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<title>Include Task</title>
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<h2><a name="include">Include</a></h2>
<h3>Description</h3>
<p>
Include another build file into the current project.
</p>
<p><em>since Apache Ant 1.8.0</em></p>
<p>
<b>Note</b> this task heavily relies on the ProjectHelper
implementation and doesn't really perform any work of its own. If
you have configured Ant to use a ProjectHelper other than Ant's
default, this task may or may not work.
</p>
<p>
On execution it will read another Ant file into the same Project
rewriting the included target names and depends lists. This is
different
from <a href="http://ant.apache.org/faq.html#xml-entity-include">Entity
Includes as explained in the Ant FAQ</a> insofar as the target
names get prefixed by the included project's name or the as
attribute and do not appear as if the file was contained in the
including file.
</p>
<p>
The include task may only be used as a top-level task. This means that
it may not be used in a target.
</p>
<p>
There are two further functional aspects that pertain to this task and
that are not possible with entity includes:
<ul>
<li>target rewriting</li>
<li>special properties</li>
</ul>
</p>
<h4>Target rewriting</h4>
<p>Any target in the included file will be renamed
to <i>prefix.name</i> where <i>name</i> is the original target's
name and <i>prefix</i> is either the value of the <i>as</i>
attribute or the <i>name</i> attribute of the <i>project</i> tag of
the included file.</p>
<p>The depends attribute of all included targets is rewritten so that
all target names are prefixed as well. This makes the included file
self-contained.</p>
<p>Note that prefixes nest, so if a build file includes a file with
prefix "a" and the included file includes another file with prefix
"b", then the targets of that last build file will be prefixed by
"a.b.".</p>
<p><code><import></code> contribute to the prefix as well, but
only if their <code>as</code> attribute has been specified.
<h4>Special Properties</h4>
<p>Included files are treated as they are present in the main
buildfile. This makes it easy to understand, but it makes it impossible
for them to reference files and resources relative to their path.
Because of this, for every included file, Ant adds a property that
contains the path to the included buildfile. With this path, the
included buildfile can keep resources and be able to reference them
relative to its position.</p>
<p>So if I include for example a <i>docsbuild.xml</i> file named <b>builddocs</b>,
I can get its path as <b>ant.file.builddocs</b>, similarly to the <b>ant.file</b>
property of the main buildfile.</p>
<p>Note that "builddocs" is not the filename, but the name attribute
present in the included project tag.</p>
<p>
If the included file does not have a name attribute, the ant.file.projectname
property will not be set.
</p>
<p>If you need to know whether the current build file's source has
been a file or an URL you can consult the
property <b>ant.file.type.<em>projectname</em></b> (using the same
example as above <b>ant.file.type.builddocs</b>) which either have
the value "file" or "url".</p>
<h4>Resolving files against the included file</h4>
<p>Suppose your main build file called <code>including.xml</code>
includes a build file <code>included.xml</code>, located anywhere on
the file system, and <code>included.xml</code> reads a set of
properties from <code>included.properties</code>:</p>
<pre><!-- including.xml -->
<project name="including" basedir="." default="...">
<include file="${path_to_included}/included.xml"/>
</project>
<!-- included.xml -->
<project name="included" basedir="." default="...">
<property file="included.properties"/>
</project>
</pre>
<p>This snippet however will resolve <code>included.properties</code>
against the basedir of <code>including.xml</code>, because the basedir
of <code>included.xml</code> is ignored by Ant. The right way to use
<code>included.properties</code> is:</p>
<pre>
<!-- included.xml -->
<project name="included" basedir="." default="...">
<dirname property="included.basedir" file="${ant.file.included}"/>
<property file="${included.basedir}/included.properties"/>
</project>
</pre>
<p>As explained above <code>${ant.file.included}</code> stores the
path of the build script, that defines the project called
<code>included</code>, (in short it stores the path to
<code>included.xml</code>) and <a
href="dirname.html"><code><dirname></code></a> takes its
directory. This technique also allows <code>included.xml</code> to be
used as a standalone file (without being included in other
project).</p>
<p>The above description only works for included files that actually
are included from files and not from URLs. For files included from
URLs using resources relative to the included file requires you to
use tasks that can work on non-file resources in the first place.
