Apache Camel Dynamic Router Pattern in Apache Camel using example

In previous tutorial we implemented the Routing Slip EIP Pattern
In this tutorial we will implement the Dynamic Router EIP.
The Dynamic Router from the EIP patterns allows you to route messages while avoiding the dependency of the router on all possible destinations while maintaining its efficiency.

Apache Camel - Table of Contents
File Transfer Using Java DSL Apache Camel
Apache Camel Java DSL + Spring Integration Hello World Example
Apache Camel Exception Handling Using Simple Example
Apache Camel Redelivery policy using example
Integrate Apache Camel and ActiveMQ
EIP patterns using Apache Camel
Apache Camel Tutorial- Integrate Spring Boot+ Apache Camel
Apache Camel Tutorial- Integrate with MySQL DB using SQL query
Apache Camel + Spring + ActiveMQ + JBoss Fuse 
Apache Camel EIP - Splitter and Aggregator pattern
Apache Camel Unit Testing 
Apache Camel + Spring + Quartz Hello World Example 
Camel application deployment on JBoss Fuse 
Apache Camel + Apache CXF SOAP Webservices
Apache Camel + JAX-RS REST Webservice
Apache Camel + CXFRS REST Webservice 
Apache Camel Routing Slip EIP Pattern
Apache Camel Dynamic Router Pattern
Apache Camel Load Balancer EIP Pattern
Apache Camel Interceptors
Apache Camel + Kafka Hello World Example
Apache Camel - Marshalling/Unmarshalling XML/JSON Data Example
Calling and Consuming Webservices using Apache Camel
Apache Camel Tutorial - Send SMTP Email Using Gmail
Apache Camel Tutorial - SEDA component Hello World Example
Spring Boot + Apache Camel + RabbitMQ - Hello World Example
Apache Camel Tutorial - Idempotent Consumer using MemoryIdempotentRepository and FileIdempotentRepository
Spring Boot + Apache Camel JDBC component + MySQL - Hello World Example 
Spring Boot + Apache Camel SQL component + MySQL - Hello World Example
Spring Boot + Apache Camel SQL component + Transaction Management Example

Lets Begin

We will create Eclipse maven project as follows-


Our pom file will be as follows-

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>com.javainuse</groupId>
	<artifactId>camel-dynamic-router</artifactId>
	<version>0.0.1-SNAPSHOT</version>

	<dependencies>
		<dependency>
			<groupId>org.apache.camel</groupId>
			<artifactId>camel-core</artifactId>
			<version>2.13.0</version>
		</dependency>
	</dependencies>
</project>

Define the route.

package com.javainuse;

import org.apache.camel.Exchange;
import org.apache.camel.Processor;
import org.apache.camel.builder.RouteBuilder;

public class SimpleRouteBuilder extends RouteBuilder {

	@Override
	public void configure() throws Exception {

		from("file:C:/inbox?noop=true").split().tokenize("\n").dynamicRouter(method(DynamicRouterBean.class, "route"));

		from("direct:route1").process(new Processor() {
			public void process(Exchange exchange) {
				String body = exchange.getIn().getBody().toString();
				body = body + " in route 1";
				System.out.println(body);
				exchange.getIn().setBody(body);
			}
		});

		from("direct:route2").process(new Processor() {
			public void process(Exchange exchange) {
				String body = exchange.getIn().getBody().toString();
				body = body + " in route 2";
				System.out.println(body);
				exchange.getIn().setBody(body);
			}
		});

		from("direct:route3").process(new Processor() {
			public void process(Exchange exchange) {
				String body = exchange.getIn().getBody().toString();
				body = body + " in route 3";
				exchange.getIn().setBody(body);
				System.out.println(body);
			}
		});
	}
}

In the below example using the dynamic router we define the sequence of the routes depending on their body message -
Dynamic Router will set a property (Exchange.SLIP_ENDPOINT) on the Exchange which contains the current endpoint as it advanced though the slip. This allows you to know how far we have processed in the slip. (It's a slip because the Dynamic Router implementation is based on top of Routing Slip).

package com.javainuse;

import org.apache.camel.Exchange;
import org.apache.camel.Header;

public class DynamicRouterBean {
	public String route(String body, @Header(Exchange.SLIP_ENDPOINT) String previousRoute) {
		if (previousRoute == null) {
			return "direct://route3";
			// check the body content and decide route
		} else if (body.toString().equals("javainuse in route 3")) {
			return "direct://route2";
			// check the body content and decide route
		} else if (body.toString().equals("javainuse in route 3 in route 2")) {
			return "direct://route1";
		} else {
			return null;
		}
	}
}

When Camel is started, it creates a CamelContext object that contains the definition of the Route to be started. Below we create default camel context and load the routes created in SimpleRouteBuilder.

package com.javainuse;

import org.apache.camel.CamelContext;
import org.apache.camel.impl.DefaultCamelContext;

public class MainApp {

    public static void main(String[] args) {
        SimpleRouteBuilder routeBuilder = new SimpleRouteBuilder();
        CamelContext ctx = new DefaultCamelContext();
        try {
            ctx.addRoutes(routeBuilder);
            ctx.start();
            Thread.sleep(5 * 60 * 1000);
            ctx.stop();
        }
        catch (Exception e) {
            e.printStackTrace();
        }

    }
}

Next run the MainApp class as a java application-

Download Source Code

Download it - Apache Camel Routing Slip EIP Pattern

See Also
Spring Boot Hello World Application- Create simple controller and jsp view using Maven
Spring Boot Tutorial-Spring Data JPA
Spring Boot + Simple Security Configuration
Pagination using Spring Boot Simple Example
Spring Boot + ActiveMQ Hello world Example
Spring Boot + Swagger Example Hello World Example
Spring Boot + Swagger- Understanding the various Swagger Annotations
Spring Boot Main Menu
Spring Boot Interview Questions