mirror of
https://github.com/apache/ant.git
synced 2025-05-18 14:04:48 +00:00
afa2b7af9e
git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@273988 13f79535-47bb-0310-9956-ffa450edef68
154 lines
6.9 KiB
HTML
154 lines
6.9 KiB
HTML
<html>
|
|
|
|
<head>
|
|
<meta http-equiv="Content-Language" content="en-us">
|
|
<title>Property Task</title>
|
|
</head>
|
|
|
|
<body>
|
|
|
|
<h2><a name="property">Property</a></h2>
|
|
<h3>Description</h3>
|
|
<p>Sets a property (by name and value), or set of properties (from file or
|
|
resource) in the project. Properties are case sensitive.</p>
|
|
Properties are immutable: whoever sets a property first freezes it for the
|
|
rest of the build; they are most definately not variable.
|
|
<p>There are five ways to set properties:</p>
|
|
<ul>
|
|
<li>By supplying both the <i>name</i> and <i>value</i> attribute.</li>
|
|
<li>By supplying both the <i>name</i> and <i>refid</i> attribute.</li>
|
|
<li>By setting the <i>file</i> attribute with the filename of the property
|
|
file to load. This property file has the format as defined by the file used
|
|
in the class java.util.Properties.</li>
|
|
<li>By setting the <i>resource</i> attribute with the resource name of the
|
|
property file to load. This property file has the format as defined by the
|
|
file used in the class java.util.Properties.</li>
|
|
<li>By setting the <i>environment</i> attribute with a prefix to use.
|
|
Properties will be defined for every environment variable by
|
|
prefixing the supplied name and a period to the name of the variable.</li>
|
|
</ul>
|
|
<p>Although combinations of these ways are possible, only one should be used
|
|
at a time. Problems might occur with the order in which properties are set, for
|
|
instance.</p>
|
|
<p>The value part of the properties being set, might contain references to other
|
|
properties. These references are resolved at the time these properties are set.
|
|
This also holds for properties loaded from a property file.</p>
|
|
<p>A list of predefined properties can be found <a
|
|
href="../using.html#built-in-props">here</a>.</p>
|
|
<h3>Parameters</h3>
|
|
<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">name</td>
|
|
<td valign="top">the name of the property to set.</td>
|
|
<td valign="top" align="center">No</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">value</td>
|
|
<td valign="top">the value of the property.</td>
|
|
<td valign="middle" align="center" rowspan="3">One of these, when using the
|
|
name attribute</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">location</td>
|
|
<td valign="top">Sets the property to the absolute filename of the
|
|
given file. If the value of this attribute is an absolute path, it
|
|
is left unchanged (with / and \ characters converted to the
|
|
current platforms conventions). Otherwise it is taken as a path
|
|
relative to the project's basedir and expanded.</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">refid</td>
|
|
<td valign="top"><a href="../using.html#references">Reference</a> to an object
|
|
defined elsewhere. Only yields reasonable results for references
|
|
to <a href="../using.html#path">PATH like structures</a> or properties.</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">resource</td>
|
|
<td valign="top">the resource name of the property file.</td>
|
|
<td valign="middle" align="center" rowspan="3">One of these, when
|
|
<b>not</b> using the name attribute</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">file</td>
|
|
<td valign="top">the filename of the property file .</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">environment</td>
|
|
<td valign="top">the prefix to use when retrieving environment variables. Thus
|
|
if you specify environment="myenv" you will be able to access OS-specific
|
|
environment variables via property names "myenv.PATH" or
|
|
"myenv.TERM". Note that if you supply a property name with a final
|
|
"." it will not be doubled. ie environment="myenv." will still
|
|
allow access of environment variables through "myenv.PATH" and
|
|
"myenv.TERM". This functionality is currently only implemented
|
|
on select platforms. Feel free to send patches to increase the number of platforms
|
|
this functionality is supported on ;).<br>
|
|
Note also that properties are case sensitive, even if the
|
|
environment variables on your operating system are not, e.g. it
|
|
will be ${env.Path} not ${env.PATH} on Windows 2000.</td>
|
|
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">classpath</td>
|
|
<td valign="top">the classpath to use when looking up a resource.</td>
|
|
<td align="center" valign="top">No</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">classpathref</td>
|
|
<td valign="top">the classpath to use when looking up a resource,
|
|
given as <a href="../using.html#references">reference</a> to a <path> defined
|
|
elsewhere..</td>
|
|
<td align="center" valign="top">No</td>
|
|
</tr>
|
|
<tr>
|
|
<td valign="top">prefix</td>
|
|
<td valign="top">Prefix to apply to properties loaded using <code>file</code>
|
|
or <code>resource</code>. A "." is appended to the prefix if not specified.</td>
|
|
<td align="center" valign="top">No</td>
|
|
</tr>
|
|
</table>
|
|
<h3>Parameters specified as nested elements</h3>
|
|
<h4>classpath</h4>
|
|
<p><code>Property</code>'s <i>classpath</i> attribute is a <a
|
|
href="../using.html#path">PATH like structure</a> and can also be set via a nested
|
|
<i>classpath</i> element.</p>
|
|
<h3>Examples</h3>
|
|
<pre> <property name="foo.dist" value="dist"/></pre>
|
|
<p>sets the property <code>foo.dist</code> to the value "dist".</p>
|
|
<pre> <property file="foo.properties"/></pre>
|
|
<p>reads a set of properties from a file called "foo.properties".</p>
|
|
<pre> <property resource="foo.properties"/></pre>
|
|
<p>reads a set of properties from a resource called "foo.properties".</p>
|
|
<p>Note that you can reference a global properties file for all of your Ant
|
|
builds using the following:</p>
|
|
<pre> <property file="${user.home}/.ant-global.properties"/></pre>
|
|
<p>since the "user.home" property is defined by the Java virtual machine
|
|
to be your home directory. Where the "user.home" property resolves to in
|
|
the file system depends on the operating system version and the JVM implementation.
|
|
On Unix based systems, this will map to the user's home directory. On modern Windows
|
|
variants, this will most likely resolve to the user's directory in the "Documents
|
|
and Settings" folder. Older windows variants such as Windows 98/ME are less
|
|
predictable, as are other operating system/JVM combinations.</p>
|
|
|
|
<pre>
|
|
<property environment="env"/>
|
|
<echo message="Number of Processors = ${env.NUMBER_OF_PROCESSORS}"/>
|
|
<echo message="ANT_HOME is set to = ${env.ANT_HOME}"/>
|
|
</pre>
|
|
<p>reads the system environment variables and stores them in properties, prefixed with "env".
|
|
Note that this only works on <em>select</em> operating systems.
|
|
Two of the values are shown being echoed.
|
|
</p>
|
|
|
|
<hr>
|
|
<p align="center">Copyright © 2000-2003 Apache Software Foundation. All rights
|
|
Reserved.</p>
|
|
</body>
|
|
</html>
|
|
|