AntCall Task

## AntCall

### Description

Call another target within the same buildfile optionally specifying some properties (params in this context). This task must not be used outside of a `target`.

By default, all of the properties of the current project will be available in the new project. Alternatively, you can set the inheritAll attribute to `false` and only "user" properties (i.e., those passed on the command-line) will be passed to the new project. In either case, the set of properties passed to the new project will override the properties that are set in the new project (See also the property task).

You can also set properties in the new project from the old project by using nested param tags. These properties are always passed to the new project and any project created in that project regardless of the setting of inheritAll. This allows you to parameterize your subprojects. Properties defined on the command line can not be overridden by nested `<param>` elements.

When more than one nested `<param>` element would set a property of the same name, the one declared last will win. This is for backwards compatibility reasons even so it is different from the way `<property>` tasks in build files behave.

Nested `<reference>`; elements can be used to copy references from the calling project to the new project, optionally under a different id. References taken from nested elements will override existing references that have been defined outside of targets in the new project - but not those defined inside of targets.

When a target is invoked by antcall, all of its dependent targets will also be called within the context of any new parameters. For example. if the target "doSomethingElse" depended on the target "init", then the antcall of "doSomethingElse" will call "init" during the call. Of course, any properties defined in the antcall task or inherited from the calling target will be fixed and not overridable in the init task--or indeed in the "doSomethingElse" task.

The called target(s) are run in a new project; be aware that this means properties, references, etc. set by called targets will not persist back to the calling project.

If the build file changes after you've started the build, the behavior of this task is undefined.

### Parameters

Attribute | Description | Required
target | The target to execute. | Yes
inheritAll | If `true`, pass all properties to the new Apache Ant project. Defaults to `true`. | No
inheritRefs | If `true`, pass all references to the new Ant project. Defaults to `false`. | No

### Note on `inheritRefs`

`<antcall>` will not override existing references, even if you set `inheritRefs` to true. As the called build files is the same build file as the calling one, this means it will not override any reference set via an `id` attribute at all. The only references that can be inherited by the child project are those defined by nested `<reference>` elements or references defined by tasks directly (not using the `id` attribute).

### Parameters specified as nested elements

#### param

Specifies the properties to set before running the specified target. See property for usage guidelines.
These properties become equivalent to properties you define on the command line. These are special properties and they will always get passed down, even through additional `<*ant*>` tasks with inheritall set to false (see above).

#### reference

Used to choose references that shall be copied into the new project, optionally changing their id.

Attribute | Description | Required
refid | The id of the reference in the calling project. | Yes
torefid | The id of the reference in the new project. | No, defaults to the value of refid.

#### propertyset

You can specify a set of properties to be copied into the new project with propertysets.

since Ant 1.6.

#### target

You can specify multiple targets using nested `<target>` elements instead of using the target attribute. These will be executed as if Ant had been invoked with a single target whose dependencies are the targets so specified, in the order specified.

Attribute | Description | Required
name | The name of the called target. | Yes

since Ant 1.6.3.

### Examples

>     <target name="default">
>       <antcall target="doSomethingElse">
>         <param name="param1" value="value"/>
>       </antcall>
>     </target>

>     <target name="doSomethingElse">
>       <echo message="param1=${param1}"/>
>     </target>

Will run the target 'doSomethingElse' and echo 'param1=value'.

>     <antcall ... >
>       <reference refid="path1" torefid="path2"/>
>     </antcall>

will copy the parent's definition of `path1` into the new project using the id `path2`.