1、在OKHttp中需要一個(gè)隊(duì)列來(lái)保存不同的請(qǐng)求

/**
 * 保存HttpConnection隊(duì)列
 */
private Deque<HttpConnection> mConnections = new ArrayDeque<>();

2、在每次請(qǐng)求前從線程池里檢查是否有超時(shí)的連接，將超時(shí)的連接從線程池移除

//在這里將連接放入線程池
public void put(HttpConnection httpConnection) {
    if (!cleanupRunning) {
        cleanupRunning = true;
        EXECUTOR.execute(cleanupRunnable);
    }
    mConnections.add(httpConnection);
}

/**
 * 清理線程
 */
private Runnable cleanupRunnable = () -> {
    while(true) {
        //等待再次檢查時(shí)間間隔
        long waitTime = cleanup(System.currentTimeMillis());

        if(waitTime == -1) {
            return;
        }

        if(waitTime > 0) {
            synchronized (ConnectionPool.this){
                try {
                    ConnectionPool.this.wait(waitTime);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }

    }
};


   //在這里清理超時(shí)請(qǐng)求
   private long cleanup(long nowTime) {
    //記錄最長(zhǎng)閑置時(shí)間
    long longLastIdlTime = -1;
    synchronized (this) {
        //遍歷連接隊(duì)列
        Iterator<HttpConnection> iterator = mConnections.iterator();
        while (iterator.hasNext()) {
            HttpConnection next = iterator.next();
            //閑置時(shí)間
            long idlDurationTime = nowTime - next.getLastUseTime();
            if (idlDurationTime > keepAlive) {
                iterator.remove();
                next.close();
                Log.d(TAG, "cleanup —> 超過(guò)閑置時(shí)間橘蜜，移出線程池");
                continue;
            }

            //最長(zhǎng)的閑置時(shí)間
            if (longLastIdlTime < idlDurationTime) {
                longLastIdlTime = idlDurationTime;
            }
        }
        //返回等待時(shí)間
        if (longLastIdlTime >= 0) {
            return keepAlive - longLastIdlTime;
        }
        //連接池沒(méi)有連接羡藐，可以退出
        cleanupRunning = false;
        return longLastIdlTime;
    }
}

3、清理線程由線程池管理并將線程設(shè)為守護(hù)線程

/**
 * 定義一個(gè)線程池,用來(lái)執(zhí)行清理線程
 */
private static final Executor EXECUTOR 
    = new ThreadPoolExecutor(
        0, //最小并發(fā)線程數(shù)。
        Integer.MAX_VALUE, //線程池中允許的最大線程數(shù)
        60L, //當(dāng)線程的數(shù)目大于corePoolSize時(shí)栽燕，線程的最大存活時(shí)間。
        TimeUnit.SECONDS, //時(shí)間單位
        new SynchronousQueue<>(),//在執(zhí)行任務(wù)之前用于保存任務(wù)的隊(duì)列
        r -> {//創(chuàng)建新的線程使用的工廠
           Thread thread = new Thread(r, "ConnectionPool");
           thread.setDaemon(true);
           return thread;
});

4奈籽、線程池的復(fù)用，遍歷請(qǐng)求隊(duì)列的請(qǐng)求煮甥，判斷是否有相同的請(qǐng)求

/**
 * 獲得可復(fù)用的連接池
 *
 * @param host
 * @param port
 * @return
 */
public HttpConnection get(String host, int port) {
    Iterator<HttpConnection> iterator = mConnections.iterator();
    while (iterator.hasNext()) {
        HttpConnection next = iterator.next();
        //判斷線程池里是否存在相同的請(qǐng)求地址
        if (next.isSameAdress(host, port)) {
            iterator.remove();
            return next;
        }
    }
    return null;
}


public boolean isSameAdress(String host, int port) {
    if (TextUtils.isEmpty(host) || port < 0) {
        throw new NullPointerException("Host OR Port maybe null point,Please Check it once again");
    }
    if (mSocket == null) {
        return false;
    }
    return TextUtils.equals(host, mSocket.getInetAddress().getHostName()) && port == mSocket.getPort();
}