components/camel-mapstruct/src/main/docs/mapstruct-component.adoc

= MapStruct Component
:doctitle: MapStruct
:shortname: mapstruct
:artifactid: camel-mapstruct
:description: Type Conversion using Mapstruct
:since: 3.19
:supportlevel: Stable
:tabs-sync-option:
:component-header: Only producer is supported
//Manually maintained attributes
:camel-spring-boot-name: mapstruct

*Since Camel {since}*

*{component-header}*

The camel-mapstruct component is used for converting POJOs using https://mapstruct.org/[MapStruct].

== URI format

----
mapstruct:className[?options]
----

Where `className` is the fully qualified class name of the POJO to convert to.

// component-configure options: START

// component-configure options: END

// component options: START
include::partial$component-configure-options.adoc[]
include::partial$component-endpoint-options.adoc[]
// component options: END

// endpoint options: START

// endpoint options: END
// component headers: START
include::partial$component-endpoint-headers.adoc[]
// component headers: END

== Setting up MapStruct

The camel-mapstruct component must be configured with one or more package names, for classpath scanning MapStruct _Mapper_ classes.
This is needed because the _Mapper_ classes are to be used for converting POJOs with MapStruct.

For example to set up two packages you can do as following:

[source,java]
----
MapstructComponent mc = context.getComponent("mapstruct", MapstructComponent.class);
mc.setMapperPackageName("com.foo.mapper,com.bar.mapper");
----

This can also be configured in `application.properties`:

[source,properties]
----
camel.component.mapstruct.mapper-package-name = com.foo.mapper,com.bar.mapper
----

Camel will on startup scan these packages for classes which names ends with _Mapper_. These classes
are then introspected to discover the mapping methods. These mapping methods are then registered
into the Camel xref:manual::type-converter.adoc[Type Converter] registry. This means that you can
also use type converter to convert the POJOs with MapStruct, such as:

[source,java]
----
from("direct:foo")
  .convertBodyTo(MyFooDto.class);
----

Where `MyFooDto` is a POJO that MapStruct is able to convert to/from.

NOTE: Camel does not support mapper methods defined with a `void` return type such as those used with `@MappingTarget`.

WARNING: If you define multiple mapping methods for the same from / to types, then the implementation chosen by
Camel to do its type conversion is potentially non-deterministic.

include::spring-boot:partial$starter.adoc[]