SpringBoot-线程池ThreadPoolExecutor异步处理（包含拆分集合工具类）-编程知识

ThreadPoolExecutor VS ThreadPoolTaskExecutor

ThreadPoolTaskExecutor是对ThreadPoolExecutor进行了封装处理。

在这里插入图片描述

配置文件application.yml

# 异步线程配置 自定义使用参数
async:executor:thread:core_pool_size: 10max_pool_size:  100   # 配置最大线程数queue_capacity:  99988  # 配置队列大小keep_alive_seconds:  20  #设置线程空闲等待时间秒sname:prefix: async-thread-  # 配置线程池中的线程的名称前缀

配置类

@Configuration
@EnableAsync
@Slf4j
public class ThreadPoolConfig{//自定义使用参数@Value("${async.executor.thread.core_pool_size}")private int corePoolSize;   //配置核心线程数@Value("${async.executor.thread.max_pool_size}")private int maxPoolSize;    //配置最大线程数@Value("${async.executor.thread.queue_capacity}")private int queueCapacity;@Value("${async.executor.thread.name.prefix}")private String namePrefix;@Value("${async.executor.thread.keep_alive_seconds}")private int keepAliveSeconds;/**1.自定义asyncServieExecutor线程池*/@Bean(name = "asyncServiceExecutor")public ThreadPoolTaskExecutor asyncServiceExecutor(){log.info("start asyncServiceExecutor......");ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();//配置核心线程数executor.setCorePoolSize(corePoolSize);//配置最大线程数executor.setMaxPoolSize(maxPoolSize);//设置线程空闲等待时间 sexecutor.setKeepAliveSeconds(keepAliveSeconds);//配置队列大小 设置任务等待队列的大小executor.setQueueCapacity(queueCapacity);//配置线程池中的线程的名称前缀//设置线程池内线程名称的前缀-------阿里编码规约推荐--方便出错后进行调试executor.setThreadNamePrefix(namePrefix);/**rejection-policy：当pool已经达到max size的时候，如何处理新任务CALLER_RUNS：不在新线程中执行任务，而是有调用者所在的线程来执行*/executor.setRejectedExecutionHandler(new ThreadPoolExecutor.DiscardPolicy());//执行初始化executor.initialize();return executor;}/**公共线程池，利用系统availableProcessors线程数量进行计算*/@Bean(name="commonThreadPoolTaskExecutor")public ThreadPoolTaskExecutor commonThreadPoolTaskExecutor(){ThreadPoolTaskExecutor pool = new ThreadPoolTaskExecutor();// 返回可用处理器的Java虚拟机的数量int processNum = Runtime.getRuntime().availableProcessors();int corePoolSize = (int)(processNum / (1-0.2));int maxPoolSize = (int)(processNum / (1-0.5));pool.setCorePoolSize(corePoolSize); // 核心池大小pool.setMaxPoolSize(maxPoolSize); // 最大线程数pool.setQueueCapacity(maxPoolSize * 1000); // 队列程度pool.setThreadPriority(Thread.MAX_PRIORITY);pool.setDaemon(false);pool.setKeepAliveSeconds(300);// 线程空闲时间		return pool;}/**自定义defaultThreadPoolExecutor线程池*/@Bean(name="defaultThreadPoolExecutor",destroyMethod = "shutdown")public ThreadPoolExecutor systemCheckPoolExecutorService(){int maxNumPool=Runtime.getRuntime().availableProcessors();return new ThreadPoolExecutor(3,maxNumPool,60,TimeUnit.SECONDS,new LinkedBlockingQueue<Runnable>(10000),//置线程名前缀，例如设置前缀为hutool-thread-，则线程名为hutool-thread-1之类。new ThreadFactoryBuilder().setNamePrefix("default-executor-thread-%d").build(),(r, executor) -> log.error("system pool is full! "));}
}

异步线程业务类

//自定义asyncServiceExecutor线程池
@Override
@Async("asyncServiceExecutor")
public void executeAsync(List<Student> students,StudentService studentService,CountDownLatch countDownLatch){try{log.info("start executeAsync");//异步线程要做的事情studentService.saveBatch(students);log.info("end executeAsync");}finally{countDownLatch.countDown();// 很关键, 无论上面程序是否异常必须执行countDown,否则await无法释放}
}

