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<title>PropertyFile Task</title>
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<h1>PropertyFile</h1>
<p>by</p>
<!-- Names are in alphabetical order, on last name -->
<ul>
<li>Thomas Christen (<a href="mailto:chr@active.ch">chr@active.ch</a>)</li>
<li>Jeremy Mawson (<a href="mailto:jem@loftinspace.com.au">jem@loftinspace.com/au</a>)</li>
</ul>
<hr>
<h2>Table of Contents</h2>
<ul>
<li><a href="#introduction">Introduction</a></li>
<li><a href="#proptask">PropertyFile Task</a></li>
<li><a href="#entryElement">Entry Task</a></li>
</ul>
<hr>
<h2><a name="introduction">Introduction</a></h2>
<p>Ant provides an optional task for editing property files. This is very useful
when wanting to make unattended modifications to configuration files for application
servers and applications. Currently, the task maintains a working property file with
the ability to add properties or make changes to existing ones. However, any comments
are lost.</p>
<hr>
<h2><a name="proptask">PropertyFile Task</a></h2>
<h3>Parameters</h3>
<table border="1" cellpadding="2" cellspacing="0">
<tr>
<td width="12%" valign="top"><b>Attribute</b></td>
<td width="78%" valign="top"><b>Description</b></td>
<td width="10%" valign="top"><b>Required</b></td>
</tr>
<tr>
<td width="12%" valign="top">file</td>
<td width="78%" valign="top">Location of the property file to be edited</td>
<td width="10%" valign="top">Yes</td>
</tr>
<tr>
<td width="12%" valign="top">comment</td>
<td width="78%" valign="top">Header for the file itself</td>
<td width="10%" valign="top">no</td>
</tr>
</table>
<h3>Parameters specified as nested elements</h3>
<h4><a name="entryElement">Entry</a></h4>
<p>Use nested <code><entry></code>
elements to specify actual modifications to the property file itself.</p>
<table border="1" cellpadding="2" cellspacing="0">
<tr>
<td valign="top"><b>Attribute</b></td>
<td valign="top"><b>Description</b></td>
<td align="center" valign="top"><b>Required</b></td>
</tr>
<tr>
<td valign="top">key</td>
<td valign="top">Name of the property name/value pair</td>
<td valign="top" align="center">Yes</td>
</tr>
<tr>
<td valign="top">value</td>
<td valign="top">Value to set (=), to add (+) or subtract (-)</td>
<td valign="top" align="center" rowspan="2">At least one must be specified</td>
</tr>
<tr>
<td valign="top">default</td>
<td valign="top">Initial value to set for a property if it is not
already defined in the property file.<br>
For type date, an additional keyword is allowed: "now"</td>
</tr>
<tr>
<td valign="top">type</td>
<td valign="top">Regard the value as : int, date or string (default)</td>
<td valign="top" align="center">No</td>
</tr>
<tr>
<td valign="top">operation</td>
<td valign="top">"+" or "=" (default) for all datatypes<br>"-" (for date and int only).<br>
</td>
<td valign="top" align="center">No</td>
</tr>
<tr>
<td valign="top">pattern</td>
<td valign="top">For int and date type only. If present, Values will
be parsed and formatted accordingly.</td>
<td valign="top" align="center">No</td>
</tr>
<tr>
<td valign="top">unit</td>
<td valign="top">The unit of the value to be applied to date +/- operations.
Valid Values are:
<ul>
<li>millisecond</li>
<li>second</li>
<li>minute</li>
<li>hour</li>
<li>day (default)</li>
<li>week</li>
<li>month</li>
<li>year</li>
</ul>
This only applies to date types using a +/- operation.
</td>
<td align="center" valign="top">No</td>
</tr>
</table>
<p>The rules used when setting a property value are shown below. The
operation occurs <b>after</b> these rules are considered.</p>
<ul>
<li>If only value is specified, the property is set to it regardless of its
previous value.</li>
<li>If only default is specified and the property previously existed in the
property file, it is unchanged.</li>
<li>If only default is specified and the property did not exist in the
property file, the property is set to default.</li>
<li>If value and default are both specified and the property previously
existed in the property file, the property is set to value.</li>
<li>If value and default are both specified and the property did not exist in
the property file, the property is set to default.</li>
</ul>
<p> </p>
<h3>Examples</h3>
<p>The following changes the my.properties file. Assume my.properties look like:</p>
<pre># A comment
akey=novalue</pre>
<p>After running, the file would now look like
</p>
<pre>#Thu Nov 02 23:41:47 EST 2000
akey=avalue
adate=2000/11/02 23\:41
anint=1
formated.int=0014
formated.date=028 17\:34
</pre>
<p>
The slashes conform to the expectations of the Properties class. The file will be stored in a manner so that each character is examined and escaped if necessary. Note that the original comment is now lost. Please keep this in mind when running this task against heavily commented properties files. It may be best to have a commented version in the source tree, copy it to a deployment area, and then run the modifications on the copy. Future versions of PropertyFile will hopefully eliminate this shortcoming.
</p>
<blockquote><pre><propertyfile
file="my.properties"
comment="My properties">
<entry key="akey" value="avalue"/>
<entry key="adate" type="date" value="now"/>
<entry key="anint" type="int" operation="+"/>
<entry key="formated.int" type="int" default="0013" operation="+" pattern="0000"/>
<entry key="formated.date" type="date" value="now" pattern="DDD HH:mm"/>
</propertyfile>
</pre></blockquote>
<p>
To produce dates relative from today :</p>
<blockquote><pre><propertyfile
file="my.properties"
comment="My properties">
<entry key="formated.date-1"
type="date" default="now" pattern="DDD"
operation="-" value="1"/>
<entry key="formated.tomorrow"
type="date" default="now" pattern="DDD"
operation="+" value="1"/>
</propertyfile>
</pre></blockquote>
<p>
Concatenation of strings :</p>
<blockquote><pre><propertyfile
file="my.properties"
comment="My properties">
<entry key="progress" default="" operation="+" value="."/>
</propertyfile>
</pre></blockquote>
<p>Each time called, a "." will be appended to "progress"
</p>
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