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The `retrieve` task copies resolved dependencies anywhere you want in your file system.

This is a link:../use/postresolvetask{outfilesuffix}[post resolve task], with all the behaviour and attributes common to all post resolve tasks.

(*__since 1.4__*) This task can even be used to synchronize the destination directory with what should actually be in according to the dependency resolution. This means that by setting `sync="true"`, Ivy will not only copy the necessary files, but it will also remove the files which do not need to be there.

The synchronisation actually consists in deleting all filles and directories in the root destination directory which are not required by the retrieve.

The root destination directory is the the directory denoted by the first level up the first token in the destination pattern.
For instance, for the pattern `lib/[conf]/[artifact].[ext]`, the root will be `lib`.

(*__since 2.3__*) A nested link:https://ant.apache.org/manual/Types/mapper.html[mapper] element can be used to specify more complex filename transformations of the retrieved files. See the examples below.

== Attributes

[options="header",cols="15%,50%,35%"]
|=======
|Attribute|Description|Required
|pattern|The link:../concept{outfilesuffix}#patterns[pattern] to use to copy the dependencies. Make sure to specify a pattern that defines unique filenames for the artifacts.|No. Defaults to `${ivy.retrieve.pattern}`
|ivypattern|the link:../concept{outfilesuffix}#patterns[pattern] to use to copy the Ivy files of dependencies (*__since 1.3__*)|No. Dependency Ivy files are not retrieved by default.
|conf|a comma separated list of the configurations to retrieve|No. Defaults to the configurations resolved by the last resolve call, or `$$*$$` if no resolve was explicitly called
|sync|`true` to synchronize the destination, false to just make a copy (*__since 1.4__*)|No. Defaults to `false`
|type|comma separated list of accepted artifact types (*__since 1.4__*)|No. All artifact types are accepted by default.
|overwriteMode|option to configure when the destination file should be overwritten if it exists (*__since 2.2__*).

Possible values are: +
* `newer`: overwrite the destination file if a more recent one is available (based on timestamp) +
* `different`: overwrite the destination file if the timestamp is different +
* `always`: always overwrite the destination file +
* `never`: never overwrite the destination file +
|No. Defaults to `newer`.
|symlink|`true` to create symbolic links, `false` to copy the artifacts. The destination of the symbolic links depends on the value of the `useOrigin` attribute. +
The implementation of this task relies on Java standard `Files.createSymbolicLink` API and depending on whether or not the underlying filesystem supports symbolic links, creation of such symbolic links may or may not work. +
If this option is set to `true` and symbolic link creation fails, then the retrieve task will attempt to do a regular copy of the artifact which failed symlink creation. (*__since 2.0__*)|No. Defaults to `false`
|[line-through]#symlinkmass#| *__Deprecated since 2.5__* This option is no longer supported or relevant.|No. Defaults to `false`
|settingsRef|A reference to Ivy settings that must be used by this task (*__since 2.0__*)|No, defaults ot `ivy.instance`.
|log|the log setting to use during the resolve and retrieve process. (*__since 2.0__*)

Available options are the same as for link:../use/resolve{outfilesuffix}[resolve] when used to trigger resolve automatically (see link:../use/postresolvetask{outfilesuffix}[postresolvetask]), or the following for the retrieve process only: +
* `default`: the default log settings, where all usual messages are output to the console +
* `quiet`: disable all usual messages, making the whole retrieve process quiet unless errors occur
|No, defaults to `default`.
|pathId|the id of the path to create containing the retrieved artifacts. (*__since 2.3__*)|No. No path is created by default.
|setId|the id of the fileset to create containing the retrieved artifacts. (*__since 2.3__*)|No. No fileset is created by default.
|=======

== Examples

[source,xml]
----
<ivy:retrieve/>
----

Retrieves dependencies using default parameters. This usually retrieves all the dependencies of the last resolve call to a lib directory.

'''

[source,xml]
----
<ivy:retrieve pattern="${lib.dir}/[conf]/[artifact].[ext]"/>
----

Retrieves all dependencies of the last resolve call to a lib directory, dependencies being separated in directories named by configuration, each conf directory containing corresponding artifacts without the revision.
For instance, if the Ivy file declares two configurations default and test, the resulting lib dir could look like this:

[source]
----
lib
  default
    commons-lang.jar
    commons-logging.jar
  test
    junit.jar
----

Note that if a dependency is required in the two configurations, it will be copied in the two directories. The download of the dependency is however only made once at resolve time.

'''

[source,xml]
----
<ivy:retrieve pattern="${lib.dir}/[conf]/[artifact].[ext]" sync="true"/>
----

Same as before, but with synchronisation enabled.

For instance, if the Ivy file declares two configurations default and test, the resulting lib dir could look like this:

[source]
----
lib
  default
    commons-lang.jar
    commons-logging.jar
  test
    junit.jar
----

And now suppose commons-logging is no longer part of the dependencies of the default configuration, then a new call to retrieve will result in:

[source]
----
lib
  default
    commons-lang.jar
  test
    junit.jar
----

With no synchronisation, commons-logging would not have been removed by the call.

'''

[source,xml]
----
<ivy:retrieve pattern="${lib.dir}/[type]/[artifact]-[revision].[ext]" conf="runtime"/>
----

Retrieves only the dependencies of the `runtime`. Dependencies separated in directories named by artifact type. The resulting lib dir could look like this:

[source]
----
lib
  jar
    commons-lang-1.0.jar
    looks-1.1.jar
  source
    looks-1.1.zip
----

'''

[source,xml]
----
<ivy:retrieve pattern="${lib.dir}/[organisation]/[artifact]-[revision].[ext]"/>
----

Retrieves all dependencies of the last resolve call to a lib directory. The `[organisation]` token will get the unmodified organisation value. The resulting lib dir could look like this:

[source]
----
lib
  org.apache
    commons-lang-1.0.jar
  org.junit
    junit-4.1.jar
    junit-4.1.zip
----

[source,xml]
----
<ivy:retrieve pattern="${lib.dir}/[orgPath]/[artifact]-[revision].[ext]"/>
----

Retrieves all dependencies of the last resolve call to a lib directory. The `[orgPath]` token will get a tree structure. The resulting lib dir could look like this:

[source]
----
lib
  org
    apache
      commons-lang-1.0.jar
    junit
      junit-4.1.jar
      junit-4.1.zip
----

'''

[source,xml]
----
<ivy:retrieve organisation="foo" module="bar" inline="true" pattern="${my.install.dir}/[artifact].[ext]"/>
----

Resolves and retrieves the latest version of the module bar and its dependencies in the directory pointed by `${my.install.dir}`.

'''

[source,xml]
----
<ivy:retrieve pattern="lib/[artifact]-[revision].[ext]">
    <firstmatchmapper>
        <globmapper from="lib/*-SNAPSHOT.jar" to="lib/snapshots/*-SNAPSHOT.jar"/>
        <globmapper from="lib/*" to="lib/releases/*"/>
    </firstmatchmapper>
</ivy:retrieve>
----

Retrieves all dependencies of the last resolve call to a lib directory. The jar files with a version equal to `SNAPSHOT` are retrieved in a `snapshots` directory. The other ones are retrieved in a `releases` directory.
