[[bean-component]]
= Bean Component
//THIS FILE IS COPIED: EDIT THE SOURCE FILE:
:page-source: components/camel-bean/src/main/docs/bean-component.adoc
:docTitle: Bean
:artifactId: camel-bean
:description: Invoke methods of Java beans stored in Camel registry.
:since: 1.0
:supportLevel: Stable
:component-header: Only producer is supported
:core:
include::{cq-version}@camel-quarkus:ROOT:partial$reference/components/bean.adoc[opts=optional]

*Since Camel {since}*

*{component-header}*

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 4 options, which are listed below.



[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *cache* (producer) | *Deprecated* Use singleton option instead. | true | Boolean
| *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
| *scope* (producer) | Scope of bean. When using singleton scope (default) the bean is created or looked up only once and reused for the lifetime of the endpoint. The bean should be thread-safe in case concurrent threads is calling the bean at the same time. When using request scope the bean is created or looked up once per request (exchange). This can be used if you want to store state on a bean while processing a request and you want to call the same bean instance multiple times while processing the request. The bean does not have to be thread-safe as the instance is only called from the same request. When using delegate scope, then the bean will be looked up or created per call. However in case of lookup then this is delegated to the bean registry such as Spring or CDI (if in use), which depends on their configuration can act as either singleton or prototype scope. so when using prototype then this depends on the delegated registry. There are 3 enums and the value can be one of: Singleton, Request, Prototype | Singleton | BeanScope
| *autowiredEnabled* (advanced) | Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc. | true | 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 (5 parameters):


[width="100%",cols="2,5,^1,2",options="header"]
|===
| Name | Description | Default | Type
| *cache* (common) | *Deprecated* Use scope option instead. |  | Boolean
| *method* (common) | Sets the name of the method to invoke on the bean |  | String
| *scope* (common) | Scope of bean. When using singleton scope (default) the bean is created or looked up only once and reused for the lifetime of the endpoint. The bean should be thread-safe in case concurrent threads is calling the bean at the same time. When using request scope the bean is created or looked up once per request (exchange). This can be used if you want to store state on a bean while processing a request and you want to call the same bean instance multiple times while processing the request. The bean does not have to be thread-safe as the instance is only called from the same request. When using prototype scope, then the bean will be looked up or created per call. However in case of lookup then this is delegated to the bean registry such as Spring or CDI (if in use), which depends on their configuration can act as either singleton or prototype scope. so when using prototype then this depends on the delegated registry. There are 3 enums and the value can be one of: Singleton, Request, Prototype | Singleton | BeanScope
| *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
| *parameters* (advanced) | Used for configuring additional properties on the bean |  | Map
|===
// endpoint 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
https://www.javadoc.io/doc/org.apache.camel/camel-bean/current/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.


include::{page-component-version}@camel-spring-boot::page$bean-starter.adoc[]
