android中使用对象池 ----- Pools

来源：互联网发布：日程软件知乎电脑编辑：程序博客网时间：2024/06/15 18:10

最近在做音频直播间的优化，发现Socket聊天部分，接收到的信息，传递到adapter中时，总是new一个对象，再把信息数据封装进去传递给adapter。
这时候想这个new对象的动作其实是可以优化，试想直播间的聊天吹水是多么频繁，2000多号人在直播间聊天的时候，刷刷刷的满屏滚动的聊天信息，不停的new对象，给GC带来的压力可想而知。
所以搜了一下关于对象池方面的资料，记录如下：

1、Apache Commons-pool2
一开始搜索到这个common pool2框架，在Eclipse跑了下demo，发现还蛮不错的，很多配置属性，可控制；
可惜，移植到android上时，TMD不能用….因为pool2使用了JMX，而android虚拟机中没有jmx….大写的尴尬！
不能用归不能用了，笔记还是记下，也许哪天就可以用上了：
Apache Commons-pool2简记

2.Pools
上面的common-pool2不能用后，又搜索了解android方面的对象池资料，发现其实android自己就有pools工具类，在android.support.v4.util.Pools。
Pools源码很简短：

/** * 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();//获取对象        /**         * 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);//释放对象    }    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);            }        }    }}

源码很简单，主要有Pool接口、SimplePool、SynchronizedPool组成，官方也给出了demo，直接上我的使用封装：

import android.support.v4.util.Pools;import com.sing.client.live_audio.entity.BaseChatMsgEntity;/** * Created by mayi on 17/4/8. * * @Autor CaiWF * @Email 401885064@qq.com * @TODO UIGeter对象池 */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;    }    //对象池中获取对象    public static BaseChatMsgEntity getUIGetObject() {        try {            BaseChatMsgEntity baseChatMsgEntity = getInstance().getPool().acquire();            return baseChatMsgEntity == null ? new BaseChatMsgEntity() : baseChatMsgEntity;        } catch (Exception e) {//            e.printStackTrace();            return new BaseChatMsgEntity();        }    }    //返回对象    public static void returnObject(BaseChatMsgEntity uiGeter) {        try {            getInstance().getPool().release(uiGeter);        } catch (Exception e) {            e.printStackTrace();        }    }}

仅此做个笔记，有什么不对的，欢迎指点！

0 0