Reactor.java

package us.codecraft.netty.reactor;

import java.io.IOException;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.util.Iterator;
import java.util.Set;

/**
 * @author yihua.huang@dianping.com
 */
public class Reactor implements Runnable {

	Selector selector;

	public Reactor() throws IOException {
		selector = Selector.open();
	}

	public void run() {
		try {
			while (!Thread.interrupted()) {
                //循环，等待事件
				selector.select();
				Set selected = selector.selectedKeys();
				Iterator it = selected.iterator();
				while (it.hasNext())
                    //调用handler，处理事件
					dispatch((SelectionKey) (it.next()));
				selected.clear();
			}
		} catch (IOException ex) { /* ... */
		}
	}

	void dispatch(SelectionKey k) {
		Runnable r = (Runnable) (k.attachment());
		if (r != null)
			r.run();
	}
}