常见NPE

原创于 2025-09-13 16:58:53 发布 · 114 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#java #spring boot

重学 java 后端专栏收录该内容

9 篇文章

订阅专栏

场景一 LinkedBlockingQueue 的 offer 和poll

@Component
public class AlarmReviewDataQueue {

    private final LinkedBlockingQueue<AlgorithmAlarmReviewRecordDTO> queue = new LinkedBlockingQueue<>(5000);

    public void offer(AlgorithmAlarmReviewRecordDTO record) {
        queue.offer(record);
    }

    public AlgorithmAlarmReviewRecordDTO poll() {
        return queue.poll();
    }


}

Caused by: java.lang.NullPointerException: null
	at com.qif.icms.ai.service.impl.AlarmReviewDataComsumerService.consume(AlarmReviewDataComsumerService.java:60)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	
	
AlgorithmAlarmReviewRecordDTO algorithmAlarmReviewRecordDTO = alarmReviewDataQueue.poll();
List<PointInfo> pointInfo = algorithmAlarmReviewRecordDTO.getPointInfo();

有NPE的风险
//这个地方就要 判断 algorithmAlarmReviewRecordDTO  不为null