myobjectpool.java

高质量Java程序设计 源代码

package net.betterjava.performance.pool.impl;
import java.util.Iterator;
import org.apache.commons.pool.PoolableObjectFactory;
import org.apache.commons.pool.ObjectPool;
import java.util.List;
import java.util.LinkedList;

public class MyObjectPool implements ObjectPool {
	private List pool = new LinkedList();
	private PoolableObjectFactory factory;

	public MyObjectPool() {
		super();
	}

	public MyObjectPool(PoolableObjectFactory factory) {
		super();
		this.factory = factory;
	}

	public synchronized Object borrowObject() throws Exception {
		if (pool.isEmpty())
			return factory.makeObject();
		else {
			return pool.remove(0);
		}
	}

	public synchronized void clear() throws Exception, UnsupportedOperationException {
		Iterator it = pool.iterator();
		while (it.hasNext()) {
			try {
				factory.destroyObject(it.next());
			} catch (Exception e) {

			}
			it.remove();
		}
		pool.clear();
		notifyAll();
	}

	public synchronized void close() throws Exception {
		clear();
		pool = null;
		factory = null;
	}

	public int getNumActive() throws UnsupportedOperationException {
		return 0;
	}

	public int getNumIdle() throws UnsupportedOperationException {
		return 0;
	}

	public synchronized void returnObject(Object obj) throws Exception {
		pool.add(0, obj);
	}

	public void setFactory(PoolableObjectFactory factory)
		throws UnsupportedOperationException, IllegalStateException {
		this.factory = factory;
	}
}