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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"><head>
<!-- saved from url=(0087)file:///D:/User/Documents/progetti2015/filters_dox/doc-code/html/regexfilter_8java.html -->
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Doxygen filters: src/ms/utils/aarray/baseapp/filter/regexfilter.java File Reference</title>
<link href="./reg-exp_files/tabs.css" rel="stylesheet" type="text/css" />
<link href="./reg-exp_files/doxygen.css" rel="stylesheet" type="text/css" /></head><body>
<div class="contents"><dl class="user"><dt><br />
</dt></dl>
<h1><b>Summary of regular-expression constructs</b></h1>
(from JDK 6 documentation) <table summary="Regular
expression constructs, and what they match" border="0" cellpadding="1" cellspacing="0">
<tbody><tr align="left">
<th id="construct" align="left" bgcolor="#ccccff">Construct</th>
<th id="matches" align="left" bgcolor="#ccccff">Matches</th>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="characters">Characters</th>
</tr>
<tr>
<td headers="construct characters" valign="top"><i>x</i></td>
<td headers="matches">The character <i>x</i></td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\\</tt></td>
<td headers="matches">The backslash character</td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\0</tt><i>n</i></td>
<td headers="matches">The character with octal value <tt>0</tt><i>n</i>
(0 <tt><=</tt> <i>n</i> <tt><=</tt> 7)</td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\0</tt><i>nn</i></td>
<td headers="matches">The character with octal value <tt>0</tt><i>nn</i>
(0 <tt><=</tt> <i>n</i> <tt><=</tt> 7)</td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\0</tt><i>mnn</i></td>
<td headers="matches">The character with octal value <tt>0</tt><i>mnn</i>
(0 <tt><=</tt> <i>m</i> <tt><=</tt> 3,
0 <tt><=</tt> <i>n</i> <tt><=</tt> 7)</td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\x</tt><i>hh</i></td>
<td headers="matches">The character with hexadecimal value <tt>0x</tt><i>hh</i></td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\u</tt><i>hhhh</i></td>
<td headers="matches">The character with hexadecimal value <tt>0x</tt><i>hhhh</i></td>
</tr>
<tr>
<td headers="matches" valign="top"><tt>\t</tt></td>
<td headers="matches">The tab character (<tt>'\u0009'</tt>)</td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\n</tt></td>
<td headers="matches">The newline (line feed) character (<tt>'\u000A'</tt>)</td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\r</tt></td>
<td headers="matches">The carriage-return character (<tt>'\u000D'</tt>)</td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\f</tt></td>
<td headers="matches">The form-feed character (<tt>'\u000C'</tt>)</td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\a</tt></td>
<td headers="matches">The alert (bell) character (<tt>'\u0007'</tt>)</td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\e</tt></td>
<td headers="matches">The escape character (<tt>'\u001B'</tt>)</td>
</tr>
<tr>
<td headers="construct characters" valign="top"><tt>\c</tt><i>x</i></td>
<td headers="matches">The control character corresponding to <i>x</i></td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="classes">Character classes</th>
</tr>
<tr>
<td headers="construct classes" valign="top"><tt>[abc]</tt></td>
<td headers="matches"><tt>a</tt>, <tt>b</tt>, or <tt>c</tt> (simple
class)</td>
</tr>
<tr>
<td headers="construct classes" valign="top"><tt>[^abc]</tt></td>
<td headers="matches">Any character except <tt>a</tt>, <tt>b</tt>, or
<tt>c</tt> (negation)</td>
