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copied!<p>Since your code has performance issues, you first need to find bottle neck. You can profile it with profiler available with IDE you use.</p> <p>However since your code is not high in computation but IO intensive, both in reading file and output using System.out.print, that is where I would suggest you to improve on for improving on file IO.</p> <p>.</p> <p>Replace this line of code</p> <pre><code>Scanner scanner = new Scanner(new File("i:\\1\\2.txt")); </code></pre> <p>.</p> <p>With this lines of code</p> <pre><code>File file = new File("i:\\1\\2.txt"); BufferedReader br = new BufferedReader( new FileReader(file) ); Scanner scanner = new Scanner(br); </code></pre> <p>Let us know if this helps.</p> <p>.</p> <p>Since previous solution did not helped much, I made few more changes to improve your code. You may have to correct errors in parsing if any. I was able to display output of parsing 392832 lines in approx 5 seconds. Original solution takes more than 50 seconds.</p> <p><strong>Chages are as below:</strong></p> <ol> <li>Use of StringTokenizer instead of Scanner</li> <li>Use of BufferedReader for reading file</li> <li>Use of StringBuilder to buffer output</li> </ol> <p>.</p> <pre><code>public class FileParse { private static final int FLUSH_LIMIT = 1024 * 1024; private static StringBuilder outputBuffer = new StringBuilder( FLUSH_LIMIT + 1024); private static final long countCellId; public static void main(String[] args) throws IOException { long start = System.currentTimeMillis(); String fileName = "i:\\1\\2.txt"; File file = new File(fileName); BufferedReader br = new BufferedReader(new FileReader(file)); String line; while ((line = br.readLine()) != null) { StringTokenizer st = new StringTokenizer(line, ";|, "); while (st.hasMoreTokens()) { String token = st.nextToken(); processToken(token); } } flushOutputBuffer(); System.out.println("----------------------------"); System.out.println("CELLID Count: " + countCellId); long end = System.currentTimeMillis(); System.out.println("Time: " + (end - start)); } private static void processToken(String token) { if (token.startsWith("CELLID=")) { String value = getTokenValue(token); outputBuffer.append("CELLID:").append(value).append("\n"); countCellId++; } else if (token.startsWith("ENSUP=")) { String value = getTokenValue(token); outputBuffer.append("ENSUP:").append(value).append("\n"); } else if (token.startsWith("ENCHO=")) { String value = getTokenValue(token); outputBuffer.append("ENCHO:").append(value).append("\n"); } if (outputBuffer.length() > FLUSH_LIMIT) { flushOutputBuffer(); } } private static String getTokenValue(String token) { int start = token.indexOf('=') + 1; int end = token.length(); String value = token.substring(start, end); return value; } private static void flushOutputBuffer() { System.out.print(outputBuffer); outputBuffer = new StringBuilder(FLUSH_LIMIT + 1024); } } </code></pre> <p>.</p> <p><strong>Update on ENSUP and MSLH:</strong></p> <p>To me it looks like you have switched ENSUP and MSLH in if statement as below. Hence you see "MSLH" value for "ENSUP" and vice a versa.</p> <pre><code>} else if (token.startsWith("MSLH=")) { String value = getTokenValue(token); outputBuffer.append("ENSUP:").append(value).append("\n"); } else if (token.startsWith("ENSUP=")) { String value = getTokenValue(token); outputBuffer.append("MSLH:").append(value).append("\n"); } </code></pre>

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