ThreadPoolExecutor VS ThreadPoolTaskExecutor
ThreadPoolTaskExecutor是对ThreadPoolExecutor进行了封装处理。
配置文件application.yml
yml
# 异步线程配置 自定义使用参数
async:
executor:
thread:
core_pool_size: 10
max_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s
name:
prefix: async-thread- # 配置线程池中的线程的名称前缀配置类
java
@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 s
executor.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
java
//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
java
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
java
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();
}