</tr>
<tr>
<td headers="construct classes" valign="top"><tt>[a-zA-Z]</tt></td>
<td headers="matches"><tt>a</tt> through <tt>z</tt> or <tt>A</tt>
through <tt>Z</tt>, inclusive (range)</td>
</tr>
<tr>
<td headers="construct classes" valign="top"><tt>[a-d[m-p]]</tt></td>
<td headers="matches"><tt>a</tt> through <tt>d</tt>, or <tt>m</tt>
through <tt>p</tt>: <tt>[a-dm-p]</tt> (union)</td>
</tr>
<tr>
<td headers="construct classes" valign="top"><tt>[a-z&&[def]]</tt></td>
<td headers="matches"><tt>d</tt>, <tt>e</tt>, or <tt>f</tt>
(intersection)</td></tr>
<tr>
<td headers="construct classes" valign="top"><tt>[a-z&&[^bc]]</tt></td>
<td headers="matches"><tt>a</tt> through <tt>z</tt>, except for
<tt>b</tt> and <tt>c</tt>: <tt>[ad-z]</tt> (subtraction)</td>
</tr>
<tr>
<td headers="construct classes" valign="top"><tt>[a-z&&[^m-p]]</tt></td>
<td headers="matches"><tt>a</tt> through <tt>z</tt>, and not <tt>m</tt>
through <tt>p</tt>: <tt>[a-lq-z]</tt>(subtraction)</td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="predef">Predefined character classes</th>
</tr>
<tr>
<td headers="construct predef" valign="top"><tt>.</tt></td>
<td headers="matches">Any character (may or may not match line terminators)</td>
</tr>
<tr>
<td headers="construct predef" valign="top"><tt>\d</tt></td>
<td headers="matches">A digit: <tt>[0-9]</tt></td>
</tr>
<tr>
<td headers="construct predef" valign="top"><tt>\D</tt></td>
<td headers="matches">A non-digit: <tt>[^0-9]</tt></td>
</tr>
<tr>
<td headers="construct predef" valign="top"><tt>\s</tt></td>
<td headers="matches">A withespace character: <tt>[ \t\n\x0B\f\r]</tt></td>
</tr>
<tr>
<td headers="construct predef" valign="top"><tt>\S</tt></td>
<td headers="matches">A non-withespace character: <tt>[^\s]</tt></td>
</tr>
<tr>
<td headers="construct predef" valign="top"><tt>\w</tt></td>
<td headers="matches">A word character: <tt>[a-zA-Z_0-9]</tt></td>
</tr>
<tr>
<td headers="construct predef" valign="top"><tt>\W</tt></td>
<td headers="matches">A non-word character: <tt>[^\w]</tt></td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="posix">POSIX character classes (US-ASCII only)<b /></th>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{Lower}</tt></td>
<td headers="matches">A lower-case alphabetic character: <tt>[a-z]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{Upper}</tt></td>
<td headers="matches">An upper-case alphabetic character:<tt>[A-Z]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{ASCII}</tt></td>
<td headers="matches">All ASCII:<tt>[\x00-\x7F]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{Alpha}</tt></td>
<td headers="matches">An alphabetic character:<tt>[\p{Lower}\p{Upper}]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{Digit}</tt></td>
<td headers="matches">A decimal digit: <tt>[0-9]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{Alnum}</tt></td>
<td headers="matches">An alphanumeric character:<tt>[\p{Alpha}\p{Digit}]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{Punct}</tt></td>
<td headers="matches">Punctuation: One of
<tt>!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~</tt></td>
</tr>
<!-- <tt>[\!"#\$%&'\(\)\*\+,\-\./:;\<=\>\?@\[\\\]\^_`\{\|\}~]</tt>
<tt>[\X21-\X2F\X31-\X40\X5B-\X60\X7B-\X7E]</tt>
-->
<tr>
<td headers="construct posix" valign="top"><tt>\p{Graph}</tt></td>
<td headers="matches">A visible character: <tt>[\p{Alnum}\p{Punct}]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{Print}</tt></td>
<td headers="matches">A printable character: <tt>[\p{Graph}\x20]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{Blank}</tt></td>
