[[commands-registration-annotation]]
= Annotation

ifndef::snippets[:snippets: ../../test/java/org/springframework/shell/docs]

`@Command` annotation when used on a method marks it as a candidate for command registration.
In below example a command `example` is defined.

[source, java, indent=0]
----
include::{snippets}/CommandAnnotationSnippets.java[tag=command-anno-in-method]
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`@Command` annotation can be placed on a class which either defines defaults or shared settings
for `@Command` methods defined in a same class. In below example a command `parent example` is
defined.

[source, java, indent=0]
----
include::{snippets}/CommandAnnotationSnippets.java[tag=command-anno-in-class]
----

Using a `@Command` will not automatically register command targets, instead it is required to use
`@EnableCommand` and/or `@CommandScan` annotations. This model is familiar from other parts
of Spring umbrella and provides better flexibility for a user being inclusive rather than exclusive
for command targets.

You can define target classes using `@EnableCommand`. It will get picked from all _Configuration_
classes.

[source, java, indent=0]
----
include::{snippets}/CommandAnnotationSnippets.java[tag=enablecommand-with-class]
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You can define target classes using `@CommandScan`. It will get picked from all _Configuration_
classes.

TIP: Define `@CommandScan` in Spring Boot `App` class on a top level and it will automatically
scan all command targets from all packages and classes under `App`.

[source, java, indent=0]
----
include::{snippets}/CommandAnnotationSnippets.java[tag=commandscan-no-args]
----