java - 公共(public)资源池 : How to instantiate a concrete pool?

Question

我已将 commons-pooling-1.6.jar 添加到我的类路径并尝试实例化一个 StackObjectPool 但每次都失败:

// Deprecated.
ObjectPool<T> oPool = new StackObjectPool<T>();

// Error: Cannot instantiate the type BasePoolableObjectFactory<T>.
PoolableObjectFactory<T> oFact = new BasePoolableObjectFactory<T>();
ObjectPool<T> oPool = new StackObjectPool<T>(oFact);

这是完全弃用的 API 吗？如果是这样，Commons Pooling 有哪些开源替代方案？否则，如何实例化 StackObjectPool？

Answer 1

您需要编写自己的工厂，可能会扩展 BasePoolableObjectFactory。有关详细信息，请参见此处:http://commons.apache.org/pool/examples.html

下面是创建 StringBuffers 的 PoolableObjectFactory 实现:

import org.apache.commons.pool.BasePoolableObjectFactory; 

public class StringBufferFactory extends BasePoolableObjectFactory<StringBuffer> { 
    // for makeObject we'll simply return a new buffer 
    public StringBuffer makeObject() { 
        return new StringBuffer(); 
    } 

    // when an object is returned to the pool,  
    // we'll clear it out 
    public void passivateObject(StringBuffer buf) { 
        buf.setLength(0); 
    } 

    // for all other methods, the no-op  
    // implementation in BasePoolableObjectFactory 
    // will suffice 
}

然后按如下方式使用:

new StackObjectPool<StringBuffer>(new StringBufferFactory())