List erniesTasks = taskMgmtSession.findTaskInstances("ernie");
TaskInstance evaluateTaskInstance = (TaskInstance) erniesTasks.get(0);
// this variable is set in the task instance variables, but
// should not be submitted to the process context variables.
evaluateTaskInstance.setVariable("item", "this is not allowed");
evaluateTaskInstance.end();
newTransaction();
processInstance = graphSession.loadProcessInstance(processInstanceId);
contextInstance = processInstance.getContextInstance();