Spring Boot + Apache Camel + Quartz Example
Why use Apache Camel?
Suppose our application is receiving data from multiple sources like queues, file system. This data will need to be transformed and then sent to maybe to a database.
- This will need a lot of custom code for reading the data from multiple sources, transformation and storing.
- Also if in future more sources from which data is to be read are added it will be a lot of changes.
Overview
In this tutorial we will be implementing a Spring Boot + Apache Camel Project. We will be configuring an Apache Camel route for copying files from one folder to another. Also we will be triggering this route using Quartz.
Video Tutorial
Table Of Contents :
Technology Stack
We will be making use of-- Java 1.8
- Camel Spring Boot Starter - 2.17.0
- Camel Quartz - 2.17.0
- Maven
Implementation
Spring Boot + Apache Camel + Quartz implementation
This will be the standard directory layout for maven project structure-
We need to start by creating a Maven pom.xml(Project Object Model) file. The pom.xml file contains the project configuration details.
<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.codeusingjava</groupId>
<artifactId>springboot-camel</artifactId>
<version>0.0.1-SNAPSHOT</version>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.1.RELEASE</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.source.version>1.8</project.source.version>
<project.target.version>1.8</project.target.version>
<camel.version>2.17.3</camel.version>
</properties>
<dependencies>
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-spring-boot</artifactId>
<version></version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-spring</artifactId>
<version></version>
</dependency>
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-core</artifactId>
<version></version>
</dependency>
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-quartz2</artifactId>
<version></version>
</dependency>
</dependencies>
</project>
- Gets triggered using the quartz cron expression which we have defined as gets triggered after 1 minute.
- Move files from folder1 to folder2
package com.codeusingjava;
import org.apache.camel.Exchange;
import org.apache.camel.Processor;
import org.apache.camel.builder.RouteBuilder;
public class FileRouteBuilder extends RouteBuilder {
@Override
public void configure() throws Exception {
from("file:R://folder1?recursive=true&noop=true&scheduler=quartz2&scheduler.cron=0 0/1 * 1/1 * ? *")
.process(new Processor() {
public void process(Exchange exchange) throws Exception {
System.out.println("transferring " + exchange.getIn().getBody());
}
}).to("file:R://folder2");
}
}
package com.codeusingjava;
import org.apache.camel.CamelContext;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
@SpringBootApplication
public class SpringBootHelloWorldApplication {
@Autowired
private CamelContext camelContext;
public static void main(String[] args) {
SpringApplication.run(SpringBootHelloWorldApplication.class, args);
}
@Bean
public FileRouteBuilder fileRouteBuilder() throws Exception {
FileRouteBuilder routeBuilder = new FileRouteBuilder();
camelContext.addRoutes(routeBuilder);
return routeBuilder;
}
}
What is CamelContext?
We cannot run our Camel Application only using the route. We also need the camel context which acts as a runtime system that runs and manages the routes. It is responsible for all managing all aspects of a route.
Start the Spring Boot application. Quartz will trigger the route after 1 minute.
