状态模式

状态模式最常用就是多种状态之间的管理

这种较为复杂的逻辑如果采用if else 来判断很容易写错逻辑，新增和修改逻辑也很麻烦

‍ 给每一个状态定义不同状态转换的处理方法，

@Component
public class ArraignmentState extends AbstractState {

    @Override
    public Result arraignment(Long activityId, Enum<Constants.ActivityState> currentState) {
        return Result.buildResult(Constants.ResponseCode.UN_ERROR, "待审核状态不可重复提审");
    }

    @Override
    public Result checkPass(Long activityId, Enum<Constants.ActivityState> currentState) {
        boolean isSuccess = activityRepository.alterStatus(activityId, currentState, Constants.ActivityState.PASS);
        return isSuccess ? Result.buildResult(Constants.ResponseCode.SUCCESS, "活动审核通过完成") : Result.buildErrorResult("活动状态变更失败");
    }

    @Override
    public Result checkRefuse(Long activityId, Enum<Constants.ActivityState> currentState) {
        boolean isSuccess = activityRepository.alterStatus(activityId, currentState, Constants.ActivityState.REFUSE);
        return isSuccess ? Result.buildResult(Constants.ResponseCode.SUCCESS, "活动审核拒绝完成") : Result.buildErrorResult("活动状态变更失败");
    }
	//  ......
   
}

把处理bean放入map中

public class StateConfig {

    @Resource
    private ArraignmentState arraignmentState;
    @Resource
    private CloseState closeState;
    @Resource
    private DoingState doingState;
    @Resource
    private EditingState editingState;
    @Resource
    private OpenState openState;
    @Resource
    private PassState passState;
    @Resource
    private RefuseState refuseState;

    protected Map<Enum<Constants.ActivityState>, AbstractState> stateGroup = new ConcurrentHashMap<>();

    @PostConstruct
    public void init() {
        stateGroup.put(Constants.ActivityState.ARRAIGNMENT, arraignmentState);
        stateGroup.put(Constants.ActivityState.CLOSE, closeState);
        stateGroup.put(Constants.ActivityState.DOING, doingState);
        stateGroup.put(Constants.ActivityState.EDIT, editingState);
        stateGroup.put(Constants.ActivityState.OPEN, openState);
        stateGroup.put(Constants.ActivityState.PASS, passState);
        stateGroup.put(Constants.ActivityState.REFUSE, refuseState);
    }

}

根据传入的参数类型，调用相应的状态处理方法

@Service
public class StateHandlerImpl extends StateConfig implements IStateHandler {

    @Override
    public Result arraignment(Long activityId, Enum<Constants.ActivityState> currentStatus) {
        return stateGroup.get(currentStatus).arraignment(activityId, currentStatus);
    }

    @Override
    public Result checkPass(Long activityId, Enum<Constants.ActivityState> currentStatus) {
        return stateGroup.get(currentStatus).checkPass(activityId, currentStatus);
    }

    @Override
    public Result checkRefuse(Long activityId, Enum<Constants.ActivityState> currentStatus) {
        return stateGroup.get(currentStatus).checkRefuse(activityId, currentStatus);
    }

    @Override
    public Result checkRevoke(Long activityId, Enum<Constants.ActivityState> currentStatus) {
        return stateGroup.get(currentStatus).checkRevoke(activityId, currentStatus);
    }

    @Override
    public Result close(Long activityId, Enum<Constants.ActivityState> currentStatus) {
        return stateGroup.get(currentStatus).close(activityId, currentStatus);
    }

    @Override
    public Result open(Long activityId, Enum<Constants.ActivityState> currentStatus) {
        return stateGroup.get(currentStatus).open(activityId, currentStatus);
    }

    @Override
    public Result doing(Long activityId, Enum<Constants.ActivityState> currentStatus) {
        return stateGroup.get(currentStatus).doing(activityId, currentStatus);
    }

}

使用时，传入操作（用户id，当前状态）即可进行处理

stateHandler.arraignment(100001L, Constants.ActivityState.EDIT));

设计模式之状态模式

状态模式