自定义线程池管理类

import java.util.concurrent.BlockingQueue;import java.util.concurrent.LinkedBlockingQueue;import java.util.concurrent.ThreadFactory;import java.util.concurrent.ThreadPoolExecutor;import java.util.concurrent.TimeUnit;import java.util.concurrent.atomic.AtomicInteger;public class ThreadPoolManager {    private static ThreadPoolManager mInstance;    private int corePoolSize;    /**     * 最大线程池数量，表示当缓冲队列满的时候能继续容纳的等待任务的数量     */    private int maximumPoolSize;    /**     * 存活时间     */    private long keepAliveTime = 1;    private TimeUnit unit = TimeUnit.HOURS;    private ThreadPoolExecutor executor;    // 缓冲队列    private static BlockingQueue workQueue = null;    public static ThreadPoolManager getInstance() {        if (mInstance == null){            synchronized (ThreadPoolManager.class){                if (mInstance == null){                    mInstance = new ThreadPoolManager();                    mInstance.init();                }            }        }        return mInstance;    }    private void init(){        //给corePoolSize赋值：当前设备可用处理器核心数*2 + 1,能够让cpu的效率得到最大程度执行（有研究论证的）        corePoolSize = Runtime.getRuntime().availableProcessors() * 2 + 1;        maximumPoolSize = corePoolSize;        workQueue = new LinkedBlockingQueue(100);        executor = new ThreadPoolExecutor(                //当某个核心任务执行完毕，会依次从缓冲队列中取出等待任务                corePoolSize,                //5,先corePoolSize,然后new LinkedBlockingQueue(),然后maximumPoolSize,但是它的数量是包含了corePoolSize的                maximumPoolSize,                //表示的是maximumPoolSize当中等待任务的存活时间                keepAliveTime,                unit,                //缓冲队列，用于存放等待任务，Linked的先进先出//                new LinkedBlockingQueue(),                workQueue,                //创建线程的工厂                //  Executors.defaultThreadFactory(),                new DefaultThreadFactory(Thread.NORM_PRIORITY, "tiaoba-pool-"),                //用来对超出maximumPoolSize的任务的处理策略                new ThreadPoolExecutor.AbortPolicy()        );    }    private static class DefaultThreadFactory implements ThreadFactory {        /**         * 线程池的计数         */        private static final AtomicInteger poolNumber = new AtomicInteger(1);        /**         * 线程的计数         */        private final AtomicInteger threadNumber = new AtomicInteger(1);        private final ThreadGroup group;        private final String namePrefix;        private final int threadPriority;        DefaultThreadFactory(int threadPriority, String threadNamePrefix) {            this.threadPriority = threadPriority;            //默认线程组            this.group = Thread.currentThread().getThreadGroup();            namePrefix = threadNamePrefix + poolNumber.getAndIncrement() + "-thread-";        }        @Override        public Thread newThread(Runnable r) {            Thread t = new Thread(group, r, namePrefix + threadNumber.getAndIncrement(), 0);            //isDaemon() 测试该线程是否为守护线程            if (t.isDaemon()) {                t.setDaemon(false);            }            t.setPriority(threadPriority);            return t;        }    }    public void execute(Runnable runnable) {        if (executor == null){            init();        }        if (runnable != null){            executor.execute(runnable);        }    }}
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