一.udp创建服务端
/**
* udp 服务器
*/
@Slf4j
@Component
public class UdpServer {
/**
* 创建服务端
*/
@Async
public void bind(int port) {
EventLoopGroup group = new NioEventLoopGroup();
try {
Bootstrap b = new Bootstrap();
b.group(group)
.channel(NioDatagramChannel.class)
.option(ChannelOption.SO_BROADCAST, true)
.option(ChannelOption.RCVBUF_ALLOCATOR, new FixedRecvByteBufAllocator(65535))
.handler(new ChannelInitializer<DatagramChannel>() {
@Override
public void initChannel(DatagramChannel ch) {
ChannelPipeline cp = ch.pipeline();
cp.addLast(new ServerHandler(port));
}
});
Channel serverChannel = b.bind(port).sync().channel();
log.info("UdpServer start success...");
serverChannel.closeFuture().await();
} catch (Exception e) {
log.error("UdpServer start fall！");
} finally {
group.shutdownGracefully();
}
}
private class ServerHandler extends SimpleChannelInboundHandler<DatagramPacket> {
private int port;// 当前 端口
public ServerHandler(int port) {
this.port = port;
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
log.error(cause.getMessage());
cause.printStackTrace();
}
/**
* 接收消息
*/
@Override
protected void channelRead0(ChannelHandlerContext ctx, DatagramPacket packet) {
// 1.获取数据内容，它是一个ByteBuf
ByteBuf content = packet.content();
String request = content.toString(CharsetUtil.UTF_8);
// 2.你可以使用ByteBuf的API来读取数据
//byte[] bytes = new byte[content.readableBytes()];
//content.readBytes(bytes);
//String request = new String(bytes, StandardCharsets.UTF_8);
InetSocketAddress senderAddress = packet.sender();
log.info("{} ---> {}:{}", senderAddress.getAddress().getHostAddress(), this.port, request);
}
}
}
二.udp创建客户端
下面展示一些 有些地方赖得改了，当是记录。
@Slf4j
@Component
public class UdpClient {
/**
* 发送udp，等待对方回复
*
* @param ip
* @param port
* @param format str,hex
* @param msg
* @return
*/
public String sendData(String ip, int port, String format, Object msg) {
ScheduledExecutorService executorService = Executors.newScheduledThreadPool(1);
EventLoopGroup group = new NioEventLoopGroup();
Channel channel = null;
Response r = new Response();
try {
InetSocketAddress inetSocketAddress = new InetSocketAddress(InetAddress.getByName(ip), port);
Bootstrap b = new Bootstrap();
b.group(group)
.channel(NioDatagramChannel.class)
.handler(new SimpleChannelInboundHandler() {
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
log.error("exceptionCaught ->" + cause.getMessage());
cause.printStackTrace();
ctx.close();
}
@Override
protected void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception {
// 处理接收到的数据
ByteBuf byteBuf = ((DatagramPacket)msg).content();
String response = null;
if (format.equals("str")) {
response = byteBuf.toString(StandardCharsets.UTF_8);
} else {
response = ByteBufUtil.hexDump(byteBuf);
}
log.info("response msg: " + response);
r.setMsg(response);
ctx.close();
}
});
ChannelFuture future = b.bind(0).sync(); // 绑定端口0以获取随机可用端口
channel = future.channel();
log.info("{} <- {}", ip, msg.toString());
Channel finalChannel = channel;
Future<?> executorServiceFuture = executorService.schedule(() -> {
// 检查Channel是否仍然是活动状态
if (finalChannel.isActive()) {
finalChannel.close();
}
}, 35, TimeUnit.SECONDS);
ByteBuf byteBuf = null;
if (format.equals("str")) {
byteBuf = Unpooled.copiedBuffer(msg.toString(), CharsetUtil.UTF_8); // 将消息内容转换为ByteBuf
} else {
byte[] bytes = hexString2Bytes(msg.toString());// 将16进制字符串转换为字节数组
byteBuf = Unpooled.wrappedBuffer(bytes); // 使用字节数组创建ByteBuf
}
DatagramPacket requestPacket = new DatagramPacket(byteBuf, inetSocketAddress);
channel.writeAndFlush(requestPacket);// 发送
channel.closeFuture().await();//异步等待，通道关闭后会往下执行
executorServiceFuture.cancel(true); // 立刻中断
return r.getMsg();
} catch (Exception e) {
e.printStackTrace();
return null;
} finally {
executorService.shutdown(); // 清理资源
if (channel != null) channel.close();
group.shutdownGracefully();
}
}
/**
* 发送udp，不等待回复
* @param ip
* @param port
* @param msg
*/
public void sendDataNoReply(String ip, int port, Object msg) {
EventLoopGroup group = new NioEventLoopGroup();
try {
Bootstrap bootstrap = new Bootstrap();
bootstrap.group(group)
.channel(NioDatagramChannel.class)
.option(ChannelOption.SO_BROADCAST, true)
.handler(new SimpleChannelInboundHandler() {
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
cause.printStackTrace();
ctx.close();
}
@Override
protected void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception {
// 处理接收到的数据
}
});
Channel channel = bootstrap.bind(0).sync().channel();
// 发送数据到指定的地址和端口
InetSocketAddress address = new InetSocketAddress(ip, port);
ByteBuf buffer = Unpooled.copiedBuffer(msg.toString(), CharsetUtil.UTF_8);
DatagramPacket packet = new DatagramPacket(buffer, address);
channel.writeAndFlush(packet);
// 等待一段时间以确保数据发送完成
//Thread.sleep(1000);
} catch (InterruptedException e) {
log.error("发送udp数据失败:", e);
throw new RuntimeException("发送数据失败或连接不上");
} finally {
group.shutdownGracefully();
}
}
class Response {
private String msg;
public Response() {
}
public String getMsg() {
return msg;
}
public void setMsg(String msg) {
this.msg = msg;
}
}
public static byte[] hexString2Bytes(String src) {
byte[] bytes = new byte[src.length() / 2];
for (int i = 0; i < bytes.length; i++) {
int index = i * 2;
int j = Integer.parseInt(src.substring(index, index + 2), 16);
bytes[i] = (byte) j;
}
return bytes;
}
}