Comment 7. Data Transformation means transforming data from one form to another. Camel Processor is one of the key building blocks, and it gives access to the full message transferred, including body, headers, and properties associated with the message. By creating a processor, you can modify any elements or properties of the message body; for example, you can add custom properties to the header, transforming the message from CSV to XML, etc.
Camel Processor is interface defined in org. Below are the input and output message. In this class, you will see the Camel route has been defined, with the process route calling the MyTransform class, which is actually transforming CSV into an XML message. In the process method, you will get input data as an exchange object. Finally, the transformed message is set as the exchange.
It is very easy to transform one message format into another using Apache Camel. There are different ways provided by Camel to transform the message. Integration Zone. Over a million developers have joined DZone. Let's be friends:.
DZone 's Guide to. Free Resource. Like 7. Join the DZone community and get the full member experience. Join For Free. CamelContext; import org. DefaultCamelContext; import org. Exchange; import org. Employee; import org. Exchange; import java.
StringTokenizer; import org. Exchange; public class CustomProcessorXStream implements org. CustomProcessorXStream; import org. RouteBuilder; import org.
XStreamDataFormat; import com. Employee; import java. HashMap; import java.deenarielo.pw Boot and Apache Camel Integration
Like This Article?The Cron component is a generic interface component that allows triggering events at specific time interval specified using the Unix cron syntax e. Being an interface component, the Cron component does not contain a default implementation, instead it requires that the users plug the implementation of their choice.
The Cron component is also supported in Camel Kwhich can use the Kubernetes scheduler to trigger the routes when required by the cron expression. Camel K does not require additional libraries to be plugged when using cron expressions compatible with Kubernetes cron syntax.
Maven users will need to add the following dependency to their pom. Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.
Whether the component should use basic property binding Camel 2. The id of the CamelCronService to use when multiple implementations are provided. Required A cron expression that will be used to generate events. To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. Sets the exchange pattern when the consumer creates an exchange.
Whether the endpoint should use basic property binding Camel 2. Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing if supported. Schedule expressions can be made of 5 to 7 parts.
When expressions are composed of 6 parts, the first items is the "seconds" part and year is considered missing. When using cron with Spring Boot make sure to use the following Maven dependency to have support for auto configuration:. Whether to enable auto configuration of the cron component. This is enabled by default. Edit this Page. Since Camel 3. Additional libraries may be needed in order to plug a specific implementation.
Options The Cron component supports 3 options, which are listed below. Name Description Default Type bridgeErrorHandler consumer Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. Query Parameters 6 parameters : Name Description Default Type bridgeErrorHandler consumer Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler.
ExceptionHandler exchangePattern consumer Sets the exchange pattern when the consumer creates an exchange. Usage The component can be used to trigger events at specified times, as in the following example:. Spring Boot Auto-Configuration When using cron with Spring Boot make sure to use the following Maven dependency to have support for auto configuration:.
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Name Description Default Type camel. Required The name of the cron trigger.Here the implementation is slightly different with Camel. Spring Boot is an organized Java framework for building microservices based on the Spring Dependency Injection framework with minimal code and configuration and allows packaging them into an isolated executable jar giving you production ready microservices. Apache Camel is a routing engine which provides an implementation for almost all Enterprise Integration Patterns with many different components to facilitate integration with various systems.
Spring Boot Tutorial- Integrate Spring Boot+ Apache Camel
After clicking Nextyou would get Spring starter dependency window. Check the pom. Copy below complete pom. Spring Boot would have created SpringbootCamelRestdslApiApplication bootstrap class with main method to run the application. We will now inject Camel Servlet and Camel route to this class. Camel has made life easier for users w. Note : With Camel version below 2. When we add bindingMode RestBindingMode.
When we add Component to StudentRoute class it tells Camel following class is a route in Spring context and injects it into the available camelContext. The complete main application class will now look as below post adding the camel route. You can also define Camel Route in a separate class with Component annotation.
Check the console tab for application build status. If all is good you should see below screen. In the IDE, right-click the project and select to Run as Maven install to generate executable jar file for your application in project target folder as seen on below screen.
We noticed that there was neither a single line of XML nor a web. This was possible because many components are available in Camel to integrate with different framework and technologies seamlessly.
For readers benefit, above code can be cloned from Github!
Hello and thank you for your useful tutorial.Apache Camel is described on its main web page and in the Camel User Guide as "a versatile open-source integration framework based on known Enterprise Integration Patterns. I look at a "Hello World" type example of using Camel in this post. David Newcomb has described Camel there:. Keeping the example simple makes it clearer how to use Camel. This example uses Camel to transfer files automatically from a specified directory to a different specified directory.
Three cases will be demonstrated. In the first case, files placed in the "input" directory are automatically copied to an "output" directory without affecting the source files.
In the second case, the files placed in the "input" directory are automatically copied to an "output" directory and then the files in the "input" directory are stored in a special ". The third case removes the files from the "input" directory upon copying to the "output" directory effectively a "move" operation. All three cases are implemented with almost identical code. The only difference between the three is in the single line specifying how Camel should handle the file transfers.
