最近在做音訊直播間的優化，發現Socket聊天部分，接收到的資訊，傳遞到adapter中時，總是new一個物件，再把資訊資料封裝進去傳遞給adapter。
這時候想這個new物件的動作其實是可以優化，試想直播間的聊天吹水是多麼頻繁，2000多號人在直播間聊天的時候，刷刷刷的滿屏滾動的聊天資訊，不停的new物件，給GC帶來的壓力可想而知。
所以搜了一下關於物件池方面的資料，記錄如下：

1、Apache Commons-pool2
一開始搜尋到這個common pool2框架，在Eclipse跑了下demo，發現還蠻不錯的，很多配置屬性，可控制；
可惜，移植到android上時，TMD不能用….因為pool2使用了JMX，而android虛擬機器中沒有jmx….大寫的尷尬！
不能用歸不能用了，筆記還是記下，也許哪天就可以用上了：

2.Pools
上面的common-pool2不能用後，又搜尋瞭解android方面的物件池資料，發現其實android自己就有pools工具類，在android.support.v4.util.Pools。
Pools原始碼很簡短：

/**
 * Helper class for creating pools of objects. An example use looks like this:
 * <pre>
 * public class MyPooledClass {//官方Pools使用demo
 *
 *     private static final SynchronizedPool<MyPooledClass> sPool =
 *             new SynchronizedPool<MyPooledClass>(10);
 *
 *     public static MyPooledClass obtain() {
 *         MyPooledClass instance = sPool.acquire();
 *         return (instance != null) ? instance : new MyPooledClass();
 *     }
 *
 *     public void recycle() {
 *          // Clear state if needed.
 *          sPool.release(this);
 *     }
 *
 *     . . .
 * }
 * </pre>
 *
 */
 

public final class Pools {

    /**
     * Interface for managing a pool of objects.
     *
     * @param <T> The pooled type.
     */
    public static interface Pool<T> {

        /**
         * @return An instance from the pool if such, null otherwise.
         */
        public T acquire();//獲取物件
 


        /**
         * Release an instance to the pool.
         *
         * @param instance The instance to release.
         * @return Whether the instance was put in the pool.
         *
         * @throws IllegalStateException If the instance is already in the pool.
         */
        public boolean release(T instance);//釋放物件
    }

    private Pools() {
        /* do nothing - hiding constructor */
    }

    /**
     * Simple (non-synchronized) pool of objects.
     *
     * @param <T> The pooled type.
     */
    public static class SimplePool<T> implements Pool<T> {
        private final Object[] mPool;

        private int mPoolSize;

        /**
         * Creates a new instance.
         *
         * @param maxPoolSize The max pool size.
         *
         * @throws IllegalArgumentException If the max pool size is less than zero.
         */
        public SimplePool(int maxPoolSize) {
            if (maxPoolSize <= 0) {
                throw new IllegalArgumentException("The max pool size must be > 0");
            }
            mPool = new Object[maxPoolSize];
        }

        @Override
        @SuppressWarnings("unchecked")
        public T acquire() {
            if (mPoolSize > 0) {
                final int lastPooledIndex = mPoolSize - 1;
                T instance = (T) mPool[lastPooledIndex];
                mPool[lastPooledIndex] = null;
                mPoolSize--;
                return instance;
            }
            return null;
        }

        @Override
        public boolean release(T instance) {
            if (isInPool(instance)) {
                throw new IllegalStateException("Already in the pool!");
            }
            if (mPoolSize < mPool.length) {
                mPool[mPoolSize] = instance;
                mPoolSize++;
                return true;
            }
            return false;
        }

        private boolean isInPool(T instance) {
            for (int i = 0; i < mPoolSize; i++) {
                if (mPool[i] == instance) {
                    return true;
                }
            }
            return false;
        }
    }

    /**
     * Synchronized) pool of objects.
     *
     * @param <T> The pooled type.
     */
    public static class SynchronizedPool<T> extends SimplePool<T> {
        private final Object mLock = new Object();

        /**
         * Creates a new instance.
         *
         * @param maxPoolSize The max pool size.
         *
         * @throws IllegalArgumentException If the max pool size is less than zero.
         */
        public SynchronizedPool(int maxPoolSize) {
            super(maxPoolSize);
        }

        @Override
        public T acquire() {
            synchronized (mLock) {
                return super.acquire();
            }
        }

        @Override
        public boolean release(T element) {
            synchronized (mLock) {
                return super.release(element);
            }
        }
    }
}

原始碼很簡單，主要有Pool介面、SimplePool、SynchronizedPool組成，官方也給出了demo，直接上我的使用封裝：

import android.support.v4.util.Pools;
import com.sing.client.live_audio.entity.BaseChatMsgEntity;

/**
 * Created by mayi on 17/4/8.
 *
 * @Autor CaiWF
 * @Email [email protected]
 * @TODO UIGeter物件池
 */

public class UIGeterPoolModule {
    private Pools.SynchronizedPool<BaseChatMsgEntity> pool;
    private static UIGeterPoolModule uiGeterPoolModule;

    private UIGeterPoolModule() {
        pool = new Pools.SynchronizedPool<BaseChatMsgEntity>(55);
    }

    public static synchronized UIGeterPoolModule getInstance() {
        if (uiGeterPoolModule == null) {
            uiGeterPoolModule = new UIGeterPoolModule();
        }
        return uiGeterPoolModule;
    }

    public Pools.SynchronizedPool<BaseChatMsgEntity> getPool() {
        return pool;
    }

    //物件池中獲取物件
    public static BaseChatMsgEntity getUIGetObject() {
        try {
            BaseChatMsgEntity baseChatMsgEntity = getInstance().getPool().acquire();
            return baseChatMsgEntity == null ? new BaseChatMsgEntity() : baseChatMsgEntity;
        } catch (Exception e) {
//            e.printStackTrace();
            return new BaseChatMsgEntity();
        }
    }

    //返回物件
    public static void returnObject(BaseChatMsgEntity uiGeter) {
        try {
            getInstance().getPool().release(uiGeter);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}

僅此做個筆記，有什麼不對的，歡迎指點！