我知道有几个类似的问题要么得到回答，要么仍然很突出，但对于我的生活......
稍后编辑2016-08-25 10:05 CST - 实际上，我问了错误的问题。
问题如下：鉴于我同时拥有一个netty服务器（取自DiscardServer示例）和一个netty客户端 - （见上文），我必须做些什么来强制DiscardServer立即向客户端发送请求？
我已将OutboundHandler添加到服务器和客户端。
在查看DiscardServer和PingPongServer示例后，会发生外部事件以启动所有操作。在丢弃服务器的情况下，它最初在等待telnet连接，然后将telnet msg中的任何内容传输到客户端。
对于PingPongServer， SERVER 正在等待客户端启动操作。
我想要的是服务器在与客户端连接后立即开始传输。 netty的所有例子都没有这样做。
如果我错过了某些东西，并且有人可以指出它，那就是很好的业力。
我的客户：
public final class P4Listener {
static final Logger LOG;
static final String HOST;
static final int PORT;
static final Boolean SSL = Boolean.FALSE;
public static Dto DTO;
static {
LOG = LoggerFactory.getLogger(P4Listener.class);
HOST = P4ListenerProperties.getP4ServerAddress();
PORT = Integer.valueOf(P4ListenerProperties.getListenerPort());
DTO = new Dto();
}
public static String getId() { return DTO.getId(); }
public static void main(String[] args) throws Exception {
final SslContext sslCtx;
if (SSL) {
LOG.info("{} creating SslContext", getId());
sslCtx = SslContextBuilder.forClient().trustManager(InsecureTrustManagerFactory.INSTANCE).build();
} else {
sslCtx = null;
}
EventLoopGroup group = new NioEventLoopGroup();
try {
Bootstrap b = new Bootstrap();
b.group(group).channel(NioSocketChannel.class)
.handler(new LoggingHandler(LogLevel.INFO))
.handler(new P4ListenerInitializer(sslCtx));
// Start the connection attempt.
LOG.debug(" {} starting connection attempt...", getId());
Channel ch = b.connect(HOST, PORT).sync().channel();
// ChannelFuture localWriteFuture = ch.writeAndFlush("ready\n");
// localWriteFuture.sync();
} finally {
group.shutdownGracefully();
}
}
}
public class P4ListenerHandler extends SimpleChannelInboundHandler<String> {
static final Logger LOG = LoggerFactory.getLogger(P4ListenerHandler.class);
static final DateTimeFormatter DTFormatter = DateTimeFormatter.ofPattern("yyyyMMdd-HHMMss.SSS");
static final String EndSOT;
static final String StartSOT;
static final String EOL = "\n";
static final ClassPathXmlApplicationContext AppContext;
static {
EndSOT = P4ListenerProperties.getEndSOT();
StartSOT = P4ListenerProperties.getStartSOT();
AppContext = new ClassPathXmlApplicationContext(new String[] { "applicationContext.xml" });
}
private final RequestValidator rv = new RequestValidator();
private JAXBContext jaxbContext = null;
private Unmarshaller jaxbUnmarshaller = null;
private boolean initialized = false;
private Dto dto;
public P4ListenerHandler() {
dto = new Dto();
}
public Dto getDto() { return dto; }
public String getId() { return getDto().getId(); }
Message convertXmlToMessage(String xml) {
if (xml == null)
throw new IllegalArgumentException("xml message is null!");
try {
jaxbContext = JAXBContext.newInstance(p4.model.xml.request.Message.class, p4.model.xml.request.Header.class,
p4.model.xml.request.Claims.class, p4.model.xml.request.Insurance.class,
p4.model.xml.request.Body.class, p4.model.xml.request.Prescriber.class,
p4.model.xml.request.PriorAuthorization.class,
p4.model.xml.request.PriorAuthorizationSupportingDocumentation.class);
jaxbUnmarshaller = jaxbContext.createUnmarshaller();
StringReader strReader = new StringReader(xml);
Message m = (Message) jaxbUnmarshaller.unmarshal(strReader);
return m;
} catch (JAXBException jaxbe) {
String error = StacktraceUtil.getCustomStackTrace(jaxbe);
LOG.error(error);
throw new P4XMLUnmarshalException("Problems when attempting to unmarshal transmission string: \n" + xml,
jaxbe);
}
}
@Override
public void channelActive(ChannelHandlerContext ctx) {
LOG.debug("{} let server know we are ready", getId());
ctx.writeAndFlush("Ready...\n");
}
/**
* Important - this method will be renamed to
* <code><b>messageReceived(ChannelHandlerContext, I)</b></code> in netty 5.0
*
* @param ctx
* @param msg
*/
@Override
protected void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception {
ChannelFuture lastWriteFuture = null;
LOG.debug("{} -- received message: {}", getId(), msg);
Channel channel = ctx.channel();
Message m = null;
try {
if (msg instanceof String && msg.length() > 0) {
m = convertXmlToMessage(msg);
m.setMessageStr(msg);
dto.setRequestMsg(m);
LOG.info("{}: received TIMESTAMP: {}", dto.getId(), LocalDateTime.now().format(DTFormatter));
LOG.debug("{}: received from server: {}", dto.getId(), msg);
/*
* theoretically we have a complete P4(XML) request
*/
final List<RequestFieldError> errorList = rv.validateMessage(m);
if (!errorList.isEmpty()) {
for (RequestFieldError fe : errorList) {
lastWriteFuture = channel.writeAndFlush(fe.toString().concat(EOL));
}
}
/*
* Create DBHandler with message, messageStr, clientIp to get
* dbResponse
*/
InetSocketAddress socketAddress = (InetSocketAddress) channel.remoteAddress();
InetAddress inetaddress = socketAddress.getAddress();
String clientIp = inetaddress.getHostAddress();
/*
* I know - bad form to ask the ApplicationContext for the
* bean... BUT ...lack of time turns angels into demons
*/
final P4DbRequestHandler dbHandler = (P4DbRequestHandler) AppContext.getBean("dbRequestHandler");
// must set the requestDTO for the dbHandler!
