Thank you!
I solve the problem in this way:
//get session
StatefulKnowledgeSession sess = this.jbpm5helper.buildJbpmSession(0);
//get processInstance by processInstanceId
RuleFlowProcessInstance processInstance=(RuleFlowProcessInstance)sess.getProcessInstance(processInstanceId);
//get the id of node To be executed
List<NodeInstance> nodeList=(List<NodeInstance>)processInstance.getNodeInstances();
int currentNodeId=(int)nodeList.get(0).getNodeId();