Set Up a Java Project for DMN

Now you are ready to set up your first process application project in the IDE of your choice (for example IntelliJ IDEA, Eclipse, or VS Code).

Terminology: processes vs. decisions

DMN is a modeling language for decisions, whereas BPMN is a language for processes. This tutorial focuses on decisions. However, the Java project contains classes and files with names like ProcessApplication and processes.xml. These are generally applicable and can be used with both processes and decisions.

Create a new Maven project

Create a new Maven project named dinner-dmn. Use your IDE’s New Maven Project wizard — choose a simple project and skip the archetype selection. Since you are setting up a WAR project, set Packaging to war. You can also create the project directly from the pom.xml shown below.

Add ASEE Flow Maven dependencies

The next step consists of setting up the Maven dependencies for your new process application. Add the following dependencies to the pom.xml file of your project:

<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>org.aseeflow.bpm.getstarted</groupId>
  <artifactId>dinner-dmn</artifactId>
  <version>0.1.0-SNAPSHOT</version>
  <packaging>war</packaging>

  <properties>
    <aseeflow.version>1.0.0</aseeflow.version>
    <maven.compiler.release>11</maven.compiler.release>
  </properties>

  <dependencyManagement>
    <dependencies>
      <dependency>
        <groupId>org.aseeflow.bpm</groupId>
        <artifactId>aseeflow-bom</artifactId>
        <version>${aseeflow.version}</version>
        <scope>import</scope>
        <type>pom</type>
      </dependency>
    </dependencies>
  </dependencyManagement>

  <dependencies>
    <dependency>
      <groupId>org.aseeflow.bpm</groupId>
      <artifactId>aseeflow-engine</artifactId>
      <scope>provided</scope>
    </dependency>

    <dependency>
      <groupId>jakarta.servlet</groupId>
      <artifactId>jakarta.servlet-api</artifactId>
      <version>6.0.0</version>
      <scope>provided</scope>
    </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.11.0</version>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-war-plugin</artifactId>
        <version>3.3.2</version>
        <configuration>
          <failOnMissingWebXml>false</failOnMissingWebXml>
        </configuration>
      </plugin>
    </plugins>
  </build>

</project>

Now you can perform the first build. Select the pom.xml in the Package Explorer, right-click, and select Run As > Maven Install.

Catch up: get the sources of Step-1

git clone https://github.com/aseeflow/aseeflow-get-started-dmn.git
git checkout -f Step-1

Or download as a .zip.

Add a process application class

Next, create a package — for example org.camunda.bpm.getstarted.dmn — and add a process application class to it. The process application class constitutes the interface between your application and the process engine.

package org.camunda.bpm.getstarted.dmn;

import org.camunda.bpm.application.ProcessApplication;
import org.camunda.bpm.application.impl.ServletProcessApplication;

@ProcessApplication("Dinner App DMN")
public class DinnerApplication extends ServletProcessApplication
{
  //empty implementation
}

Add a META-INF/processes.xml deployment descriptor

The last step to set up the process application is to add the META-INF/processes.xml deployment descriptor file. This file lets you provide a declarative configuration of the deployment(s) this process application makes to the process engine. This file needs to be added to the src/main/resources/META-INF folder of the Maven project.

<?xml version="1.0" encoding="UTF-8" ?>

<process-application
    xmlns="http://www.camunda.org/schema/1.0/ProcessApplication"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

  <process-archive name="dinner-dmn">

    <process-engine>default</process-engine>
    <properties>
      <property name="isDeleteUponUndeploy">false</property>
      <property name="isScanForProcessDefinitions">true</property>
    </properties>
  </process-archive>

</process-application>

At this point you have successfully set up the process application, and you can start modeling your first decision table.

Catch up: get the sources of Step-2

git clone https://github.com/aseeflow/aseeflow-get-started-dmn.git
git checkout -f Step-2

Or download as a .zip.

Next step

Continue to create a decision table.

​Terminology: processes vs. decisions

​Create a new Maven project

​Add ASEE Flow Maven dependencies

​Add a process application class

​Add a META-INF/processes.xml deployment descriptor

​Next step

Terminology: processes vs. decisions

Create a new Maven project

Add ASEE Flow Maven dependencies

Add a process application class

Add a META-INF/processes.xml deployment descriptor

Next step