activiti会签情况下任意节点退回

/**
     * 
     * @param taskId 任务id
     * @param msg 批注
     * @param endActivityId 结束节点的activitiyId
     * @throws Exception
     */
    public void turnBackNew(String taskId, String msg, String endActivityId) throws Exception {
        Map variables;
        // 取得当前任务
        HistoricTaskInstance currTask = historyService
                .createHistoricTaskInstanceQuery().taskId(taskId)
                .singleResult();
        // 取得流程实例
        ProcessInstance instance = runtimeService
                .createProcessInstanceQuery()
                .processInstanceId(currTask.getProcessInstanceId())
                .singleResult();
        if (instance == null) {
            throw new RuntimeException("流程已结束");
        }
        variables = instance.getProcessVariables();
        // 取得流程定义
        ProcessDefinitionEntity definition = (ProcessDefinitionEntity) ((RepositoryServiceImpl) repositoryService)
                .getDeployedProcessDefinition(currTask
                        .getProcessDefinitionId());
        if (definition == null) {
            throw new RuntimeException("流程定义未找到");
        }
        // 取得上一步活动
        ActivityImpl currActivity = ((ProcessDefinitionImpl) definition)
                .findActivity(currTask.getTaskDefinitionKey());
        List rtnList = new ArrayList<>();
        List tempList = new ArrayList<>();
        List activities = iteratorBackActivity(
                taskId,
                currActivity,
                rtnList,
                tempList
        );
        if (activities == null || activities.size() <= 0) throw new RuntimeException("没有可以选择的驳回节点!");
        List list = taskService.createTaskQuery().processInstanceId(instance.getId()).list();
        for (Task task : list) {
            if (!task.getId().equals(taskId)) {
                task.setAssignee("排除标记");
                commitProcess(task.getId(), null, endActivityId);
            }
        }
        turnTransition(taskId, activities.get(0).getId(), null);
    }

    /**
     * @param taskId     当前任务ID
     * @param variables  流程变量
     * @param activityId 流程转向执行任务节点ID

     *                   此参数为空，默认为提交操作
     * @throws Exception
     */
    private void commitProcess(String taskId, Map variables,
                               String activityId) throws Exception {
        if (variables == null) {
            variables = new HashMap();
        }
        // 跳转节点为空，默认提交操作
        if (activityId == null || activityId.equals("")) {
            taskService.complete(taskId, variables);
        } else {// 流程转向操作
            turnTransition(taskId, activityId, variables);
        }
    }

    /**
     * 清空指定活动节点流向
     *
     * @param activityImpl 活动节点
     * @return 节点流向集合
     */
    private List clearTransition(ActivityImpl activityImpl) {
        // 存储当前节点所有流向临时变量
        List oriPvmTransitionList = new ArrayList();
        // 获取当前节点所有流向，存储到临时变量，然后清空
        List pvmTransitionList = activityImpl
                .getOutgoingTransitions();
        for (PvmTransition pvmTransition : pvmTransitionList) {
            oriPvmTransitionList.add(pvmTransition);
        }
        pvmTransitionList.clear();

        return oriPvmTransitionList;
    }

    /**
     * 还原指定活动节点流向
     *
     * @param activityImpl         活动节点
     * @param oriPvmTransitionList 原有节点流向集合
     */
    private void restoreTransition(ActivityImpl activityImpl,
                                   List oriPvmTransitionList) {
        // 清空现有流向
        List pvmTransitionList = activityImpl
                .getOutgoingTransitions();
        pvmTransitionList.clear();
        // 还原以前流向
        for (PvmTransition pvmTransition : oriPvmTransitionList) {
            pvmTransitionList.add(pvmTransition);
        }
    }

    /**
     * 流程转向操作
     *
     * @param taskId     当前任务ID
     * @param activityId 目标节点任务ID
     * @param variables  流程变量
     * @throws Exception
     */
    private void turnTransition(String taskId, String activityId,
                                Map variables) throws Exception {
        // 当前节点
        ActivityImpl currActivity = findActivitiImpl(taskId, null);
        // 清空当前流向
        List oriPvmTransitionList = clearTransition(currActivity);

        // 创建新流向
        TransitionImpl newTransition = currActivity.createOutgoingTransition();
        // 目标节点
        ActivityImpl pointActivity = findActivitiImpl(taskId, activityId);
        // 设置新流向的目标节点
        newTransition.setDestination(pointActivity);

        // 执行转向任务
        taskService.complete(taskId, variables);
        // 删除目标节点新流入
        pointActivity.getIncomingTransitions().remove(newTransition);

