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<!--
<h2>Table of Contents</h2>
<a href="using.html">Using the QuickREx Plugin</a>
<ul>
<li><b>Using the QuickREx View for testing and evaluating regular expressions</b></li>
<ul>
<li><a href="persistence.html">Saving, Loading and Organizing Regular Expressions and Test-Texts</a></li>
<li><a href="regExpressions.html">How QuickREx evaluates the Regular Expressions</a></li>
</ul>
</li>
<li><a href="reLibView.html">Using the Reg. Exp. Library View for keeping and organizing regular expressions</a></li>
<li><a href="settings.html">Changing Color- and Font-settings</a></li>
<li><a href="completions.html">Customizing TAB-completion and the Edit-dialog</a></li>
</ul>
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<h1>Using the QuickREx View for testing and evaluating regular
expressions</h1>
<ul type="square">
<li><a href="#QuickRExViewDetails">The QuickREx View</a></li>
<li><a href="#testing">Testing Regular Expressions</a></li>
<li><a href="#timeOutAndOfflineEvaluation">Time-out and offline evaluation</a></li>
<li><a href="#selectingImpl">Selecting the Reg-Exp implementation</a></li>
<li><a href="#settingFlags">Setting global compiler-flags</a></li>
<li><a href="#tabCompletion">Using TAB-completion</a></li>
<li><a href="#reEditDialog">Using the Reg-Exp-Edit dialog</a></li>
<li><a href="#copyToJava">Copying Regular Expressions to Java-code</a></li>
<li><a href="#grepping">Extracting all matches from text</a></li>
</ul>
<h2 name="QuickRExViewDetails">The QuickREx View</h2>
<p>If the Plugin is installed, you should find a view named <strong>QuickREx</strong> offered under
<strong>Window > Show View > Other...</strong> in the
category <strong>QuickREx</strong>.</p>
<p>The view looks as displayed in the screenshot below.</p>
<img alt="The QuickREx View" src="images/QuickRExView.png">
<p>The cool-bar icons are detailed in the following screenshot.</p>
<img alt="The QuickREx Coolbar" src="images/QuickRExCoolBar.png"/>
<a name="testing"><h3>Testing Regular Expressions</h3></a>
<p>As you type text into the test-text area or a regular expression
into the area for the regular expressions, the expression is
constantly evaluated. The information on matches and groups is
updated on the fly and matches are highlighted in the
test-text.</p>
<p>Below is a screenshot of a situation where there are no groups
but several matches. The match highlighted in green is the current
one. All information on groups pertains to the current match.</p>
<img alt="The QuickREx View with matches" src="images/QuickRExView2.png"/>
<p>The information next to the buttons used to navigate between the
matches is to be interpreted as "There are 7 matches altogether,
the current match (highlighted in green) has a start-index of 2 and
an end-index of 4". As you can see there are no groups in the
current match. You can navigate between the matches using the
'Previous' and 'Next' buttons near the label 'Matches'. If there
were groups in the current match, you could navigate through the
groups using the 'Previous' and 'Next' buttons near the label
'Groups'.</p>
<img alt="The QuickREx View with matches which have groups" src="images/QuickRExView3.png"/></img>
<p>The above screenshot displays a case where there are groups in
the current match. The current group is indicated by a bold font
and the contents of the group are printed in the information-are
next to the group-navigation buttons. The information there is to
be interpreted as "There are 2 groups in the current match, the
current group is the first one, containing 'the plugin evaluates
'".</p>
<a name="timeOutAndOfflineEvaluation"><h3>Time-out and offline evaluation</h3></a>
<p>As of Version 3, evaluation of the regular expression can be done
offline by unsetting the mark at <strong>'Live-evaluation'</strong> and using
the <strong>'Evaluate'</strong>-button if evaluation is in order.</p>
<p>Also from Version 3 on, evaluation of the regular expression takes
place in a separate thread and may be cancelled by the user or is automatically
cancelled if it takes too long. The dialog for cancelling the evaluation appears
with a small delay so that you will not notice it during fast live-evaluation.</p>
<p>The time-out behaviour is configurable from the preference page available
under <strong>'Window > Preferences...'</strong> in the category
<strong>'QuickREx'</strong>. The preference page is displayed with the default settings
in the screenshot below.</p>
<img alt="The QuickREx preference-page" src="images/QuickRExPreferencePage.png"/></img>
<a name="selectingImpl"><h3>Selecting the Reg-Exp implementation</h3></a>
<p>QuickREx offers the most widely used implementations of
Regular Expressions in the Java-world:</p>
<ul>
<li>JDK Regular Expressions (available since 1.4)</li>
<li>Jakarta ORO Perl-style Regular Expressions (ORO-Version
2.0.8, supports Perl 5.003 Regular Expressions)</li>
<li>Jakarta ORO Awk-style Regular Expressions (ORO-Version
2.0.8)</li>
<li>JRegex Regular Expressions (Version 1.2_01, supports
Perl 5.6 Regular Expressions)</li>
<li>Jakarta Regexp Regular Expressions (Version 1.4)</li>
</ul>
<p>The default implementation is the JDK-one. To change the
implementation, use the leftmost buttons in the view's coolbar (see
screenshot above). The expression will immediatly be re-evaluated.
