AIO通信
一、AIO简介
HDK推出的NIO2.0也叫AIO引入了新的异步通道的概念，并提供了异步文件通道和异步套接字通道的实现。AIO的异步套接字通道是真正的异步非阻塞IO，对应于UNIX网络编程中的事件驱动IO（AIO）。它不需要通过多路复用器Selector对注册的通道进行轮询操作即可实现异步读写，从而简化了NIO的编程模型。
二、代码实例
2.1 服务端
TimeServer.java
package com.wangjun.io.aio;
/**
* @author wangjun
* @date 2020-04-01
* @version 1.0
*/
public class TimeServer {
public static void main(String[] args) {
int port = 8080;
AsynTimeServerHandler timeServer = new AsynTimeServerHandler(port);
new Thread(timeServer, "AIO-AsynTimeServerHandler-001").start();
}
}AsynTimeServerHandler.java
package com.wangjun.io.aio;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.channels.AsynchronousServerSocketChannel;
import java.util.concurrent.CountDownLatch;
/**
* @author wangjun
* @date 2020-04-01
* @version 1.0
*/
public class AsynTimeServerHandler implements Runnable {
CountDownLatch latch;
AsynchronousServerSocketChannel asynchronousServerSocketChannel;
public AsynTimeServerHandler(int port) {
try {
asynchronousServerSocketChannel = AsynchronousServerSocketChannel.open();
asynchronousServerSocketChannel.bind(new InetSocketAddress(port));
System.out.println("The time server start in port:" + port);
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void run() {
latch = new CountDownLatch(1);
doAccept();
try {
latch.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public void doAccept() {
asynchronousServerSocketChannel.accept(this, new AcceptCompletionHandler());
}
}AcceptCompletionHandler.java
package com.wangjun.io.aio;
import java.nio.ByteBuffer;
import java.nio.channels.AsynchronousSocketChannel;
import java.nio.channels.CompletionHandler;
/**
* @author wangjun
* @date 2020-04-01
* @version 1.0
*/
public class AcceptCompletionHandler implements CompletionHandler<AsynchronousSocketChannel, AsynTimeServerHandler> {
@Override
public void completed(AsynchronousSocketChannel result, AsynTimeServerHandler attachment) {
attachment.asynchronousServerSocketChannel.accept(attachment, this);
ByteBuffer buffer = ByteBuffer.allocate(1024);
result.read(buffer, buffer, new ReadCompletionHandler(result));
}
@Override
public void failed(Throwable exc, AsynTimeServerHandler attachment) {
exc.printStackTrace();
attachment.latch.countDown();
}
}ReadCompletionHandler.java
package com.wangjun.io.aio;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.nio.ByteBuffer;
import java.nio.channels.AsynchronousSocketChannel;
import java.nio.channels.CompletionHandler;
import java.util.Date;
/**
* @author wangjun
* @date 2020-04-01
* @version 1.0
*/
public class ReadCompletionHandler implements CompletionHandler<Integer, ByteBuffer> {
private AsynchronousSocketChannel channel;
public ReadCompletionHandler(AsynchronousSocketChannel channel) {
if(this.channel == null) {
this.channel = channel;
}
}
@Override
public void completed(Integer result, ByteBuffer attachment) {
attachment.flip();
byte[] body = new byte[attachment.remaining()];
attachment.get(body);
try {
String req = new String(body, "UTF-8");
System.out.println("服务端收到的命令是：" + req);
String currentTime = "QUERY TIME ORDER".equalsIgnoreCase(req)
? new Date(System.currentTimeMillis()).toString()
: "BAD ORDER";
doWrite(currentTime);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
private void doWrite(String currentTime) {
if(currentTime != null && currentTime.trim().length() > 0) {
byte[] bytes = currentTime.getBytes();
ByteBuffer writeBuffer = ByteBuffer.allocate(bytes.length);
writeBuffer.put(bytes);
writeBuffer.flip();
channel.write(writeBuffer, writeBuffer, new CompletionHandler<Integer, ByteBuffer>() {
@Override
public void completed(Integer result, ByteBuffer buffer) {
//如果没有发送完成，继续发送
if(buffer.hasRemaining()) {
channel.write(buffer, buffer, this);
}
}
@Override
public void failed(Throwable exc, ByteBuffer attachment) {
try {
channel.close();
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
}
@Override
public void failed(Throwable paramThrowable, ByteBuffer paramA) {
try {
this.channel.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}2.2 客户端
TimeClient.java
package com.wangjun.io.aio;
public class TimeClient {
public static void main(String[] args) throws InterruptedException {
int port = 8080;
new Thread(new AsynTimeClientHandler("127.0.0.1", port), "AsynTimeClientHandler-001").start();
}
}AsynTimeClientHandler.java
package com.wangjun.io.aio;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.channels.AsynchronousSocketChannel;
import java.nio.channels.CompletionHandler;
import java.util.concurrent.CountDownLatch;
/**
* @author wangjun
* @date 2020-04-01
* @version 1.0
*/
public class AsynTimeClientHandler implements CompletionHandler<Void, AsynTimeClientHandler>, Runnable {
private String host;
private int port;
private AsynchronousSocketChannel client;
private CountDownLatch latch;
public AsynTimeClientHandler(String host, int port) {
this.host = host;
this.port = port;
try {
client = AsynchronousSocketChannel.open();
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void run() {
latch = new CountDownLatch(1);
client.connect(new InetSocketAddress(host, port), this, this);
try {
latch.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
try {
client.close();
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void completed(Void result, AsynTimeClientHandler attachment) {
byte[] req = "QUERY TIME ORDER".getBytes();
ByteBuffer writeBuffer = ByteBuffer.allocate(req.length);
writeBuffer.put(req);
writeBuffer.flip();
client.write(writeBuffer, writeBuffer, new CompletionHandler<Integer, ByteBuffer>() {
@Override
public void completed(Integer result, ByteBuffer buffer) {
if(buffer.hasRemaining()) {
client.write(buffer, buffer, this);
}else {
ByteBuffer readBuffer = ByteBuffer.allocate(1024);
client.read(readBuffer, readBuffer, new CompletionHandler<Integer, ByteBuffer>() {
@Override
public void completed(Integer result, ByteBuffer buffer) {
buffer.flip();
byte[] bytes = new byte[buffer.remaining()];
buffer.get(bytes);
String body;
try {
body = new String(bytes, "UTF-8");
System.out.println("现在是：" + body);
latch.countDown();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
@Override
public void failed(Throwable exc, ByteBuffer attachment) {
try {
client.close();
latch.countDown();
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
}
@Override
public void failed(Throwable exc, ByteBuffer attachment) {
try {
client.close();
latch.countDown();
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
@Override
public void failed(Throwable exc, AsynTimeClientHandler attachment) {
exc.printStackTrace();
try {
client.close();
latch.countDown();
} catch (IOException e) {
e.printStackTrace();
}
}
}Last updated