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copied!<p>I am with Limbic System on the NIO recommendation. I've added a NIO method to Daphna's test code and bench marked it against his two methods:</p> <pre><code>public static void timeNioReader () throws IOException { long bef = System.currentTimeMillis(); File file = new File("/Users/stu/test.txt"); FileChannel fc = (new FileInputStream(file)).getChannel(); MappedByteBuffer buf = fc.map(MapMode.READ_ONLY, 0, file.length()); boolean emptyLine = true; int counter = 0; while (buf.hasRemaining()) { byte element = buf.get(); if (element == '\r' || element == '\n') { if (!emptyLine) { counter += 1; emptyLine = true; } } else emptyLine = false; } long after = System.currentTimeMillis() - bef; System.out.println("timeNioReader Time: " + after + " Result: " + counter); } </code></pre> <p>Here are the warmed up results for a 89MB file:</p> <pre><code>timeBufferedReader Time: 947 Result: 747656 timeFileReader Time: 670 Result: 747656 timeNioReader Time: 251 Result: 747656 </code></pre> <p>NIO is 2.5x faster than FileReader and 4x fastser than the BufferedReader!</p> <p>With a 6.4MB file the results are even better, although the warm up time is much longer.</p> <pre><code>//jvm start, warming up timeBufferedReader Time: 121 Result: 53404 timeFileReader Time: 65 Result: 53404 timeNioReader Time: 40 Result: 53404 //still warming up timeBufferedReader Time: 107 Result: 53404 timeFileReader Time: 60 Result: 53404 timeNioReader Time: 20 Result: 53404 //ripping along timeBufferedReader Time: 79 Result: 53404 timeFileReader Time: 56 Result: 53404 timeNioReader Time: 16 Result: 53404 </code></pre> <p>Make of it what you will. </p>

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