自定义线程池配置

package com.woniu.friend.utils;


import org.jetbrains.annotations.NotNull;

import java.util.concurrent.*;

public class ThreadFactoryUtils {


    // volatile 防止指令重排，和保证内存可见性
    private static  volatile ThreadPoolExecutor threadPoolExecutor;

    // 获取当前机器的核心线程数
    private final static int cpuCores = Runtime.getRuntime().availableProcessors();

    // 私有化构造器
    private ThreadFactoryUtils(){

    }


    // 单例模式创建线程池，双层判断防止并发
    public static ThreadPoolExecutor getThreadPoolExecutor(){

        if(threadPoolExecutor == null){
            synchronized (ThreadFactoryUtils.class){
                if(threadPoolExecutor == null){
                    threadPoolExecutor = new ThreadPoolExecutor(
                            cpuCores, // 核心线程数
                            cpuCores * 2, //最大线程数
                            60, // 空线程最大存活时间
                            TimeUnit.SECONDS,
                            new LinkedBlockingQueue<>(), // 阻塞队列
                            new CustomThreadFactory(),  // 自定义线程工厂
                            new ThreadPoolExecutor.AbortPolicy() // 拒绝策略
                            );
                }
            }
        }
        return threadPoolExecutor;
    }


    static class CustomThreadFactory implements ThreadFactory {

        @Override
        public Thread newThread(@NotNull Runnable runnable) {
            return new Thread(runnable);
        }
    }

}