<td headers="matches">A space or a tab: <tt>[ \t]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{Cntrl}</tt></td>
<td headers="matches">A control character: <tt>[\x00-\x1F\x7F]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{XDigit}</tt></td>
<td headers="matches">A hexadecimal digit: <tt>[0-9a-fA-F]</tt></td>
</tr>
<tr>
<td headers="construct posix" valign="top"><tt>\p{Space}</tt></td>
<td headers="matches">A withespace character: <tt>[ \t\n\x0B\f\r]</tt></td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2">java.lang.Character classes (simple java
character type)</th>
</tr>
<tr>
<td valign="top"><tt>\p{javaLowerCase}</tt></td>
<td>Equivalent to java.lang.Character.isLowerCase()</td>
</tr>
<tr>
<td valign="top"><tt>\p{javaUpperCase}</tt></td>
<td>Equivalent to java.lang.Character.isUpperCase()</td>
</tr>
<tr>
<td valign="top"><tt>\p{javawithespace}</tt></td>
<td>Equivalent to java.lang.Character.iswithespace()</td>
</tr>
<tr>
<td valign="top"><tt>\p{javaMirrored}</tt></td>
<td>Equivalent to java.lang.Character.isMirrored()</td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="unicode">Classes for Unicode blocks and categories</th>
</tr>
<tr>
<td headers="construct unicode" valign="top"><tt>\p{InGreek}</tt></td>
<td headers="matches">A character in the Greek block (simple bloc)</td>
</tr>
<tr>
<td headers="construct unicode" valign="top"><tt>\p{Lu}</tt></td>
<td headers="matches">An uppercase letter (simple category)</td>
</tr>
<tr>
<td headers="construct unicode" valign="top"><tt>\p{Sc}</tt></td>
<td headers="matches">A currency symbol</td>
</tr>
<tr>
<td headers="construct unicode" valign="top"><tt>\P{InGreek}</tt></td>
<td headers="matches">Any character except one in the Greek block (negation)</td>
</tr>
<tr>
<td headers="construct unicode" valign="top"><tt>[\p{L}&&[^\p{Lu}]] </tt></td>
<td headers="matches">Any letter except an uppercase letter (subtraction)</td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="bounds">Boundary matchers</th>
</tr>
<tr>
<td headers="construct bounds" valign="top"><tt>^</tt></td>
<td headers="matches">The beginning of a line</td>
</tr>
<tr>
<td headers="construct bounds" valign="top"><tt>$</tt></td>
<td headers="matches">The end of a line</td>
</tr>
<tr>
<td headers="construct bounds" valign="top"><tt>\b</tt></td>
<td headers="matches">A word boundary</td>
</tr>
<tr>
<td headers="construct bounds" valign="top"><tt>\B</tt></td>
<td headers="matches">A non-word boundary</td>
</tr>
<tr>
<td headers="construct bounds" valign="top"><tt>\A</tt></td>
<td headers="matches">The beginning of the input</td>
</tr>
<tr>
<td headers="construct bounds" valign="top"><tt>\G</tt></td>
<td headers="matches">The end of the previous match</td>
</tr>
<tr>
<td headers="construct bounds" valign="top"><tt>\Z</tt></td>
<td headers="matches">The end of the input but for the final terminator, if any</td>
</tr>
<tr>
<td headers="construct bounds" valign="top"><tt>\z</tt></td>
<td headers="matches">The end of the input</td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="greedy">Greedy quantifiers</th>
</tr>
<tr>
<td headers="construct greedy" valign="top"><i>X</i><tt>?</tt></td>
<td headers="matches"><i>X</i>, once or not at all</td>
</tr>
<tr>
<td headers="construct greedy" valign="top"><i>X</i><tt>*</tt></td>
<td headers="matches"><i>X</i>, zero or more times</td>
</tr>
<tr>
<td headers="construct greedy" valign="top"><i>X</i><tt>+</tt></td>
<td headers="matches"><i>X</i>, one or more times</td>
</tr>
<tr>
<td headers="construct greedy" valign="top"><i>X</i><tt>{</tt><i>n</i><tt>}</tt></td>
