newFixedThreadPool线程池实现多线程

复制代码

		List<PackageAgreementEntity> entityList = new CopyOnWriteArrayList<>();
        //多线程   10个线程
        //int threadNum = 10;
        int listSize = 300;
        List<List<PackageAgreementDto>> splitData = Lists.partition(packageAgreementList, listSize);
        //CountDownLatch latch = new CountDownLatch(splitData.size());
        //声明线程池对象
        ExecutorService touchWorker = Executors.newFixedThreadPool(splitData.size());
        //不加这个会导致线程不安全，丢失数据
        Semaphore semaphore = new Semaphore(splitData.size());//定义几个许可
        List<PackageAgreementErroDto> errorList2 = new CopyOnWriteArrayList();

        for (int i = 0; i < packageAgreementList.size(); i++) {
            final  int j = i;
            semaphore.acquire();
            touchWorker.execute(()->{
                try {
                        logger.info(Thread.currentThread().getName()+ j);
                        logger.info("数据第几条：" + j);
                        //校验物料、供应商、ou、地点信息是否存在
                        packageAgreementService.checkMultiData(packageAgreementList.get(j), j ,user, dateFormat,  errorList2, entityList);

                        semaphore.release();
                } catch (ParseException e) {
                    e.printStackTrace();
                }
            });
        }
        //每隔10s检测线程是否执行结束
        boolean flag = touchWorker.awaitTermination(10, TimeUnit.SECONDS);
         if(!flag){
            logger.info("一揽子协议价格录入完成！");
        }

需要注意的问题点，多线程处理List数据可能发生线程不安全，

引入CopyOnWriteArrayList，Semaphore解决，或者加锁解决问题；所有线程执行完毕后再进行后续业务的处理，引入awaitTermination()方法。