External Jar Class in Dataweave

We can reuse the existing External Jar Class in Dataweave without writing the java code in dataweave again. One of the external jar usage can be extending StringUtils method in Dataweave as currently Dataweave doesn’t support all the String functions as Java StringUtils does

To do so we have to perform following steps

Add required dependency and shared lib tags in pom.xml

Dependency

<dependency>
	<groupId>org.apache.commons</groupId>
	<artifactId>commons-lang3</artifactId>
	<version>3.10</version>
</dependency>

Shared Library

<configuration>
	<sharedLibraries>
		<sharedLibrary>
			<groupId>org.apache.commons</groupId>
			<artifactId>commons-lang3</artifactId>
		</sharedLibrary>
	</sharedLibraries>
</configuration>

Pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<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/maven-v4_0_0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.mycompany</groupId>
	<artifactId>dataweave-sample</artifactId>
	<version>1.0.0-SNAPSHOT</version>
	<packaging>mule-application</packaging>

	<name>dataweave-sample</name>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>

		<app.runtime>4.2.2</app.runtime>
		<mule.maven.plugin.version>3.3.5</mule.maven.plugin.version>
	</properties>

	<build>
		<plugins>
			<plugin>
				<groupId>org.mule.tools.maven</groupId>
				<artifactId>mule-maven-plugin</artifactId>
				<version>${mule.maven.plugin.version}</version>
				<extensions>true</extensions>
				<configuration>
					<sharedLibraries>
						<sharedLibrary>
							<groupId>org.apache.commons</groupId>
							<artifactId>commons-lang3</artifactId>
						</sharedLibrary>					
					</sharedLibraries>
				</configuration>
			</plugin>
		</plugins>
	</build>

	<dependencies>
		<dependency>
			<groupId>org.mule.connectors</groupId>
			<artifactId>mule-http-connector</artifactId>
			<version>1.5.11</version>
			<classifier>mule-plugin</classifier>
		</dependency>
		<dependency>
			<groupId>org.mule.connectors</groupId>
			<artifactId>mule-sockets-connector</artifactId>
			<version>1.1.5</version>
			<classifier>mule-plugin</classifier>
		</dependency>
		<dependency>
			<groupId>org.apache.commons</groupId>
			<artifactId>commons-lang3</artifactId>
			<version>3.10</version>
		</dependency>
	</dependencies>

	<repositories>
		  <repository>
			<id>anypoint-exchange-v2</id>
			<name>Anypoint Exchange</name>
			<url>https://maven.anypoint.mulesoft.com/api/v2/maven</url>
			<layout>default</layout>
		</repository>
		<repository>
			<id>mulesoft-releases</id>
			<name>MuleSoft Releases Repository</name>
			<url>https://repository.mulesoft.org/releases/</url>
			<layout>default</layout>
		</repository>
	</repositories>
	<pluginRepositories>
		<pluginRepository>
			<id>mulesoft-releases</id>
			<name>mulesoft release repository</name>
			<layout>default</layout>
			<url>https://repository.mulesoft.org/releases/</url>
			<snapshots>
				<enabled>false</enabled>
			</snapshots>
		</pluginRepository>
	</pluginRepositories>
</project>

Add classLoaderModelLoaderDescriptor element in

mule-artifact.json

{
	"minMuleVersion": "4.2.2",
	"classLoaderModelLoaderDescriptor": {
		"id": "mule",
		"attributes": {
			"exportedPackages": [
			"org.apache.commons.lang3"
			]
		}
	}
}

Import the Class and use it in Dataweave

Dataweave

%dw 2.0
import java!org::apache::commons::lang3::StringUtils
output application/json
---
{
	a: StringUtils::substring("MYSTRING",1,2)
}

or

%dw 2.0
output application/json
---
{
	a: java!org::apache::commons::lang3::StringUtils::substring("MYSTRING",1,2)
}

Sample Application – dataweave-sample