我正在写一个NIO服务器，现在正在测试我正在连接到我自己，我把它写到客户端发送握手协议的地方，服务器必须响应但是当我尝试读取握手时我得到的是即使有数据等待读取，字节缓冲区中的空字节也是如此。我已附上下面的协议代码
public class HooMENodeProtocol implements TCPProtocol {
private int bufSize; // Size of I/O buffer
/**
* initializes buffer size
* @param bufSize the size of the byte buffer
*/
public HooMENodeProtocol(int bufSize) {
this.bufSize = bufSize;
}
/**
* accepts incoming network connections
*/
public void handleAccept(SelectionKey key) throws IOException {
SocketChannel clntChan = ((ServerSocketChannel) key.channel()).accept();
clntChan.configureBlocking(false); // Must be nonblocking to register
// Register the selector with new channel for read and attach byte buffer
clntChan.register(key.selector(), SelectionKey.OP_READ, new HooMEAttachment(ByteBuffer.allocate(bufSize),
new LinkedBlockingQueue<HooMEMessage>(Consts.SEND_QUEUE_CAPACITY), false));
}
/**
* handles read connections for channels
*/
public void handleRead(SelectionKey key) throws IOException {
// Client socket channel has pending data
SocketChannel clntChan = (SocketChannel) key.channel();
ByteBuffer buf = ((HooMEAttachment) key.attachment()).getBuffer();
buf.flip();
long bytesRead = clntChan.read(buf);
if (bytesRead == -1) { // Did the other end close?
clntChan.close();
} else if (bytesRead > 0 && !HooMEUtilities.isEmpty(buf.array())) {
System.out.println(Arrays.toString(buf.array()));
InputStream anInputStream = new ByteArrayInputStream (buf.array());
MessageInput anInput = new MessageInput (anInputStream);
//if we are supposed to receive a handshake
if(!((HooMEAttachment)key.attachment()).getSendHandshake()&&!((HooMEAttachment)key.attachment()).connectionOk()) {
String greeting = null;
try {
System.out.println("got a handshake");
greeting = anInput.readString();
anInput.readString();
} //consume the second new line character
catch (BadAttributeValueException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if(greeting.equals(Consts.HANDSHAKE_GREETING)) {
key.interestOps(SelectionKey.OP_WRITE);
} else {
//handshake greeting was wrong we will terminate this connection
key.channel().close();
key.cancel();
}
// if we are supposed to be reading an acknowledgment
} else if( ((HooMEAttachment)key.attachment()).getSendHandshake() && !((HooMEAttachment)key.attachment()).connectionOk()) {
String response = null;
try {
response = anInput.readString();
if(response.equals(Consts.HANDSHAKE_RESPONSE)) {
((HooMEAttachment)key.attachment()).setConnectionOk(true);
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
anInput.readString(); //consume the second newline character
} else {
key.channel().close();
key.cancel();
}
} catch (BadAttributeValueException e) {
e.printStackTrace();
}
} else {
HooMEMessage aMessage= null;
try {
aMessage = HooMEMessage.decode(anInput);
//if we have a response sent back
if(aMessage instanceof HooMEResponse || aMessage.getTtl()>0) { //treat all responses as comcast
//look up id of message in the forwarding table
for (Entry<byte[], InetAddress> entry : HooMENode.mappingTable.entrySet()) {
if(Arrays.equals(aMessage.getId(), entry.getKey())) { //if we have a mapping for this id in our routing table
//loop through our neighbours and find the one we want
for(SelectionKey aKey:key.selector().keys()) {
if(aKey.channel() instanceof SocketChannel &&
((SocketChannel)aKey.channel()).socket().getInetAddress()==entry.getValue()) {
aMessage.setTtl(aMessage.getTtl()-1);
((HooMEAttachment)key.attachment()).getSendQueue().add(aMessage);
break;
}
}
}
}
} else if (aMessage instanceof HooMESearch) { //if a search message has been sent .
//broadcast service requested broadcast the search to all and sundry
if(aMessage.getRoutingService().getServiceCode()==0 &&aMessage.getTtl()>0) {
aMessage.setTtl(aMessage.getTtl()-1);
for(SelectionKey aKey:key.selector().keys()) {
if(aKey.attachment()!=null && aKey.attachment() instanceof HooMEAttachment) {
((HooMEAttachment)aKey.attachment()).getSendQueue().add(aMessage);
}
}
//place mapping for the broadcast message in the mapping table
HooMENode.mappingTable.put(aMessage.getId(), ((SocketChannel)key.channel()).socket().getInetAddress());
}
//respond to the search
List<Result> searchResults = HooMENode.getFileResults(((HooMESearch)aMessage).getSearchString());
HooMEMessage response = new HooMEResponse(aMessage.getId(), 1, RoutingService.getRoutingService(1), aMessage.getDestinationHooMEAddress(), aMessage.getSourceHooMEAddress(),
new InetSocketAddress(HooMENode.address,HooMENode.downloadPort));
((HooMEResponse)response).getResultList().addAll(searchResults);
((HooMEAttachment)key.attachment()).getSendQueue().add(response);
}
// Indicate via key that reading/writing are both of interest now.
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}catch (IOException e) {
e.printStackTrace();
} catch (BadAttributeValueException e) {
System.out.println(e.getMessage());
}
}
}
}
/**
* handles write connections for channels
*/
public void handleWrite(SelectionKey key) throws IOException {
OutputStream anOutput = new ByteArrayOutputStream();
ByteBuffer buf = ((HooMEAttachment) key.attachment()).getBuffer();
/*
* Channel is available for writing, and key is valid (i.e., client channel
* not closed).
*/
//we are supposed to send an acknowledgement of a handshake
if(!((HooMEAttachment)key.attachment()).getSendHandshake()&&!((HooMEAttachment)key.attachment()).connectionOk()) {
anOutput.write((Consts.HANDSHAKE_RESPONSE+Consts.EOLN+Consts.EOLN).getBytes(HooMEMessage.CHARENCODING));
//confirm that the connection is ok
((HooMEAttachment)key.attachment()).setConnectionOk(true);
buf.put(((ByteArrayOutputStream)anOutput).toByteArray());
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
System.out.println(Arrays.toString(buf.array()));
if(!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}
//if we are supposed to be sending an handshake
} else if( ((HooMEAttachment)key.attachment()).getSendHandshake() && !((HooMEAttachment)key.attachment()).connectionOk()) {
anOutput.write((Consts.HANDSHAKE_GREETING+Consts.EOLN+Consts.EOLN).getBytes(HooMEMessage.CHARENCODING));
buf.put(((ByteArrayOutputStream)anOutput).toByteArray());
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
System.out.println(Arrays.toString(buf.array()));
if(!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ);
}
} else {
//check the send queue for messages that can be sent if there are none then do nothing
HooMEMessage aMessage = ((HooMEAttachment) key.attachment()).getSendQueue().poll();
if(aMessage != null) {
MessageOutput aMessageOutput = new MessageOutput(anOutput);
aMessage.encode(aMessageOutput);
}
buf.put(((ByteArrayOutputStream)anOutput).toByteArray());
SocketChannel clntChan = (SocketChannel) key.channel();
clntChan.write(buf);
System.out.println(Arrays.toString(buf.array()));
if(!buf.hasRemaining()) {
key.interestOps(SelectionKey.OP_READ | SelectionKey.OP_WRITE);
}
}
// Make room for more data to be read in
}
}
答案 0 :(得分：0)
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