The next code listing shows the basic code needed to use Camel to automatically copy files placed in an input directory into a different output directory with Camel. Lines add the Camel route to this instantiated context and line 22 starts the context with line 24 stopping the context.
It's all pretty simple, but the most interesting part to me is the specification of the routing on line Because the instance implementing the RoutesBuilder interface provided to the Camel Context only requires its abstract configure method to be overridden, it is an easy class to instantiate as an anonymous class inline with the call to CamelContext.
This is what I did in the code above and is what is done in many of the Camel examples that are available online. Line 19 shows highly readable syntax describing "from" and "to" portions of routing.
In this case, files placed in the input directory "from" are to be copied to the output directory "to". The "file" protocol is used on both the "from" and "to" portions because the file system is where the "message" is coming from and going to. The "? As just mentioned, Line 19 in the code above instructs Camel to copy files already in or placed in the "input" directory to the specified "output" directory without impacting the files in the "input" directory.
In some cases, I may want to "move" the files rather than "copying" them. In such cases,? In other words, line 19 above could be replaced with this to have files removed from the "input" directory when placed in the "output" directory. If no parameter is designated on the input neither?
The three cases are highlighted next. Camel implements this via implementation inheritance methods like "from" and "to" are defined in the RouteBuilder class rather than through static imports an approach often used for Java-based DSLs. Although it is common to pass anonymous instances of RouteBuilder to the Camel Context, this is not a requirement. There can be situations in which it is advantageous to have standalone classes that extend RouteBuilder and have instances of those extended classes passed to the Camel Context.
I'll use this approach to demonstrate all three cases I previously described. The next code listing shows a class that extends RouteBuilder. In many cases, I would have a no-arguments constructor, but in this case I use the constructor to determine which type of file transfer should be supported by the Camel route.
The next code listing shows a named standalone class that handles all three cases shown above copying, copying with archiving of input files, and moving.
This single extension of RouteBuilder takes an enum in its constructor to determine how to configure the input endpoint. This blog post has demonstrated use of Camel to easily route files from one directory to another.
Camel supports numerous other transport mechanisms and data formats that are not shown here.
Hello Camel: Automatic File Transfer
This post focused on what is likely to be as simplest possible example of how to apply Camel in a useful manner, but Camel supports far more than shown in this simple example. Dustin Marx is a principal software engineer and architect at Raytheon Company.Last Updated on March 21, This post demonstrates a basic use-case for using Apache Camel with Spring Boot — copy a file to another directory.
This basic example enables you to understand other concepts. End-points are just either sources or destination of data. Apache Camel is a rule-based routing and mediation engine that provides a Java object -based implementation of the Enterprise Integration Patterns using an API or declarative Java Domain Specific Language to configure routing and mediation rules. Then, we add a route to it. Think of the route as a rule. See the next code snippet, MyRouterBuilder. Hence, the same file will be copied to the out directory.
I am writing an application where i need to transfer a file from a folder to jms queue. But before that i am trying to transfer the file from one folder to another, which is not happening. On running the application as spring boot application the input folder gets created.
If a paste the file in this folder, the destination folder is not formed and the log statements are also not appearing. This is how I added the route:. It should work, and it does work for me, perhaps you haven't refreshed your workspace in your IDE, if that's how you're tracking the progress.
I see now what's wrong with your configuration - you probably don't have spring-boot-starter-web on your classpath so your main method does not get blocked and exits instantly.
You should remove the main method from CamelApplication and add this entry to application. Alternatively, you can add this to your pom. Learn more. Apache camel copy file between directories Ask Question.
Asked 3 years, 8 months ago. Active 3 years, 8 months ago. Viewed 4k times. Megan Megan 2 2 gold badges 5 5 silver badges 18 18 bronze badges. Active Oldest Votes. EDIT I see now what's wrong with your configuration - you probably don't have spring-boot-starter-web on your classpath so your main method does not get blocked and exits instantly.
I added the dependency for spring-boot-starter-web and it worked. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name.I had assumed that reading from and writing to files in Apache Camel v2. Turns out I was wrong. It took me quite a while to figure out the correct syntax of the from and to commands.
There are various ways to read files in Apache Camel. If the files are in plain text format the org. The from method is overloaded:. The RouteBuilder is closely linked with the org. RouteDefinition class. Unfortunately, the API docs are not explaining a lot.
What happens when we execute this code? Actually nothing.
The code is executed, but nothing is written to the output directory. No exceptions are thrown, not even a warning message is logged. Not quite what we expected, right? Now, being naive again, we look up the Wikipedia article on file URI schemes. Still does not work. Again, no exception, no warning messages. Do we need a third slash, i. Nope, still no success. Maybe double backslashes in file paths are not properly parsed?
Next try:. Same result again. This is getting frustrating. Looking up the website for the Java DSL docs does not give a clear hint neither.
And finally, there exists this documentation on the File2 componentwhich you need to read very carefully to figure out the proper syntax.
If you look around a little you may even find the complete book Apache Camel in Action on the internet, nevertheless things stay obscure. Fast forward. The trick is to specify the filename as a separate parameter added at the end of the directory path.