returns a SeekableByteChannel object which in turn gets cast to a FileChannel. Well, I do not see this process. Is it hidden/running on the background/ or anyother sourcery magic kind of thing? Thanks in advance.</p>

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