public class NIOServer {
private Selector selector;
public void startServer(int port) throws IOException {
ServerSocketChannel serverChannel = ServerSocketChannel.open();
// 设置通道为非阻塞
serverChannel.configureBlocking(false);
serverChannel.socket().bind(new InetSocketAddress(port));
this.selector = Selector.open();
serverChannel.register(selector, SelectionKey.OP_ACCEPT);
}
public void listen() throws IOException {
while (true) {
//当注册的事件到达时，方法返回；否则,该方法会一直阻塞
selector.select();
Iterator<SelectionKey> it = this.selector.selectedKeys().iterator();
while (it.hasNext()) {
SelectionKey key = (SelectionKey) it.next();
// 此处一定要删除
it.remove();
if (key.isAcceptable()) {
ServerSocketChannel server = (ServerSocketChannel) key
.channel();
SocketChannel channel = server.accept();
System.out.println("remote socket is:"+channel.socket().getInetAddress());
channel.configureBlocking(false);
channel.write(ByteBuffer.wrap(new String("send one msg to client").getBytes()));
channel.register(this.selector, SelectionKey.OP_READ);
} else if (key.isReadable()) {
read(key);
}
}
}
}
public void read(SelectionKey key) throws IOException{
SocketChannel channel = (SocketChannel) key.channel();
ByteBuffer buffer = ByteBuffer.allocate(1024);
int len = channel.read(buffer);
byte[] data = new byte[len];
System.arraycopy(buffer.array(), 0, data, 0, len);
String msg = new String(data).trim();
System.out.println("server receive one msg:"+msg);
ByteBuffer outBuffer = ByteBuffer.wrap(msg.getBytes());
channel.write(outBuffer);
}
public static void main(String[] args) throws IOException {
NIOServer server = new NIOServer();
server.startServer(8080);
server.listen();
}
}
NIO客户端代码：
public class NIOClient {
private Selector selector;
public void initClient(String ip,int port) throws IOException {
SocketChannel channel = SocketChannel.open();
channel.configureBlocking(false);
this.selector = Selector.open();
channel.connect(new InetSocketAddress(ip,port));
channel.register(selector, SelectionKey.OP_CONNECT);
}
public void listen() throws IOException {
while (true) {
selector.select();
Iterator<SelectionKey> it = this.selector.selectedKeys().iterator();
while (it.hasNext()) {
SelectionKey key = (SelectionKey) it.next();
it.remove();
if (key.isConnectable()) {
SocketChannel channel = (SocketChannel) key.channel();
if(channel.isConnectionPending()){
channel.finishConnect();
}
channel.configureBlocking(false);
channel.write(ByteBuffer.wrap(new String("你在他乡还好吗").getBytes()));
channel.register(this.selector, SelectionKey.OP_READ);
} else if (key.isReadable()) {
read(key);
}
}
}
}
public void read(SelectionKey key) throws IOException{
SocketChannel channel = (SocketChannel) key.channel();
ByteBuffer buffer = ByteBuffer.allocate(1024);
int len = channel.read(buffer);
byte[] data = new byte[len];
System.arraycopy(buffer.array(), 0, data, 0, len);
String msg = new String(data).trim();
System.out.println("client receive one msg:"+msg);
ByteBuffer outBuffer = ByteBuffer.wrap(msg.getBytes());
}
public static void main(String[] args) throws IOException {
NIOClient client = new NIOClient();
client.initClient("localhost",8080);
client.listen();
}
}