<td headers="matches"><i>X</i>, exactly <i>n</i> times</td>
</tr>
<tr>
<td headers="construct greedy" valign="top"><i>X</i><tt>{</tt><i>n</i><tt>,}</tt></td>
<td headers="matches"><i>X</i>, at least <i>n</i> times</td>
</tr>
<tr>
<td headers="construct greedy" valign="top"><i>X</i><tt>{</tt><i>n</i><tt>,</tt><i>m</i><tt>}</tt></td>
<td headers="matches"><i>X</i>, at least <i>n</i> but not more than <i>m</i>
times</td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="reluc">Reluctant quantifiers</th>
</tr>
<tr>
<td headers="construct reluc" valign="top"><i>X</i><tt>??</tt></td>
<td headers="matches"><i>X</i>, once or not at all</td>
</tr>
<tr>
<td headers="construct reluc" valign="top"><i>X</i><tt>*?</tt></td>
<td headers="matches"><i>X</i>, zero or more times</td>
</tr>
<tr>
<td headers="construct reluc" valign="top"><i>X</i><tt>+?</tt></td>
<td headers="matches"><i>X</i>, one or more times</td>
</tr>
<tr>
<td headers="construct reluc" valign="top"><i>X</i><tt>{</tt><i>n</i><tt>}?</tt></td>
<td headers="matches"><i>X</i>, exactly <i>n</i> times</td>
</tr>
<tr>
<td headers="construct reluc" valign="top"><i>X</i><tt>{</tt><i>n</i><tt>,}?</tt></td>
<td headers="matches"><i>X</i>, at least <i>n</i> times</td>
</tr>
<tr>
<td headers="construct reluc" valign="top"><i>X</i><tt>{</tt><i>n</i><tt>,</tt><i>m</i><tt>}?</tt></td>
<td headers="matches"><i>X</i>, at least <i>n</i> but not more than <i>m</i>
times</td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="poss">Possessive quantifiers</th>
</tr>
<tr>
<td headers="construct poss" valign="top"><i>X</i><tt>?+</tt></td>
<td headers="matches"><i>X</i>, once or not at all</td>
</tr>
<tr>
<td headers="construct poss" valign="top"><i>X</i><tt>*+</tt></td>
<td headers="matches"><i>X</i>, zero or more times</td>
</tr>
<tr>
<td headers="construct poss" valign="top"><i>X</i><tt>++</tt></td>
<td headers="matches"><i>X</i>, one or more times</td>
</tr>
<tr>
<td headers="construct poss" valign="top"><i>X</i><tt>{</tt><i>n</i><tt>}+</tt></td>
<td headers="matches"><i>X</i>, exactly <i>n</i> times</td>
</tr>
<tr>
<td headers="construct poss" valign="top"><i>X</i><tt>{</tt><i>n</i><tt>,}+</tt></td>
<td headers="matches"><i>X</i>, at least <i>n</i> times</td>
</tr>
<tr>
<td headers="construct poss" valign="top"><i>X</i><tt>{</tt><i>n</i><tt>,</tt><i>m</i><tt>}+</tt></td>
<td headers="matches"><i>X</i>, at least <i>n</i> but not more than <i>m</i>
times</td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="logical">Logical operators</th>
</tr>
<tr>
<td headers="construct logical" valign="top"><i>XY</i></td>
<td headers="matches"><i>X</i> followed by <i>Y</i></td>
</tr>
<tr>
<td headers="construct logical" valign="top"><i>X</i><tt>|</tt><i>Y</i></td>
<td headers="matches">Either <i>X</i> or <i>Y</i></td>
</tr>
<tr>
<td headers="construct logical" valign="top"><tt>(</tt><i>X</i><tt>)</tt></td>
<td headers="matches">X, as a capturing group</td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="backref">Back references</th>
</tr>
<tr>
<td headers="construct backref" valign="bottom"><tt>\</tt><i>n</i></td>
<td headers="matches" valign="bottom">Whatever the <i>n</i><sup>th</sup>
capturing group matched</td>
</tr>
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="quot">Quotation</th>
</tr>
<tr>
<td headers="construct quot" valign="top"><tt>\</tt></td>
<td headers="matches">Nothing, but quotes the following character</td>
</tr>
<tr>
<td headers="construct quot" valign="top"><tt>\Q</tt></td>
<td headers="matches">Nothing, but quotes all characters until <tt>\E</tt></td>
</tr>
<tr>
