【Java工具类】线程池工厂工具

小灰灰 2022-11-19 04:11 110阅读 0赞

import java.util.concurrent.*;
    import java.util.concurrent.atomic.AtomicInteger;
    /** * 线程池工厂工具 * */
    public class ThreadPoolFactory { 
    
        /** * 生成固定大小的线程池 * * @param threadName 线程名称 * @return 线程池 */
        public static ExecutorService createFixedThreadPool(String threadName) { 
            AtomicInteger threadNumber = new AtomicInteger(0);
            return new ThreadPoolExecutor(
                    // 核心线程数
                    desiredThreadNum(),
                    // 最大线程数
                    desiredThreadNum() * 2,
                    // 空闲线程存活时间
                    60L,
                    // 空闲线程存活时间单位
                    TimeUnit.SECONDS,
                    // 工作队列
                    new ArrayBlockingQueue<>(1024),
                    // 线程工厂
                    new ThreadFactory() { 
                        @Override
                        public Thread newThread(Runnable r) { 
                            return new Thread(r, threadName + "-" + threadNumber.getAndIncrement());
                        }
                    },
                    // 拒绝策略
                    new RejectedExecutionHandler() { 
                        @Override
                        public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) { 
                            if (!executor.isShutdown()) { 
                                try { 
                                    //尝试阻塞式加入任务队列
                                    executor.getQueue().put(r);
                                } catch (Exception e) { 
                                    //保持线程的中断状态
                                    Thread.currentThread().interrupt();
                                }
                            }
                        }
                    });
        }
    
        /** * 理想的线程数，使用 2倍cpu核心数 */
        public static int desiredThreadNum() { 
            return Runtime.getRuntime().availableProcessors() * 2;
        }
    
        public static void main(String[] args) { 
            ExecutorService executorService = ThreadPoolFactory.createFixedThreadPool("myThread");
    
            for (int i = 0; i < 100; i++) { 
                int finalI = i;
                executorService.execute(new Runnable() { 
                    @Override
                    public void run() { 
                        System.out.println(Thread.currentThread().getName()+"=>打印:" + finalI);
                    }
                });
            }
    
            executorService.shutdown();
        }
    }

执行结果  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxODc3NzI4NzE1_size_16_color_FFFFFF_t_70]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxODc3NzI4NzE1_size_16_color_FFFFFF_t_70]: /images/20221022/ee1f274eea9f416abd2fc2f4f0f242c3.png