dbHandler.setClientIp(clientIp);
dbHandler.setRequestDTO(dto);
//
// build database request and receive response (string)
String dbResponse = dbHandler.submitDbRequest();
/*
* create ResponseHandler and get back response string
*/
P4ResponseHandler responseHandler = new P4ResponseHandler(dto, dbHandler);
String responseStr = responseHandler.decodeDbServiceResponse(dbResponse);
/*
* write response string to output and repeat exercise
*/
LOG.debug("{} -- response to be written back to server:\n {}", dto.getId(), responseStr);
lastWriteFuture = channel.writeAndFlush(responseStr.concat(EOL));
//
LOG.info("{}: response sent TIMESTAMP: {}", dto.getId(), LocalDateTime.now().format(DTFormatter));
} else {
throw new P4EventException(dto.getId() + " -- Message received is not a String");
}
processWriteFutures(lastWriteFuture);
} catch (Throwable t) {
String tError = StacktraceUtil.getCustomStackTrace(t);
LOG.error(tError);
} finally {
if (lastWriteFuture != null) {
lastWriteFuture.sync();
}
}
}
private void processWriteFutures(ChannelFuture writeFuture) throws InterruptedException {
// Wait until all messages are flushed before closing the channel.
if (writeFuture != null) {
writeFuture.sync();
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
cause.printStackTrace();
ctx.close();
}
}
/**
* Creates a newly configured {@link ChannelPipeline} for a new channel.
*/
public class P4ListenerInitializer extends ChannelInitializer<SocketChannel> {
private static final StringDecoder DECODER = new StringDecoder();
private static final StringEncoder ENCODER = new StringEncoder();
private final SslContext sslCtx;
public P4ListenerInitializer(SslContext sslCtx) {
this.sslCtx = sslCtx;
}
@Override
public void initChannel(SocketChannel ch) {
P4ListenerHandler lh = null;
ChannelPipeline pipeline = ch.pipeline();
if (sslCtx != null) {
P4Listener.LOG.info("{} -- constructing SslContext new handler ", P4Listener.getId());
pipeline.addLast(sslCtx.newHandler(ch.alloc(), P4Listener.HOST, P4Listener.PORT));
} else {
P4Listener.LOG.info("{} -- SslContext null; bypassing adding sslCtx.newHandler(ch.alloc(), P4Listener.HOST, P4Listener.PORT) ", P4Listener.getId());
}
// Add the text line codec combination first,
pipeline.addLast(new DelimiterBasedFrameDecoder(8192, Delimiters.lineDelimiter()));
pipeline.addLast(DECODER);
P4Listener.LOG.debug("{} -- added Decoder ", P4Listener.getId());
pipeline.addLast(ENCODER);
P4Listener.LOG.debug("{} -- added Encoder ", P4Listener.getId());
// and then business logic.
pipeline.addLast(lh = new P4ListenerHandler());
P4Listener.LOG.debug("{} -- added P4ListenerHandler: {} ", P4Listener.getId(), lh.getClass().getSimpleName());
}
}
@Sharable
public class P4ListenerOutboundHandler extends ChannelOutboundHandlerAdapter {
static final Logger LOG = LoggerFactory.getLogger(P4ListenerOutboundHandler.class);
private Dto outBoundDTO = new Dto();
public String getId() {return this.outBoundDTO.getId(); }
@Override
public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) {
try {
ChannelFuture lastWrite = ctx.write(Unpooled.copiedBuffer((String) msg, CharsetUtil.UTF_8));
try {
if (lastWrite != null) {
lastWrite.sync();
promise.setSuccess();
}
} catch (InterruptedException e) {
promise.setFailure(e);
e.printStackTrace();
}
} finally {
ReferenceCountUtil.release(msg);
}
}
}
答案 0 :(得分：0)
只需覆盖服务器处理程序上的channelActive(...)并在那里触发写入。
