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copied!<pre><code>Pattern p = Pattern.compile("[/\\\\]([a-zA-Z0-9_]+\\.ncx)$"); Matcher m = p.matcher("\\sample.ncx"); if (m.find()) { System.out.printf("The filename is '%s'%n", m.group(1)); } </code></pre> <p>output:</p> <pre><code>The filename is 'sample.ncx' </code></pre> <hr> <p><code>$</code> <a href="http://www.regular-expressions.info/anchors.html" rel="noreferrer">anchors</a> the match to the end of the string (or to the end of a line in multiline mode). It belongs at the <em>end</em> of your regex, not the beginning.</p> <p><code>[/\\\\]</code> is a <a href="http://www.regular-expressions.info/charclass.html" rel="noreferrer">character class</a> that matches a forward-slash or a backslash. The backslash has to be double-escaped because it has special meaning both in a regex and in a string literal. The forward-slash does <em>not</em> require escaping. </p> <p><code>[a-zA-Z0-9_]+</code> matches <strong>one or more</strong> of the listed characters; without the <a href="http://www.regular-expressions.info/repeat.html" rel="noreferrer">plus sign</a>, you were only matching <em>one</em>.</p> <p>The second forward-slash in your regex makes no sense, but you do need a backslash there to escape the <a href="http://www.regular-expressions.info/dot.html" rel="noreferrer">dot</a>--and of course, the backslash has to be escaped for the Java string literal.</p> <p>Because I switched from the <a href="http://www.regular-expressions.info/alternation.html" rel="noreferrer">alternation</a> (<code>|</code>) to a character class for the leading slash, the parentheses in your regex were no longer needed. Instead, I used them to <a href="http://www.regular-expressions.info/brackets.html" rel="noreferrer">capture</a> the actual filename, just to demonstrate how that's done.</p>

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