<td headers="construct quot" valign="top"><tt>\E</tt></td>
<td headers="matches">Nothing, but ends quoting started by <tt>\Q</tt></td>
</tr>
<!-- Metachars: !$()*+.<>?[\]^{|} -->
<tr>
<th> </th>
</tr>
<tr align="left">
<th colspan="2" id="special">Special constructs (non-capturing)</th>
</tr>
<tr>
<td headers="construct special" valign="top"><tt>(?:</tt><i>X</i><tt>)</tt></td>
<td headers="matches"><i>X</i>, as a non-capturing group</td>
</tr>
<tr>
<td headers="construct special" valign="top"><tt>(?idmsux-idmsux) </tt></td>
<td headers="matches">Nothing, but turns match flags i d m s u x on - off</td>
</tr>
<tr>
<td headers="construct special" valign="top"><tt>(?idmsux-idmsux:</tt><i>X</i><tt>)</tt> </td>
<td headers="matches"><i>X</i>, as a non-capturing group
with the given flags i d m s u x on - off</td>
</tr>
<tr>
<td headers="construct special" valign="top"><tt>(?=</tt><i>X</i><tt>)</tt></td>
<td headers="matches"><i>X</i>, via zero-width positive lookahead</td>
</tr>
<tr>
<td headers="construct special" valign="top"><tt>(?!</tt><i>X</i><tt>)</tt></td>
<td headers="matches"><i>X</i>, via zero-width negative lookahead</td>
</tr>
<tr>
<td headers="construct special" valign="top"><tt>(?<=</tt><i>X</i><tt>)</tt></td>
<td headers="matches"><i>X</i>, via zero-width positive lookbehind</td>
</tr>
<tr>
<td headers="construct special" valign="top"><tt>(?<!</tt><i>X</i><tt>)</tt></td>
<td headers="matches"><i>X</i>, via zero-width negative lookbehind</td>
</tr>
<tr>
<td headers="construct special" valign="top"><tt>(?></tt><i>X</i><tt>)</tt></td>
<td headers="matches"><i>X</i>, as an independent, non-capturing group</td>
</tr>
</tbody></table>
<br /><i>Copyright 2008 Sun Microsystems, Inc. Reprinted with permission
(see http://java.sun.com/javase/6/docs/api/java/util/regex/Pattern.html#sum)</i>
<dl class="user"><dt><b>line terminators </b></dt><dd><br />
</dd></dl>
<p>The following are recognized as line terminators in regex:<br />
</p>
<ul>
<li>A newline (line feed) character ("\n"), - UNIX</li>
<li>A carriage-return character followed immediately by a newline character ("\r\n"), - DOS/WIN</li>
<li>A standalone carriage-return character ("\r"), - MAC</li>
<li>A next-line character ("\u0085Q"),</li>
<li>A line-separator character ("\u2028")</li>
<li>A paragraph-separator character ("\u2029").</li>
</ul>
<dl class="user"><dt><b>flag expressions (?idmsux-idmsux)</b></dt><dd><br />
</dd></dl>
<ul>
<li>In <em>block mode</em> [-b] the expressions "^" and "$" match at
the beginning and the end of the entire input sequence. The embedded
flag expression "(?m)" enables multiline mode, so these expressions
match just after or just before, respectively, any line terminator. </li>
<li>In <em>dotall mode</em>, the expression "." matches any character,
including a line terminator. By default this expression does not match
line terminators. Dotall mode can be enabled via the embedded flag
expression (?s). </li>
<li><em>Case-insensitive</em> matching for ASCII can be enabled via the embedded (?i). </li>
<li><em>Unicode-aware</em> case folding can be enabled via the embedded flag expression (?u). Requires (?i). </li>
<li><em>Comments mode</em> can be enabled via the embedded flag
expression (?x). In this mode, whitespace is ignored, and embedded
comments starting with # are ignored until the end of a line. </li>
<li><em>Unix-lines</em> mode can be enabled via the embedded flag
expression (?d). In this mode only "\n" line terminator is recognized
in the behavior of ".","^", and "$". </li>
</ul>
</div>
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