Activiti bug(?) with Extension Attributes

CustomAttributeBug.java

package activiti;


import java.io.UnsupportedEncodingException;
import java.util.concurrent.atomic.AtomicInteger;

import org.activiti.bpmn.converter.BpmnXMLConverter;
import org.activiti.bpmn.model.Activity;
import org.activiti.bpmn.model.BoundaryEvent;
import org.activiti.bpmn.model.BpmnModel;
import org.activiti.bpmn.model.EndEvent;
import org.activiti.bpmn.model.ExtensionAttribute;
import org.activiti.bpmn.model.FlowElement;
import org.activiti.bpmn.model.Process;
import org.activiti.bpmn.model.SequenceFlow;
import org.activiti.bpmn.model.StartEvent;
import org.activiti.bpmn.model.TerminateEventDefinition;
import org.activiti.bpmn.model.TimerEventDefinition;
import org.activiti.bpmn.model.UserTask;

public class CustomAttributeBug {

	private static final String NAMESPACE = "http://www.acme.com/bpmn";
	private static final String PFX = "pfx";

	public static void main(String[] args) throws UnsupportedEncodingException {
		
		CustomAttributeBug bug = new CustomAttributeBug();
		bug.generate();
		
		BpmnXMLConverter conv = new BpmnXMLConverter();
		byte[] bstr = conv.convertToXML(bug.model);

		System.out.println(new String(bstr, "UTF-8"));
	}

	private Process process;
	private BpmnModel model;
	private AtomicInteger idx;
	
	public CustomAttributeBug() {
		process = new Process();
		process.setId("TEST");
		model = new BpmnModel();
		model.addNamespace(PFX, NAMESPACE);
		model.addProcess(process);
		idx = new AtomicInteger();
	}

	public void generate() {
		
		String start = startEvent();
		String task1 = userTask("Task 1", "TestValue");
		flow(start, task1, null);
		
		String task2 = userTask("Task with Timeout", null);
		String timer = timerBoundary("PT10M", task2, "CustomValue");
		flow(task1, task2, null);
		String end1 = endEvent(false);
		flow(task2, end1, null);
		
		String task3 = userTask("Task on Timeout", "FooBar");
		flow(timer, task3, null);
		String end2 = endEvent(false);
		flow(task3, end2, null);
	}

	public void flow(String source, String target, String condition) {
		SequenceFlow flow = new SequenceFlow();
		String fid = "flow" + idx.incrementAndGet();
		flow.setId(fid);
		flow.setSourceRef(source);
		flow.setTargetRef(target);
		if(condition != null) {
			flow.setConditionExpression(condition);
		}
		process.addFlowElement(flow);
	}

	public String startEvent() {
		StartEvent start = new StartEvent();
		String id = "startevent" + idx.incrementAndGet();
		start.setId(id);
		start.setName("Start Event");
		process.addFlowElement(start);
		return id;
	}

	public String userTask(String name, String attribute) {
		UserTask task = new UserTask();
		String id = "usertask" + idx.incrementAndGet();
		task.setId(id);
		task.setName(name);
		if(attribute != null) {
			setAttribute(task, attribute);
		}
		process.addFlowElement(task);
		return id;
	}

	public String endEvent(boolean terminate) {
		EndEvent event = new EndEvent();
		String id = "endevent" + idx.incrementAndGet();
		event.setId(id);
		if(terminate) {
			event.addEventDefinition(new TerminateEventDefinition());
		}
		process.addFlowElement(event);
		return id;
	}

	public String timerBoundary(String expression, String attached, String customAttribute) {
		String id = "boundaryevent" + idx.incrementAndGet();
		BoundaryEvent be = new BoundaryEvent();
		be.setId(id);
		be.setName("Timer");
		be.setAttachedToRef((Activity) process.getFlowElement(attached));
		be.setCancelActivity(false);
		TimerEventDefinition event = new TimerEventDefinition();
		event.setTimeDate(expression);
		be.addEventDefinition(event);
		process.addFlowElement(be);
		setAttribute(be, customAttribute);
		return id;
	}

	public void setAttribute(FlowElement element, String value) {
		ExtensionAttribute attr = new ExtensionAttribute("customAttribute");
		attr.setNamespace(NAMESPACE);
		attr.setValue(value);
		element.addAttribute(attr);
	}

}

output.bpmn

<?xml version='1.0' encoding='UTF-8'?>
<definitions xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:activiti="http://activiti.org/bpmn" 
    xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI" xmlns:omgdc="http://www.omg.org/spec/DD/20100524/DC" 
    xmlns:omgdi="http://www.omg.org/spec/DD/20100524/DI" xmlns:pfx="http://www.acme.com/bpmn" 
    typeLanguage="http://www.w3.org/2001/XMLSchema" expressionLanguage="http://www.w3.org/1999/XPath" 
    targetNamespace="http://www.activiti.org/test">
  <process id="TEST" isExecutable="true">
    <startEvent id="startevent1" name="Start Event"/>
    <userTask id="usertask2" name="Task 1" pfx:customAttribute="TestValue"/>
    <sequenceFlow id="flow3" sourceRef="startevent1" targetRef="usertask2"/>
    <userTask id="usertask4" name="Task with Timeout"/>
    <boundaryEvent id="boundaryevent5" name="Timer" attachedToRef="usertask4" cancelActivity="false">
      <timerEventDefinition>
        <timeDate>PT10M</timeDate>
      </timerEventDefinition>
    </boundaryEvent>
    <sequenceFlow id="flow6" sourceRef="usertask2" targetRef="usertask4"/>
    <endEvent id="endevent7"/>
    <sequenceFlow id="flow8" sourceRef="usertask4" targetRef="endevent7"/>
    <userTask id="usertask9" name="Task on Timeout" pfx:customAttribute="FooBar"/>
    <sequenceFlow id="flow10" sourceRef="boundaryevent5" targetRef="usertask9"/>
    <endEvent id="endevent11"/>
    <sequenceFlow id="flow12" sourceRef="usertask9" targetRef="endevent11"/>
  </process>
  <bpmndi:BPMNDiagram id="BPMNDiagram_TEST">
    <bpmndi:BPMNPlane bpmnElement="TEST" id="BPMNPlane_TEST"/>
  </bpmndi:BPMNDiagram>
</definitions>

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