        // 还原以前流向
        restoreTransition(currActivity, oriPvmTransitionList);
    }

    /**
     * 迭代循环流程树结构，查询当前节点可驳回的任务节点
     *
     * @param taskId       当前任务ID
     * @param currActivity 当前活动节点
     * @param rtnList      存储回退节点集合
     * @param tempList     临时存储节点集合（存储一次迭代过程中的同级userTask节点）
     * @return 回退节点集合
     */
    private List iteratorBackActivity(String taskId,
                                                    ActivityImpl currActivity, List rtnList,
                                                    List tempList) throws Exception {
        // 查询流程定义，生成流程树结构
        ProcessInstance processInstance = findProcessInstanceByTaskId(taskId);

        // 当前节点的流入来源
        List incomingTransitions = currActivity
                .getIncomingTransitions();
        // 条件分支节点集合，userTask节点遍历完毕，迭代遍历此集合，查询条件分支对应的userTask节点
        List exclusiveGateways = new ArrayList();
        // 并行节点集合，userTask节点遍历完毕，迭代遍历此集合，查询并行节点对应的userTask节点
        List parallelGateways = new ArrayList();
        // 遍历当前节点所有流入路径
        for (PvmTransition pvmTransition : incomingTransitions) {
            TransitionImpl transitionImpl = (TransitionImpl) pvmTransition;
            ActivityImpl activityImpl = transitionImpl.getSource();
            String type = (String) activityImpl.getProperty("type");
            /**
             * 并行节点配置要求：

             * 必须成对出现，且要求分别配置节点ID为:XXX_start(开始)，XXX_end(结束)
             */
            if ("parallelGateway".equals(type)) {// 并行路线
                String gatewayId = activityImpl.getId();
                String gatewayType = gatewayId.substring(gatewayId
                        .lastIndexOf("_") + 1);
                if ("START".equals(gatewayType.toUpperCase())) {// 并行起点，停止递归
                    return rtnList;
                } else {// 并行终点，临时存储此节点，本次循环结束，迭代集合，查询对应的userTask节点
                    parallelGateways.add(activityImpl);
                }
            } else if ("startEvent".equals(type)) {// 开始节点，停止递归
                return rtnList;
            } else if ("userTask".equals(type)) {// 用户任务
                tempList.add(activityImpl);
            } else if ("exclusiveGateway".equals(type)) {// 分支路线，临时存储此节点，本次循环结束，迭代集合，查询对应的userTask节点
                currActivity = transitionImpl.getSource();
                exclusiveGateways.add(currActivity);
            }
        }

        /**
         * 迭代条件分支集合，查询对应的userTask节点
         */
        for (ActivityImpl activityImpl : exclusiveGateways) {
            iteratorBackActivity(taskId, activityImpl, rtnList, tempList);
        }

        /**
         * 迭代并行集合，查询对应的userTask节点
         */
        for (ActivityImpl activityImpl : parallelGateways) {
            iteratorBackActivity(taskId, activityImpl, rtnList, tempList);
        }

        /**
         * 根据同级userTask集合，过滤最近发生的节点
         */
        currActivity = filterNewestActivity(processInstance, tempList);
        if (currActivity != null) {
            // 查询当前节点的流向是否为并行终点，并获取并行起点ID
            String id = findParallelGatewayId(currActivity);
            if (id == null || id.equals("")) {// 并行起点ID为空，此节点流向不是并行终点，符合驳回条件，存储此节点
                rtnList.add(currActivity);
            } else {// 根据并行起点ID查询当前节点，然后迭代查询其对应的userTask任务节点
                currActivity = findActivitiImpl(taskId, id);
            }

            // 清空本次迭代临时集合
            tempList.clear();
            // 执行下次迭代
            iteratorBackActivity(taskId, currActivity, rtnList, tempList);
        }
        return rtnList;
    }

    /**
     * 根据当前节点，查询输出流向是否为并行终点，如果为并行终点，则拼装对应的并行起点ID
     *
     * @param activityImpl 当前节点
     * @return
     */
    private String findParallelGatewayId(ActivityImpl activityImpl) {
        List incomingTransitions = activityImpl
                .getOutgoingTransitions();
        for (PvmTransition pvmTransition : incomingTransitions) {
            TransitionImpl transitionImpl = (TransitionImpl) pvmTransition;
            activityImpl = transitionImpl.getDestination();
            String type = (String) activityImpl.getProperty("type");
            if ("parallelGateway".equals(type)) {// 并行路线
                String gatewayId = activityImpl.getId();
                String gatewayType = gatewayId.substring(gatewayId
                        .lastIndexOf("_") + 1);
                if ("END".equals(gatewayType.toUpperCase())) {
                    return gatewayId.substring(0, gatewayId.lastIndexOf("_"))
                            + "_start";
                }
            }
        }
        return null;
    }

