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    <p>To answer your questions directly:</p> <p>1) You pretty much had your file reader, but you needn't bother with the <code>Map</code>, a <code>List</code> will suffice.</p> <pre><code>Scanner scanner = new Scanner(new FileReader("C:\\Path\\boards.txt")); List&lt;String&gt; lines = new ArrayList&lt;String&gt;(); while (scanner.hasNextLine()) { String columns = scanner.nextLine(); lines.add(columns); } </code></pre> <p>2) To grab a random line, just pick a random index into the <code>List</code>.</p> <pre><code>Random random = new Random(); int randomLineIndex = random.nextInt(lines.size()); String randomLine = lines.get(randomLineIndex); </code></pre> <p>Now, all that said, if you don't need to load the whole file, don't. If you just need to grab a random line from the file then go right for it and save yourself computation and memory.</p> <p>To do so, you'll first need to known the number of lines in the file. <a href="https://stackoverflow.com/questions/1277880/how-can-i-get-the-count-of-line-in-a-file-in-an-efficient-way">This question</a> gives you:</p> <pre><code>String file = "C:\\Path\\boards.txt"; BufferedReader reader = new BufferedReader(new FileReader(file)); int lineCount = 0; while (reader.readLine() != null) lineCount++; reader.close(); </code></pre> <p>Now you know how many lines there are and can pick one at random:</p> <pre><code>Random random = new Random(); int randomLineIndex = random.nextInt(lineCount); </code></pre> <p>Then you can grab that line and ignore the rest:</p> <pre><code>reader = new BufferedReader(new FileReader(file)); int i = 0; while (++i &lt; randomLineIndex) // Skip all lines before the one we want reader.readLine(); String randomLine = reader.readLine(); </code></pre>
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    1. POHow to save contents of large .txt file in a HashMap but only display one line (randomly)
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    1. USSean Connolly
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    1. COThank you, Sean. This works great!
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    2. CONo problem, cheers.
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