docs/components/modules/ROOT/pages/bean-component.adoc

[[bean-component]]
= Bean Component
:page-source: components/camel-bean/src/main/docs/bean-component.adoc

*Available as of Camel version 1.0*

The Bean component binds beans to Camel message exchanges.

== URI format

[source]
----
bean:beanName[?options]
----

Where *beanID* can be any string which is used to look up the bean in
the Registry

== Options


// component options: START
The Bean component supports 2 options, which are listed below.



[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *cache* (advanced) | If enabled, Camel will cache the result of the first Registry look-up. Cache can be enabled if the bean in the Registry is defined as a singleton scope. |  | Boolean
| *basicPropertyBinding* (advanced) | Whether the component should use basic property binding (Camel 2.x) or the newer property binding with additional capabilities | false | boolean
|===
// component options: END



// endpoint options: START
The Bean endpoint is configured using URI syntax:

----
bean:beanName
----

with the following path and query parameters:

=== Path Parameters (1 parameters):


[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *beanName* | *Required* Sets the name of the bean to invoke |  | String
|===


=== Query Parameters (6 parameters):


[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *cache* (common) | If enabled, Camel will cache the result of the first Registry look-up. Cache can be enabled if the bean in the Registry is defined as a singleton scope. |  | Boolean
| *method* (common) | Sets the name of the method to invoke on the bean |  | String
| *parameters* (common) | Used for configuring additional properties on the bean |  | Map
| *lazyStartProducer* (producer) | Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel's routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. | false | boolean
| *basicPropertyBinding* (advanced) | Whether the endpoint should use basic property binding (Camel 2.x) or the newer property binding with additional capabilities | false | boolean
| *synchronous* (advanced) | Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported). | false | boolean
|===
// endpoint options: END


// spring-boot-auto-configure options: START
== Spring Boot Auto-Configuration

When using Spring Boot make sure to use the following Maven dependency to have support for auto configuration:

[source,xml]
----
<dependency>
  <groupId>org.apache.camel</groupId>
  <artifactId>camel-bean-starter</artifactId>
  <version>x.x.x</version>
  <!-- use the same version as your Camel core version -->
</dependency>
----


The component supports 5 options, which are listed below.



[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *camel.component.bean.basic-property-binding* | Whether the component should use basic property binding (Camel 2.x) or the newer property binding with additional capabilities | false | Boolean
| *camel.component.bean.cache* | If enabled, Camel will cache the result of the first Registry look-up. Cache can be enabled if the bean in the Registry is defined as a singleton scope. |  | Boolean
| *camel.component.bean.enabled* | Whether to enable auto configuration of the bean component. This is enabled by default. |  | Boolean
| *camel.language.bean.enabled* | Whether to enable auto configuration of the bean language. This is enabled by default. |  | Boolean
| *camel.language.bean.trim* | Whether to trim the value to remove leading and trailing whitespaces and line breaks | true | Boolean
|===
// spring-boot-auto-configure options: END

You can append query options to the URI in the following format,
`?option=value&option=value&...`

== Using

The object instance that is used to consume messages must be explicitly
registered with the Registry. For example, if you
are using Spring you must define the bean in the Spring configuration XML file.

You can also register beans manually via Camel's `Registry` with the `bind` method.

Once an endpoint has been registered, you can build Camel routes that
use it to process exchanges.

A *bean:* endpoint cannot be defined as the input to the route; i.e. you
cannot consume from it, you can only route from some inbound message
Endpoint to the bean endpoint as output. So consider
using a *direct:* or *queue:* endpoint as the input.

You can use the `createProxy()` methods on
http://camel.apache.org/maven/current/camel-core/apidocs/org/apache/camel/component/bean/ProxyHelper.html[ProxyHelper]
to create a proxy that will generate exchanges and send them to any
endpoint:

And the same route using Spring DSL:

[source,xml]
----------------------------
<route>
   <from uri="direct:hello">
   <to uri="bean:bye"/>
</route>
----------------------------

== Bean as endpoint

Camel also supports invoking xref:bean-component.adoc[Bean] as an Endpoint. In the
route below:

What happens is that when the exchange is routed to the `myBean` Camel
will use the Bean Binding to invoke the bean. +
 The source for the bean is just a plain POJO:

Camel will use Bean Binding to invoke the
`sayHello` method, by converting the Exchange's In body to the `String`
type and storing the output of the method on the Exchange Out body.

== Java DSL bean syntax

Java DSL comes with syntactic sugar for the xref:bean-component.adoc[Bean]
component. Instead of specifying the bean explicitly as the endpoint
(i.e. `to("bean:beanName")`) you can use the following syntax:

[source,java]
-------------------------------------------------------
// Send message to the bean endpoint
// and invoke method resolved using Bean Binding.
from("direct:start").bean("beanName");

// Send message to the bean endpoint
// and invoke given method.
from("direct:start").bean("beanName", "methodName");
-------------------------------------------------------

Instead of passing name of the reference to the bean (so that Camel will
lookup for it in the registry), you can specify the bean itself:

[source,java]
---------------------------------------------------------------
// Send message to the given bean instance.
from("direct:start").bean(new ExampleBean());

// Explicit selection of bean method to be invoked.
from("direct:start").bean(new ExampleBean(), "methodName");

// Camel will create the instance of bean and cache it for you.
from("direct:start").bean(ExampleBean.class);
---------------------------------------------------------------

== Bean Binding

How bean methods to be invoked are chosen (if they are not specified
explicitly through the *method* parameter) and how parameter values are
constructed from the Message are all defined by the
Bean Binding mechanism which is used throughout
all of the various Bean Integration
mechanisms in Camel.