拆分集合工具类

public class SplitListUtils {/*** 功能描述:拆分集合* @param <T> 泛型对象* @MethodName: split* @MethodParam: [resList:需要拆分的集合, subListLength:每个子集合的元素个数]* @Return: java.util.List<java.util.List<T>>:返回拆分后的各个集合组成的列表* 代码里面用到了guava和common的结合工具类* @Author: yyalin* @CreateDate: 2022/5/6 14:44*/public static <T> List<List<T>> split(List<T> resList, int subListLength) {if (CollectionUtils.isEmpty(resList) || subListLength <= 0) {return Lists.newArrayList();}List<List<T>> ret = Lists.newArrayList();int size = resList.size();if (size <= subListLength) {// 数据量不足 subListLength 指定的大小ret.add(resList);} else {int pre = size / subListLength;int last = size % subListLength;// 前面pre个集合，每个大小都是 subListLength 个元素for (int i = 0; i < pre; i++) {List<T> itemList = Lists.newArrayList();for (int j = 0; j < subListLength; j++) {itemList.add(resList.get(i * subListLength + j));}ret.add(itemList);}// last的进行处理if (last > 0) {List<T> itemList = Lists.newArrayList();for (int i = 0; i < last; i++) {itemList.add(resList.get(pre * subListLength + i));}ret.add(itemList);}}return ret;}/*** 功能描述:方法二：集合切割类，就是把一个大集合切割成多个指定条数的小集合，方便往数据库插入数据* 推荐使用* @MethodName: pagingList* @MethodParam:[resList:需要拆分的集合, subListLength:每个子集合的元素个数]* @Return: java.util.List<java.util.List<T>>：返回拆分后的各个集合组成的列表* @Author: yyalin* @CreateDate: 2022/5/6 15:15*/public static <T> List<List<T>> pagingList(List<T> resList, int pageSize){//判断是否为空if (CollectionUtils.isEmpty(resList) || pageSize <= 0) {return Lists.newArrayList();}int length = resList.size();int num = (length+pageSize-1)/pageSize;List<List<T>> newList =  new ArrayList<>();for(int i=0;i<num;i++){int fromIndex = i*pageSize;int toIndex = (i+1)*pageSize<length?(i+1)*pageSize:length;newList.add(resList.subList(fromIndex,toIndex));}return newList;}// 运行测试代码 可以按顺序拆分为11个集合public static void main(String[] args) {//初始化数据List<String> list = Lists.newArrayList();int size = 19;for (int i = 0; i < size; i++) {list.add("hello-" + i);}// 大集合里面包含多个小集合List<List<String>> temps = pagingList(list, 100);int j = 0;// 对大集合里面的每一个小集合进行操作for (List<String> obj : temps) {System.out.println(String.format("row:%s -> size:%s,data:%s", ++j, obj.size(), obj));}}}

造数据，进行多线程异步插入

public int batchInsertWay() throws Exception {log.info("开始批量操作.........");Random rand = new Random();List<Student> list = new ArrayList<>();//造100万条数据for (int i = 0; i < 1000003; i++) {Student student=new Student();student.setStudentName("大明："+i);student.setAddr("上海:"+rand.nextInt(9) * 1000);student.setAge(rand.nextInt(1000));student.setPhone("134"+rand.nextInt(9) * 1000);list.add(student);}//2、开始多线程异步批量导入long startTime = System.currentTimeMillis(); // 开始时间//boolean a=studentService.batchInsert(list);List<List<Student>> list1=SplitListUtils.pagingList(list,100);  //拆分集合CountDownLatch countDownLatch = new CountDownLatch(list1.size());for (List<Student> list2 : list1) {asyncService.executeAsync(list2,studentService,countDownLatch);}try {countDownLatch.await(); //保证之前的所有的线程都执行完成，才会走下面的；long endTime = System.currentTimeMillis(); //结束时间log.info("一共耗时time: " + (endTime - startTime) / 1000 + " s");// 这样就可以在下面拿到所有线程执行完的集合结果} catch (Exception e) {log.error("阻塞异常:"+e.getMessage());}return list.size();}