JavaPairRDD<String, Integer> ones = words.map(new PairFunction<String, String, Integer>() { @Override public Tuple2<String, Integer> call(String s) { return new Tuple2<String, Integer>(s, 1); } }); 优化

这段代码可以进行一些优化，如下：

1. 使用Lambda表达式代替匿名内部类，简化代码：

JavaPairRDD<String, Integer> ones = words.map(s -> new Tuple2<>(s, 1));

2. 如果使用Java 8及以上版本，可以使用Stream API进行统计，代码更加简洁：

Map<String, Long> wordCounts = words.collect(Collectors.groupingBy(Function.identity(), Collectors.counting()));

这里还有一个小优化：如果你只需要统计单词数量，可以使用flatMap和reduceByKey代替map和reduce，如下：

JavaPairRDD<String, Integer> wordCounts = words.flatMap(s -> Arrays.asList(s.split(" ")).iterator())
        .mapToPair(word -> new Tuple2<>(word, 1))
        .reduceByKey((a, b) -> a + b);

这样可以避免在map操作时创建不必要的Tuple2对象，提高性能。

相关问题

修改下面代码：@Override public List<ProjectCountVO> projectCount(String beginTime, String endTime, Integer forceType, String projectId) { 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); //查询项目名称 projectName = applicationServicePlatformClientProxy.get String projectName = Optional.ofNullable(projectTaskMap.get(projectId)).map(taskList -> taskList.get(0).getName()).orElse(""); 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; }

@Override
public List<ProjectCountVO> projectCount(String beginTime, String endTime, Integer forceType, String projectId) {
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);
//查询项目名称
String projectName = Optional.ofNullable(projectTaskMap.get(projectId)).map(taskList -> taskList.get(0).getProjectName()).orElse("");
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;
}

检查并修改下面代码：@Override public List<ProjectCountVO> projectCount(String beginTime, String endTime, Integer forceType, String projectId) { 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); //查询项目名称 String projectName = Optional.ofNullable(applicationServicePlatformClientProxy.queryProjectName(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; }

@Override
public List<ProjectCountVO> projectCount(String beginTime, String endTime, Integer forceType, String projectId) {
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);
//查询项目名称
String projectName = Optional.ofNullable(applicationServicePlatformClientProxy.queryProjectName(projectId)).orElse("");
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;
}

修改说明：

1. 在查询项目名称时，应该在 Optional.ofNullable() 后面加上 orElse("")，以避免 projectName 为空时出现 NullPointerException。
2. 对于 Optional.ofNullable(task.getProblemNum()).orElse(0) 这一行代码，建议加上括号以提高可读性。