If a target in the main file is also present in at least one of the imported files, the one from the main file takes precedence.

So if I import for example a docs/build.xml file named builddocs, that contains a "docs" target, I can redefine it in my main buildfile and that is the one that will be called. This makes it easy to keep the same target name, so that the overriding target is still called by any other targets--in either the main or imported buildfile(s)--for which it is a dependency, with a different implementation. The target from docs/build.xml is made available by the name "builddocs.docs". This enables the new implementation to call the old target, thus enhancing it with tasks called before or after it.

Imported 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 imported file, Phing adds a property that contains the path to the imported buildfile. With this path, the imported buildfile can keep resources and be able to reference them relative to its position.

So if I import for example a docs/build.xml file named builddocs, I can get its path as phing.file.builddocs, similarly to the phing.file property of the main buildfile. Additionally, the directory will be stored in phing.dir.builddocs.

Note that "builddocs" is not the filename, but the name attribute present in the imported project tag.

If import file does not have a name attribute, the phing.file.projectname and phing.dir.projectname properties will not be set.

Suppose your main build file called importing.xml imports a build file imported.xml , located anywhere on the file system, and imported.xml reads a set of properties from imported.properties:

<!-- importing.xml -->
<project name="importing" basedir="." default="...">
<import file="${path_to_imported}/imported.xml"/>
</project>

<!-- imported.xml -->
<project name="imported" basedir="." default="...">
<property file="imported.properties"/>
</project>
        

This snippet however will resolve imported.properties against the basedir of importing.xml , because the basedir of imported.xmlis ignored by Phing. The right way to use imported.properties is:

<!-- imported.xml -->
<project name="imported" basedir="." default="...">
<dirname property="imported.basedir" file="${phing.file.imported}"/>
<property file="${imported.basedir}/imported.properties"/>
</project>
        

or even shorter:

<!-- imported.xml -->
<project name="imported" basedir="." default="...">
<property file="${phing.dir.imported}/imported.properties"/>
</project>
        

As explained above ${phing.file.imported} stores the full path of the build script, that defines the project called imported, (in short it stores the path to imported.xml) and ${phing.dir.imported} stores its directory. This technique also allows imported.xml to be used as a standalone file (without being imported in other project).

<import file="path/to/build.xml"/>
<import file="path/to/build.xml" optional="true"/>
        

Additionally, ImportTask supports Filesets, i.e. you can easily include/exclude one or more files. For more information, seeAppendix D, Core Types.

<import">
    <fileset dir=".">
        <include name="path/to/build.xml" />
    </fileset>
    <filelist dir="." files="path/to/build.xml"/>
</import>