Java 中List集合使用多线程分段处理

因业务需要,需从excel读取数据并插入数据库,由于数据量较大,耗时较长,考虑使用多线程来处理

1.读取到的list按数据量分段

2.动态创建线程

public  class  ScmcommissionLineServiceImpl{




//导入数据
public  void importData(List  list){
            //500分一组
            int count = 500;
            int listSize = list.size();
            //线程数
            int RunSize = (listSize / count)+1;
 
            ThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(RunSize);
            CountDownLatch countDownLatch = new CountDownLatch(RunSize);
            List  newList = null ;
            for (int i = 0; i < RunSize; i++) {
                if((i+1)==RunSize){
                    int startIndex = (i*count);;
                    int endIndex = list.size();
                    newList =list.subList(startIndex,endIndex);
                }else{
                    int startIndex = i*count;;
                    int endIndex = (i+1)*count-1;
                    newList =list.subList(startIndex,endIndex);
                }
 
                ImportTask task= new ImportTask (newList,countDownLatch);
                executor.execute(task);
            }
 
            countDownLatch.await();  //主线程等待所有线程完成任务
            //所有线程完成任务后的一些业务
              System.out.println("插入数据完成!");
                   .....
             //关闭线程池
            executor.shutdown();
 
    }
   
 
    
 }
 
 
    class ImportTask implements Runnable{
        private List  list;
        private CountDownLatch countDownLatch;
        public ImportTask (List  list,CountDownLatch countDownLatch){
            this.list  = list ;
            this.countDownLatch=countDownLatch;
        }
 
        @Override
        public void run() {
            if(null!=list){
               //业务逻辑 
               
            }
            countDownLatch.countDown();//发出线程任务完成的信号

        }
    }