Also, the TAB-completion will adjust to offer the completions
defined for the selected implementation.</p>
Alternatively, you may use the view's drop-down menu and select the
implementation of your choice (see figure). <img alt=
"The drop-down menu of QuickREx" src="images/dropDownMenu.png">
<a name="settingFlags"><h3>Setting global compiler-flags</h3></a>
<p>You can set global compiler flags with any of the
implementations QuickREx offers. This is done at the bottom of the
view (see screenshot at the top of the page). To keep the view
small, the "Global Flags"-section is folded away when the view is
opened. To access it, click on the section-header.</p>
<p>The state of the flags is saved when you close the view or leave
the Workbench. Note that there are different flags depending on the
chosen implementation. Also note that the flags do behave slightly
differently, depending on the implementation chosen. Check the
tool-tip texts for the check-boxes to find details about the
individual flags (see screenshot).</p>
<img alt="The QuickREx View with an example tool-tip for a flag"
src="images/QuickRExView4.png">
<a name="tabCompletion"><h3>Using TAB-completion</h3></a>
<p>As in several specialized editors within Eclipse, you can use
TAB-completion for regular expressions in QuickREx. To get a list
of proposals for completion of the current expression, hit
'Ctrl+Space' while editing in the area for regular expressions. An
assistant will open as displayed in the below screenshot. Scrolling
through the suggestions also updates the hint on the right side of
the proposal. When you select a proposal, QuickREx will try to work
out whether the already typed in characters should be part of an
expression or not.</p>
<img alt="The code-completion assistant" src=
"images/TABCompletion.png">
<p>Note that due to the complexity of regular expressions,
TAB-completion is not as accurate as it is e.g. in the Java-editor.
Sometimes the proposed possibilities may result in illegal
patterns. Generally, QuickREx tries to do a good job in guessing
what you may want. To this end, the rules are roughly as
follows:</p>
<ul>
<li>Offer all completions which are not definitely illegal. Thus
for example, you will not be offered '+' ("Greedy match 1 or more
times") at the beginning of the regular expression - but almost
anything else.</li>
<li>Try to guess the intentions of the user in cases where things
are pretty clear. Offer things starting with the most likely
ones. They are the exceptions, but there are cases where it is
clear what the user is after. Thus, the input '\p{Lo' is very
likely part of '\p{Lower}'. This will be the first offer.</li>
<li>In case there are several potential completions even within
the rules, offer the shortest ones first. Thus, if you start with
'\' and ask for completion, you will be offered '\\', '\0', ...
before \p{Lower}. If you keep typing and the next character typed
is a 'p', you will notice how the order of proposals
changes.</li>
</ul>
<a name="#reEditDialog"><h3>Using the Reg-Exp-Edit dialog</h3></a>
<p>If you prefer a dialog with selection-lists and some bracket-highlighting
over the combo to edit the regular expression, click the 'Edit...'-button
to the right of the combo for the regular expression. The dialog displayed in the
following figure will open:</p>
<img alt="The edit-dialog for regular expressions" src="images/reEditDialog.png"/></img>
<p>The dialog differs for the different flavours, since they offer different
options for multiplicities, wildcards, etc.</p>
<p>The text-field at the top of the dialog is used to type the regular expression. As
you change the expression, the plug-in-view updates and the expression is evaluated
against the current test-text (assuming you use live-evaluation). The text-field also
offers some bracket-highlighting.</p>
<p>For expressions like wildcards etc, you will find the most commonly used options
in the drop-down-lists. Whenever a list-entry is selected, the field at the bottom
of the dialog displays a short explanation. If you want to use an expression, press
'Insert' next to the drop-down. The expression will be inserted at the current edit-position
of the regular expression.</p>
<a name="copyToJava"><h3>Copying Regular Expressions to Java-code</h3></a>
<p>Typically, regular expressions are full with backslashes and the
like. To use them in code, you need to escape special characters.
When the number of backslashes increases, this gets annoying. To
simplify the task and to reduce the potential sources of errors,
QuickREx offers the possibility of properly escaping the current
regular expression and inserting them at the current curser
position of (or replacing the current selection in) the last active
editor window. To this end, simply place the cursor where you want
the regular expression to go in the editor and press '<strong>Copy
to Java</strong>' in the coolbar or select it in the drop-down (see
above).</p>
<a name="grepping"><h3>Grep - extracting all matches from text</h3></a>
<p>If you want to extract only the matches for a particular regular
expression from the current test-text, simply press the button
'<strong>Grep</strong>' in the coolbar or select it in the
drop-down (see above). A dialog as displayed below will open,
holding all matches separated by line-feeds. You can copy the
result from the dialog to the clipboard to use it anywhere else as
usually.</p>
<img alt="The dialog holding matches after grepping" src=
"images/GrepResult.png">
<p> </p>
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distrib
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Mandriva
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2010.0
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i586
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media
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contrib-release
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by-pkgid
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d8a50ad1f2c695175a86b4ac856fd8af
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files
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126
