优化代码：public List<ProjectCountVO> projectCount(String beginTime, String endTime, Integer forceType, String projectId) { ResultWrapper<QueryAllProjectName> resultWrapper = (ResultWrapper<QueryAllProjectName>) applicationServicePlatformClient.queryProjectName(projectId); if (resultWrapper.getData() == null) { return Collections.emptyList(); } String projectName = resultWrapper.getData().getProjectName(); List<TaskTask> taskTaskList = this.listStatisticsTask(beginTime, endTime, forceType, projectId); if (CollectionUtil.isEmpty(taskTaskList)) { return Collections.emptyList(); } List<ProjectCountVO> result = new ArrayList<>(); Map<String, List<TaskTask>> projectTaskMap = taskTaskList.stream().collect(Collectors.groupingBy(TaskTask::getProjectId)); for (Map.Entry<String, List<TaskTask>> projectTaskEntry : projectTaskMap.entrySet()) { projectId = projectTaskEntry.getKey(); ProjectCountVO projectCountVO = new ProjectCountVO(); projectCountVO.setId(projectId); projectCountVO.setName(projectName); List<TaskTask> taskList = projectTaskEntry.getValue(); projectCountVO.setTaskCount(taskList.size()); Integer problemCount = CollectionUtil.isEmpty(taskList) ? 0 : taskList.stream().collect(Collectors.summingInt(task -> Optional.ofNullable(task.getProblemNum()).orElse(0))); projectCountVO.setProblemCount(problemCount); result.add(projectCountVO); } return result; }

可以尝试以下优化：

1. 使用 Optional 类简化代码。可以使用 `Optional.ofNullable()` 来避免空指针异常，使用 `orElse()` 来指定默认值。

2. 使用 Stream API 来简化代码。可以使用 `Collectors.groupingBy()` 来对列表进行分组，使用 `Collectors.summingInt()` 来统计数量。

3. 减少方法调用次数。可以将 `resultWrapper.getData()` 的结果保存在变量中，避免多次调用。

4. 将变量名命名得更具有表现力。可以将 `taskTaskList` 改为 `tasks`，将 `projectTaskMap` 改为 `projectTasks`。

优化后的代码如下：

public List<ProjectCountVO> projectCount(String beginTime, String endTime, Integer forceType, String projectId) {
    ResultWrapper<QueryAllProjectName> resultWrapper = (ResultWrapper<QueryAllProjectName>) applicationServicePlatformClient.queryProjectName(projectId);
    QueryAllProjectName projectNameData = resultWrapper.getData();
    if (projectNameData == null) {
        return Collections.emptyList();
    }
    String projectName = projectNameData.getProjectName();

    List<TaskTask> tasks = this.listStatisticsTask(beginTime, endTime, forceType, projectId);
    if (CollectionUtil.isEmpty(tasks)) {
        return Collections.emptyList();
    }

    Map<String, List<TaskTask>> projectTasks = tasks.stream().collect(Collectors.groupingBy(TaskTask::getProjectId));

    List<ProjectCountVO> result = new ArrayList<>();
    for (Map.Entry<String, List<TaskTask>> projectTaskEntry : projectTasks.entrySet()) {
        String projectTaskId = projectTaskEntry.getKey();

        ProjectCountVO projectCountVO = new ProjectCountVO();
        projectCountVO.setId(projectTaskId);
        projectCountVO.setName(projectName);

        List<TaskTask> taskList = projectTaskEntry.getValue();
        projectCountVO.setTaskCount(taskList.size());

        Integer problemCount = taskList.stream()
                .map(TaskTask::getProblemNum)
                .filter(Objects::nonNull)
                .mapToInt(Integer::intValue)
                .sum();
        projectCountVO.setProblemCount(problemCount);

        result.add(projectCountVO);
    }

    return result;
}