activity节点任意跳转（包含单实例、多实例）

实现思路：
处理掉当前的代办节点（也就是删除正在运行的该任务，更新维护历史数据）
跳转到目标节点，并把目标节点作为待办任务节点

处理掉当前的代办节点（也就是删除正在运行的该任务，更新维护历史数据）
跳转到目标节点，并把目标节点作为待办任务节点

要继续运转流程，则向operations中压入ContinueProcessOperation，
多实例压入planContinueMultiInstanceOperation
要结束流程则压入EndExecutionOperation。
在每一个操作完成的时候，将接下来要执行的操作压入operations栈中，这样就达到了流程运转的效果

代码如下（示例）：

public class JumpTaskCmd implements Command, Serializable {
   
    private List taskIds;

    
    private String targetNodeId;
    private Map vars;

    public JumpMultiCmd(List taskIds, String targetNodeId, Map vars) {
        this.taskIds = taskIds;
        this.targetNodeId = targetNodeId;
        this.vars = vars;
    }

    @Override
    public Void execute(CommandContext commandContext) {
        //获取其中一个代办任务
        String taskId = taskIds.get(0);
        //任务执行管理器
        TaskEntityManager taskEntityManager = commandContext.getTaskEntityManager();
        ExecutionEntityManager executionEntityManager = commandContext.getExecutionEntityManager();
        TaskEntity taskEntity = taskEntityManager.findById(taskId);
        //流程定义对象信息
        String processDefinitionId = taskEntity.getProcessDefinitionId();
        Process process = ProcessDefinitionUtil.getProcess(processDefinitionId);
        //节点的元信息对象，封装了节点的元数据，如入线和出线
        Activity flowElement = (Activity) process.getFlowElement(taskEntity.getTaskDefinitionKey());

        // 执行实例对象
        String executionId = taskEntity.getExecutionId();
        ExecutionEntity currentExecutionEntity = executionEntityManager.findById(executionId);

        Object behavior = flowElement.getBehavior();
        //判断当前节点的行为类，即是否多实例任务类型，主要做两件事，删除2级实例下的三级实例，然后重新设置2级实例的信息执行更新操作
        if (behavior instanceof MultiInstanceActivityBehavior) {
            HistoricTaskInstanceEntityManager historicTaskInstance = commandContext.getHistoricTaskInstanceEntityManager();
            this.taskIds.forEach(historicTaskInstance::delete);

            executionEntityManager.deleteChildExecutions(currentExecutionEntity, "jump task", false);
            currentExecutionEntity.setActive(true);
            currentExecutionEntity.setMultiInstanceRoot(false);
            executionEntityManager.update(currentExecutionEntity);
        } else {
            //不是多实例
            //删除历史任务节点
            HistoricTaskInstanceEntityManager historicTaskInstance = commandContext.getHistoricTaskInstanceEntityManager();
            historicTaskInstance.delete(taskId);
            //删除当前的任务并把条件删掉
            IdentityLinkEntityManager identityLinkEntityManager = commandContext.getIdentityLinkEntityManager();
            identityLinkEntityManager.deleteIdentityLinksByTaskId(taskId);
            //taskEntityManager.delete(taskId); 报外键冲突，执行前面的代码
            taskEntityManager.deleteTask(taskEntity, "jumpReason", false, false);
        }
        //使用agenda驱动实例的继续运转，即跳入到目标节点
        ActivitiEngineAgenda agenda = commandContext.getAgenda();

        // 如果目标节点为结束节点（不是用户节点）
        if (FLOW_NODE_EVENT_END.equals(targetNodeId)) {
            FlowElement targetFlowElement = process.getFlowElement(targetNodeId);
            
            currentExecutionEntity.setCurrentFlowElement(targetFlowElement);
            agenda.planEndExecutionOperation(currentExecutionEntity);
            return null;
        }

        // 目标节点处理
        Activity targetFlowElement = (Activity) process.getFlowElement(targetNodeId);
        behavior = targetFlowElement.getBehavior();

        // 当目标节点为多实例节点时，需要从执行实例中获取它们父实例对象
        if (behavior instanceof MultiInstanceActivityBehavior) {
            //待跳出节点的二级实例对象(多实例下的执行实例对象为三级实例对象)
            ExecutionEntity secondExecutionEntity = currentExecutionEntity.getParent();
            secondExecutionEntity.setCurrentFlowElement(targetFlowElement);
            if (!Objects.isNull(vars) && vars.size() > 0) {// 如需要提供的参数
                secondExecutionEntity.setVariables(vars);
            }
            agenda.planContinueMultiInstanceOperation(secondExecutionEntity);
            return null;
        }

        if (!Objects.isNull(vars) && vars.size() > 0) {
            currentExecutionEntity.setVariables(vars);
        }
        currentExecutionEntity.setCurrentFlowElement(targetFlowElement);
        agenda.planContinueProcessInCompensation(currentExecutionEntity);

        return null;
    }
 }

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Java工作流管理系统(activity6.0)