To create a relative resource you'd use something like:</p>
<pre>
<loadproperties>
<url baseUrl="${ant.file.included}"
relativePath="included.properties"/>
</loadproperties>
</pre>
<h3>Parameters</h3>
<table border="1" cellpadding="2" cellspacing="0">
<tbody>
<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">
file
</td>
<td valign="top">
The file to include. If this is a relative file name, the file name will be resolved
relative to the <i>including</i> file. <b>Note</b>, this is unlike most other
ant file attributes, where relative files are resolved relative to ${basedir}.
</td>
<td valign="top" align="center">Yes or a nested resource collection</td>
</tr>
<tr>
<td valign="top">
optional
</td>
<td valign="top">
If true, do not stop the build if the file does not exist,
default is false.
</td>
<td valign="top" align="center">No</td>
</tr>
<tr>
<td valign="top">
as
</td>
<td valign="top">
Specifies the prefix prepended to the target names. If
omitted, the name attribute of the project tag of the
included file will be used.
</td>
<td valign="top" align="center">Yes, if the included file's
project tag doesn't specify a name attribute.</td>
</tr>
<tr>
<td valign="top">
prefixSeparator
</td>
<td valign="top">
Specifies the separator to be used between the prefix and the
target name. Defaults to ".".
</td>
<td valign="top" align="center">No</td>
</tr>
</tbody>
</table>
<h3>Parameters specified as nested elements</h3>
<h4>any <a href="../Types/resources.html">resource</a> or resource
collection</h4>
<p>The specified resources will be included.</p>
<h3>Examples</h3>
<pre> <include file="../common-targets.xml"/>
</pre>
<p>Includes targets from the common-targets.xml file that is in a parent
directory.</p>
<pre> <include file="${deploy-platform}.xml"/>
</pre>
<p>Includes the project defined by the property deploy-platform</p>
<pre>
<include>
<javaresource name="common/targets.xml">
<classpath location="common.jar"/>
</javaresource>
</include>
</pre>
<p>Includes targets from the targets.xml file that is inside the
directory common inside the jar file common.jar.</p>
<h3>How is <a href="import.html"><import></a> different
from <include>?</h3>
<p>The short version: Use import if you intend to override a target,
otherwise use include.</p>
<p>When using import the imported targets are available by up to two
names. Their "normal" name without any prefix and potentially with
a prefixed name (the value of the as attribute or the imported
project's name attribute, if any).</p>
<p>When using include the included targets are only available in the
prefixed form.</p>
<p>When using import, the imported target's depends attribute
remains unchanged, i.e. it uses "normal" names and allows you to
override targets in the dependency list.</p>
<p>When using include, the included targets cannot be overridden and
their depends attributes are rewritten so that prefixed names are
used. This allows writers of the included file to control which
target is invoked as part of the dependencies.</p>
<p>It is possible to include the same file more than once by using
different prefixes, it is not possible to import the same file more
than once.</p>
<h4>Examples</h4>
<p><i>nested.xml</i> shall be:</p>
<pre>
<project>
<target name="setUp">
<property name="prop" value="in nested"/>
</target>
<target name="echo" depends="setUp">
<echo>prop has the value ${prop}</echo>
</target>
</project>
</pre>
<p>When using import like in</p>
<pre>
<project default="test">
<target name="setUp">
<property name="prop" value="in importing"/>
</target>
<import file="nested.xml" as="nested"/>
<target name="test" depends="nested.echo"/>
</project>
</pre>
<p>Running the build file will emit:
<pre>
setUp:
nested.echo:
[echo] prop has the value in importing
test:
</pre>
<p>When using include like in</p>
<pre>
<project default="test">
<target name="setUp">
<property name="prop" value="in importing"/>
</target>
<include file="nested.xml" as="nested"/>
<target name="test" depends="nested.echo"/>
</project>
</pre>
<p>Running the target build file will emit:
<pre>
nested.setUp:
nested.echo:
[echo] prop has the value in nested
test:
</pre>
<p>and there won't be any target named "echo" on the including build file.</p>
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