Spring Boot
Available as of Camel 2.15
Spring Boot component provide auto-configuration for the Apache Camel. Our opinionated auto-configuration of the Camel context auto-detects Camel routes available in the Spring context and registers the key Camel utilities (like producer template, consumer template and the type converter) as beans.
Maven users will need to add the following dependency to their pom.xml
for this component:
<dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-spring-boot</artifactId> <version>${camel.version}</version> <!-- use the same version as your Camel core version --> </dependency>
camel-spring-boot
jar comes with the spring.factories
file, so as soon as you add that dependency into your classpath, Spring Boot will automatically auto-configure the Camel for you.
Auto-configured Camel context
The most important piece of functionality provided by the Camel auto-configuration is CamelContext
instance. Camel auto-configuration creates SpringCamelContext
for your and take care of the proper initialization and shutdown of that context. Created Camel context is also registered in the Spring application context (under camelContext
bean name), so you can access it just as the any other Spring bean.
@Configuration public class MyAppConfig { @Autowired CamelContext camelContext; @Bean MyService myService() { return new DefaultMyService(camelContext); } }
Auto-detecting Camel routes
Camel auto-configuration collects all the RoutesBuilder
instances from the Spring context and automatically injects them into the provided CamelContext
. It means that creating new Camel route with the Spring Boot starter is as simple as adding the @Component
annotated class into your classpath:
@Component public class MyRouter extends RouteBuilder { @Override public void configure() throws Exception { from("jms:invoices").to("file:/invoices"); } }
Or creating new route RoutesBuilder
bean in your @Configuration
class:
@Configuration public class MyRouterConfiguration { @Bean RoutesBuilder myRouter() { return new RouteBuilder() { @Override public void configure() throws Exception { from("jms:invoices").to("file:/invoices"); } }; }
Camel properties
Spring Boot auto-configuration automatically connect Spring Boot external configuration (like properties placeholders, OS environment variables or system properties) with the Camel properties support. It basically means that any property defined in application.properties
file:
route.from = jms:invoices
...or set via system property...
java -Droute.to=jms:processed.invoices -jar mySpringApp.jar
...can be used as placeholders in Camel route:
@Component public class MyRouter extends RouteBuilder { @Override public void configure() throws Exception { from("{{route.from}}").to("{{route.to}}"); } }
Custom Camel context configuration
If you would like to perform some operations on CamelContext
bean created by Camel auto-configuration, register CamelContextConfiguration
instance in your Spring context:
@Configuration public class MyAppConfig { ... @Bean CamelContextConfiguration contextConfiguration() { return new CamelContextConfiguration() { @Override void beforeStart(CamelContext context) { // your custom configuration goes here } } } }
Method CamelContextConfiguration#
beforeStart(CamelContext)
will be call just before the Spring starts the auto-configured CamelContext
.
Disabling JMX
To disable JMX of the auto-configured CamelContext
use camel.springboot.jmxEnabled
property (JMX is enabled by default). For example you could add the following property to your application.properties
file:
camel.springboot.jmxEnabled = false
Auto-configured consumer and producer templates
Camel auto-configuration provides a pre-configured ConsumerTemplate
and ProducerTemplate
instances. You can simply inject them into your Spring-managed beans:
@Component public class InvoiceProcessor { @Autowired private ProducerTemplate producerTemplate; @Autowired private ConsumerTemplate consumerTemplate; public void processNextInvoice() { Invoice invoice = consumerTemplate.receiveBody("jms:invoices", Invoice.class); ... producerTemplate.sendBody("netty-http:http://invoicing.com/received/" + invoice.id()); } }
By default consumer and producer templates comes with the endpoint cache sizes equal to 1000. You can change that values via the following Spring properties:
camel.springboot.consumerTemplateCacheSize = 100 camel.springboot.producerTemplateCacheSize = 200