AIO，在NIO的基础上引入了异步通道的概念，并提供了异步文件和异步套接字通道的实现，从而在真正意义上实现了异步非阻塞，这是在jdk1.7及以后才有的。
AIO不需要通过类似NIO的多路复用器对注册的通道进行轮训操作，即可实现异步读写，从而简化了NIO的编程模型。也可以称为NIO2.0.这种模式才是真正的异步非阻塞模型。
AsynchonousServerSocketChannel
AsynchonousSocketChannel
代码：
import java.net.InetSocketAddress; import java.nio.channels.AsynchronousChannelGroup; import java.nio.channels.AsynchronousServerSocketChannel; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; public class Server { //线程池 private ExecutorService executorService; //线程组 private AsynchronousChannelGroup threadGroup; //服务器通道 public AsynchronousServerSocketChannel assc; public Server(int port){ try { //创建一个缓存池 executorService = Executors.newCachedThreadPool(); //创建线程组 threadGroup = AsynchronousChannelGroup.withCachedThreadPool(executorService, 1); //创建服务器通道 assc = AsynchronousServerSocketChannel.open(threadGroup); //进行绑定 assc.bind(new InetSocketAddress(port)); System.out.println("server start , port : " + port); //进行阻塞 assc.accept(this, new ServerCompletionHandler()); //一直阻塞 不让服务器停止 Thread.sleep(Integer.MAX_VALUE); } catch (Exception e) { e.printStackTrace(); } } public static void main(String[] args) { Server server = new Server(8765); } }
import java.nio.ByteBuffer; import java.nio.channels.AsynchronousSocketChannel; import java.nio.channels.CompletionHandler; import java.util.concurrent.ExecutionException; public class ServerCompletionHandler implements CompletionHandler<AsynchronousSocketChannel, Server> { @Override public void completed(AsynchronousSocketChannel asc, Server attachment) { //当有下一个客户端接入的时候 直接调用Server的accept方法，这样反复执行下去，保证多个客户端都可以阻塞 attachment.assc.accept(attachment, this); read(asc); } private void read(final AsynchronousSocketChannel asc) { //读取数据 ByteBuffer buf = ByteBuffer.allocate(1024); asc.read(buf, buf, new CompletionHandler<Integer, ByteBuffer>() { @Override public void completed(Integer resultSize, ByteBuffer attachment) { //进行读取之后,重置标识位 attachment.flip(); //获得读取的字节数 System.out.println("Server -> " + "收到客户端的数据长度为:" + resultSize); //获取读取的数据 String resultData = new String(attachment.array()).trim(); System.out.println("Server -> " + "收到客户端的数据信息为:" + resultData); String response = "服务器响应, 收到了客户端发来的数据: " + resultData; write(asc, response); } @Override public void failed(Throwable exc, ByteBuffer attachment) { exc.printStackTrace(); } }); } private void write(AsynchronousSocketChannel asc, String response) { try { ByteBuffer buf = ByteBuffer.allocate(1024); buf.put(response.getBytes()); buf.flip(); asc.write(buf).get(); } catch (InterruptedException e) { e.printStackTrace(); } catch (ExecutionException e) { e.printStackTrace(); } } @Override public void failed(Throwable exc, Server attachment) { exc.printStackTrace(); } }
import java.io.UnsupportedEncodingException; import java.net.InetSocketAddress; import java.nio.ByteBuffer; import java.nio.channels.AsynchronousSocketChannel; import java.util.concurrent.ExecutionException; public class Client implements Runnable{ private AsynchronousSocketChannel asc ; public Client() throws Exception { asc = AsynchronousSocketChannel.open(); } public void connect(){ asc.connect(new InetSocketAddress("127.0.0.1", 8765)); } public void write(String request){ try { asc.write(ByteBuffer.wrap(request.getBytes())).get(); read(); } catch (Exception e) { e.printStackTrace(); } } private void read() { ByteBuffer buf = ByteBuffer.allocate(1024); try { asc.read(buf).get(); buf.flip(); byte[] respByte = new byte[buf.remaining()]; buf.get(respByte); System.out.println(new String(respByte,"utf-8").trim()); } catch (InterruptedException e) { e.printStackTrace(); } catch (ExecutionException e) { e.printStackTrace(); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } } @Override public void run() { while(true){ } } public static void main(String[] args) throws Exception { Client c1 = new Client(); c1.connect(); Client c2 = new Client(); c2.connect(); Client c3 = new Client(); c3.connect(); new Thread(c1, "c1").start(); new Thread(c2, "c2").start(); new Thread(c3, "c3").start(); Thread.sleep(1000); c1.write("c1 aaa"); c2.write("c2 bbbb"); c3.write("c3 ccccc"); } }
打印：
server端：
server start , port : 8765 Server -> 收到客户端的数据长度为:6 Server -> 收到客户端的数据信息为:c1 aaa Server -> 收到客户端的数据长度为:7 Server -> 收到客户端的数据信息为:c2 bbbb Server -> 收到客户端的数据长度为:8 Server -> 收到客户端的数据信息为:c3 ccccc
client端：
服务器响应, 收到了客户端发来的数据: c1 aaa 服务器响应, 收到了客户端发来的数据: c2 bbbb 服务器响应, 收到了客户端发来的数据: c3 ccccc
简单解读：
对于ServerCompletionHandler的Complent和fail方法的场景分别是，当服务器端接入了客户端channel后，就会调用complete方法，参数为(AsynchronousSocketChannel asc, Server attachment），就是一个客户端的channel和服务器端实例。
需要注意：
@Override public void completed(AsynchronousSocketChannel asc, Server attachment) { //当有下一个客户端接入的时候 直接调用Server的accept方法，这样反复执行下去，保证多个客户端都可以阻塞 attachment.assc.accept(attachment, this); read(asc); }
一定要先调用attachment.assc.accept(attachment, this);这个异步方法，保证后来的客户端可以正常接入。
异步方法：
转载请标明出处:网络编程之每天学习一点点[day5]-----aio编程