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dataInputAssociation <assignment> expressions
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created by <a href="https://community.jboss.org/people/marnold">M Arnold</a> in <i>jBPM</i> - <a href="https://community.jboss.org/message/647913#647913">View the full discussion</a>
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<div class="jive-rendered-content"><p>Hi,</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>I'm struggling to map input parameters to my task from process variables.  I can't find much documentation besides <a class="jive-link-external-small" href="http://docs.jboss.org/jbpm/v5.2/userguide/ch05.html#sec.data">5.8.1. Data</a>, and the BPMN2 spec from OMG is cryptic.</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>I have a task something like this:</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p><code><p>        <task id="_4" tns:taskName="Custom" name="sendCustom"></p><p>            <incoming>_2-_4</incoming></p><p>            <outgoing>_4-_5</outgoing></p><p>            <ioSpecification id="InputOutputSpecification_1"></p><p>                <dataInput id="_4_messageInInput" name="messageIn" /></p><p>                <dataOutput id="_4_messageOutOutput" name="messageOut" /></p><p>                <inputSet id="InputSet_1"></p><p>                    <dataInputRefs>_4_messageInInput</dataInputRefs></p><p>                </inputSet></p><p>                <outputSet id="OutputSet_1"></p><p>                    <dataOutputRefs>_4_messageOutOutput</dataOutputRefs></p><p>                </outputSet></p><p>            </ioSpecification></p><p>            <dataInputAssociation id="DataInputAssociation_2"></p><p>                <sourceRef>event</sourceRef></p><p>                <targetRef>_4_messageInInput</targetRef></p><p>                <assignment id="Assignment_2"></p><p>                    <from xsi:type="tFormalExpression" id="FormalExpression_3">.</from></p><p>                    <to xsi:type="tFormalExpression" id="FormalExpression_4">.</to></p><p>                </assignment></p><p>            </dataInputAssociation></p><p>            <dataOutputAssociation id="DataOutputAssociation_1"></p><p>                <sourceRef>_4_messageOutOutput</sourceRef></p><p>                <targetRef>resultMessage_4</targetRef></p><p>            </dataOutputAssociation></p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>        </task></p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p></code></p><p>Where 'event' is a process variable.  So what can I put in the <assignment><to> and <from>?  An XPath expression?  What if it's not XML?  When I can I use #{event}?  What are the valid values for from@xsi:type besides "tFormalExpression"?</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>When I execute this task as it is above, I get:</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p><code><p>Caused by: java.lang.NullPointerException</p><p>        at org.jbpm.bpmn2.xpath.XPATHAssignmentAction.execute(XPATHAssignmentAction.java:91)</p><p>        at org.jbpm.workflow.instance.node.WorkItemNodeInstance.handleAssignment(WorkItemNodeInstance.java:193)</p><p>        ... 81 more</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p></code></p><p>I'm sorry if this is a very basic or broad question.  I've scoured the web and really can't find many examples.</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>Thanks in advance for help.</p></div>
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<p style="margin: 0;">Reply to this message by <a href="https://community.jboss.org/message/647913#647913">going to Community</a></p>
<p style="margin: 0;">Start a new discussion in jBPM at <a href="https://community.jboss.org/choose-container!input.jspa?contentType=1&containerType=14&container=2034">Community</a></p>
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