    /**
     * 根据流入任务集合，查询最近一次的流入任务节点
     *
     * @param processInstance 流程实例
     * @param tempList        流入任务集合
     * @return
     */
    private ActivityImpl filterNewestActivity(ProcessInstance processInstance,
                                              List tempList) {
        while (tempList.size() > 0) {
            ActivityImpl activity_1 = tempList.get(0);
            HistoricActivityInstance activityInstance_1 = findHistoricUserTask(
                    processInstance, activity_1.getId());
            if (activityInstance_1 == null) {
                tempList.remove(activity_1);
                continue;
            }

            if (tempList.size() > 1) {
                ActivityImpl activity_2 = tempList.get(1);
                HistoricActivityInstance activityInstance_2 = findHistoricUserTask(
                        processInstance, activity_2.getId());
                if (activityInstance_2 == null) {
                    tempList.remove(activity_2);
                    continue;
                }

                if (activityInstance_1.getEndTime().before(
                        activityInstance_2.getEndTime())) {
                    tempList.remove(activity_1);
                } else {
                    tempList.remove(activity_2);
                }
            } else {
                break;
            }
        }
        if (tempList.size() > 0) {
            return tempList.get(0);
        }
        return null;
    }

    /**
     * 查询指定任务节点的最新记录
     *
     * @param processInstance 流程实例
     * @param activityId
     * @return
     */
    private HistoricActivityInstance findHistoricUserTask(
            ProcessInstance processInstance, String activityId) {
        HistoricActivityInstance rtnVal = null;
        // 查询当前流程实例审批结束的历史节点
        List historicActivityInstances = historyService
                .createHistoricActivityInstanceQuery().activityType("userTask")
                .processInstanceId(processInstance.getId()).activityId(
                        activityId).finished()
                .orderByHistoricActivityInstanceEndTime().desc().list();
        if (historicActivityInstances.size() > 0) {
            rtnVal = historicActivityInstances.get(0);
        }

        return rtnVal;
    }

    /**
     * 根据任务ID和节点ID获取活动节点 

     *
     * @param taskId     任务ID
     * @param activityId 活动节点ID 

     *                   如果为null或""，则默认查询当前活动节点 

     *                   如果为"end"，则查询结束节点 

     * @return
     * @throws Exception
     */
    private ActivityImpl findActivitiImpl(String taskId, String activityId)
            throws Exception {
        // 取得流程定义
        ProcessDefinitionEntity processDefinition = findProcessDefinitionEntityByTaskId(taskId);

        // 获取当前活动节点ID
        if (activityId == null || "".equals(activityId)) {
            activityId = findTaskById(taskId).getTaskDefinitionKey();
        }

        // 根据流程定义，获取该流程实例的结束节点
        if (activityId.toUpperCase().equals("END")) {
            for (ActivityImpl activityImpl : processDefinition.getActivities()) {
                List pvmTransitionList = activityImpl
                        .getOutgoingTransitions();
                if (pvmTransitionList.isEmpty()) {
                    return activityImpl;
                }
            }
        }

        // 根据节点ID，获取对应的活动节点
        ActivityImpl activityImpl = ((ProcessDefinitionImpl) processDefinition)
                .findActivity(activityId);

        return activityImpl;
    }

    /**
     * 根据任务ID获取流程定义
     *
     * @param taskId 任务ID
     * @return
     * @throws Exception
     */
    private ProcessDefinitionEntity findProcessDefinitionEntityByTaskId(
            String taskId) throws Exception {
        // 取得流程定义
        ProcessDefinitionEntity processDefinition = (ProcessDefinitionEntity) ((RepositoryServiceImpl) repositoryService)
                .getDeployedProcessDefinition(findTaskById(taskId)
                        .getProcessDefinitionId());

        if (processDefinition == null) {
            throw new Exception("流程定义未找到!");
        }

        return processDefinition;
    }

    /**
     * 根据任务ID获得任务实例
     *
     * @param taskId 任务ID
     * @return
     * @throws Exception
     */
    private TaskEntity findTaskById(String taskId) throws Exception {
        TaskEntity task = (TaskEntity) taskService.createTaskQuery().taskId(
                taskId).singleResult();
        if (task == null) {
            throw new Exception("任务实例未找到!");
        }
        return task;
    }

    /**
     * 根据任务ID获取对应的流程实例
     *
     * @param taskId 任务ID
     * @return
     * @throws Exception
     */
    private ProcessInstance findProcessInstanceByTaskId(String taskId)
            throws Exception {
        // 找到流程实例
        ProcessInstance processInstance = runtimeService
                .createProcessInstanceQuery().processInstanceId(
                        findTaskById(taskId).getProcessInstanceId())
                .singleResult();
        if (processInstance == null) {
            throw new Exception("流程实例未找到!");
        }
        return processInstance;
    }