java.lang.NoClassDefFoundError when starting process engine

[ericsnyder]

I am trying to get Activiti and Vaadin working together so I can "play" with the two with some simple code and learn. I have added the following dependencies to Maven:

<repositories>
    <repository>
    <id>Alfresco Maven Repository</id>
    <url>https://maven.alfresco.com/nexus/content/groups/public/</url>
  </repository>
  </repositories>
  <dependencies>
  <dependency>
  <groupId>org.activiti</groupId>
  <artifactId>activiti-engine</artifactId>
  <version>5.12</version>
</dependency>
</dependencies>

My code looks like this:

package com.example.testingvaadin;

import org.activiti.engine.*;

import com.vaadin.server.VaadinRequest;
import com.vaadin.ui.Button;
import com.vaadin.ui.Button.ClickEvent;
import com.vaadin.ui.Label;
import com.vaadin.ui.UI;
import com.vaadin.ui.VerticalLayout;

/**
 * Main UI class
 */
@SuppressWarnings("serial")
public class TestingvaadinUI extends UI {

   @Override
   protected void init(VaadinRequest request) {
      ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
      final VerticalLayout layout = new VerticalLayout();
      layout.setMargin(true);
      setContent(layout);

      Button button = new Button("Hello");
      button.addClickListener(new Button.ClickListener() {
         public void buttonClick(ClickEvent event) {
            layout.addComponent(new Label("Thank you for clicking"));
         }
      });
      layout.addComponent(button);
   }
   

}‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

I am getting the following error:

java.lang.NoClassDefFoundError: org/activiti/engine/ProcessEngines

the jars activiti-engine-5.12.jar and a couple of bpmn jars are in the Maven Dependencies path.

This is probably a java beginner issue but what is wrong here?

[udoderk]

I am trying to get Activiti and Vaadin working together so I can "play" with the two with some simple code and learn.

The separate way would be a better way (imho), because a lot of things to be investigate and to study

I have added the following dependencies to Maven:
….
I am getting the following error:

java.lang.NoClassDefFoundError: org/activiti/engine/ProcessEngines

the jars activiti-engine-5.12.jar and a couple of bpmn jars are in the Maven Dependencies path.

This is probably a java beginner issue but what is wrong here?

you are not described, how to you started, that java code. But i assume, that no all needed libs are exist in runtime java class path. It may be, that your class was successfully compiled, but runtime java class path just differend from compile java class path. Check, if your web container has that libs.

BTW. In other topic you questioned about sources for Activiti Explorer. Keep just in mind, that Activiti Explorer uses the Vaadin of 6.8.x Releases. Your example uses the some API (com.vaadin.ui.UI) existed since Vaadin 7.0.x.

Vaadin 7 changes the basic architecture of Vaadin applications significantly, more than it did in th...

[ericsnyder]

Thanks udoderk:
What I finally did was create a Vaadin project with the wizard and a Activiti project with a wizard. I then set up the dependencies for Activiti in the Vaadin project using Ivy.

[udoderk]

Thanks udoderk:
What I finally did was create a Vaadin project with the wizard and a Activiti project with a wizard. I thin wet up the dependencies for Activiti in the Vaadin project using Ivy.

That is ok, but how to you start that web application? How to you deploy it to web container? Like written
https://vaadin.com/book/vaadin7/-/page/application.environment.html ? Do needed libraries exist under /WEB-IN/libs ???