Invoke static custom Java methods in Mule 4

This example demonstrates how to use Mule 4's Java method to invoke a custom static method with 2 arguments. The custom class is reused from this post: Define and consume custom Java methods using Dataweave 2.0 in Mule 4.

Tips when working with custom java classes in Mule 4:

1. Include your custom namespace in mule-artifact.json
2. If you are making references to third party libraries, include them as maven dependencies in pom.xml

This is a simple example using a HTTP Listener to listen for POST requests to http://localhost:8081/list-files2

Define and consume custom Java methods with Dataweave 2.0 in Mule 4

With the introduction of a brand-new Java module in Mule 4, it is now possible to invoke Java classes in a more straightforward manner from the flow or in Dataweave 2.0 itself.

Here is a simple demonstration of file manipulation using custom Java classes and methods in Mule Anypoint Studio 7.1. This step-by-step tutorial shows how to:
1. Create a custom java class to list files recursively for a local or shared network path
2. Invoking this class from Mulesoft Dataweave 2.0 transformations, and filter information.

Pre-requisites:

There is a dependency on apache commons-io, log4j and joda-time as I will be reusing some methods for file manipulation.

You can find the jar file or maven references here:

https://mvnrepository.com/artifact/commons-io/commons-io/2.6
https://mvnrepository.com/artifact/joda-time/joda-time
https://mvnrepository.com/artifact/log4j/log4j

1. Create your Mule project and add maven dependency

Download the apache commons-io jar file, or alternatively include the reference in your maven pom.xml file.

For this example, I am going to include it as a maven dependency. Copy and paste the code below and include it between the dependencies node in pom.xml, before the closing node: