/**
* Serves the incoming connections.
*
* @throws IOException
* @throws DirectoryException
*/
private void serveIncomingConnections() throws IOException, DirectoryException {
int selectorState = selector.select();
// We can't rely on return value of select to determine if any keys
// are ready.
// see http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4850373
for (Iterator<SelectionKey> iterator = selector.selectedKeys().iterator();
iterator.hasNext(); ) {
SelectionKey key = iterator.next();
iterator.remove();
if (key.isAcceptable()) {
// Accept the new client connection.
ServerSocketChannel serverChannel = (ServerSocketChannel) key.channel();
SocketChannel clientChannel = serverChannel.accept();
if (clientChannel != null) {
acceptConnection(clientChannel);
}
}
if (selectorState == 0 && enabled && !shutdownRequested && logger.isTraceEnabled()) {
// Selected keys was non empty but select() returned 0.
// Log warning and hope it blocks on the next select() call.
logger.trace(
"Selector.select() returned 0. "
+ "Selected Keys: %d, Interest Ops: %d, Ready Ops: %d ",
selector.selectedKeys().size(), key.interestOps(), key.readyOps());
}
}
}
private void dispatch() throws IOException {
sel.select();
for (Iterator i = sel.selectedKeys().iterator(); i.hasNext(); ) {
SelectionKey sk = (SelectionKey) i.next();
i.remove();
Handler h = (Handler) sk.attachment();
h.handle(sk);
}
}
protected void handleClient(SelectionKey key) throws IOException {
SocketChannel sc = (SocketChannel) key.channel();
ClientInfo ci = (ClientInfo) allClients.get(sc);
if (ci == null) throw new IllegalStateException("Unknown client");
if (key.isWritable()) send(sc, ci);
if (key.isReadable())
// 从一个客户端读进所有的可用数据
recv(sc, ci);
}
static void test() throws Exception {
ServerSocketChannel ssc = null;
SocketChannel sc = null;
SocketChannel peer = null;
try {
ssc = ServerSocketChannel.open().bind(new InetSocketAddress(0));
// loopback connection
InetAddress lh = InetAddress.getLocalHost();
sc = SocketChannel.open(new InetSocketAddress(lh, ssc.socket().getLocalPort()));
peer = ssc.accept();
// peer sends message so that "sc" will be readable
int n = peer.write(ByteBuffer.wrap("Hello".getBytes()));
assert n > 0;
sc.configureBlocking(false);
Selector selector = Selector.open();
SelectionKey key = sc.register(selector, SelectionKey.OP_READ | SelectionKey.OP_WRITE);
boolean done = false;
int failCount = 0;
while (!done) {
int nSelected = selector.select();
if (nSelected > 0) {
if (nSelected > 1) throw new RuntimeException("More than one channel selected");
Set<SelectionKey> keys = selector.selectedKeys();
Iterator<SelectionKey> iterator = keys.iterator();
while (iterator.hasNext()) {
key = iterator.next();
iterator.remove();
if (key.isWritable()) {
failCount++;
if (failCount > 10) throw new RuntimeException("Test failed");
Thread.sleep(250);
}
if (key.isReadable()) {
done = true;
}
}
}
}
} finally {
if (peer != null) peer.close();
if (sc != null) sc.close();
if (ssc != null) ssc.close();
}
}
void processIO() {
Iterator<SelectionKey> it = mySelector.selectedKeys().iterator();
while (it.hasNext()) {
SelectionKey k = it.next();
it.remove();
if (k.isConnectable()) isConnectable(k);
else if (k.isAcceptable()) isAcceptable(k);
else {
if (k.isWritable()) isWritable(k);
if (k.isReadable()) isReadable(k);
}
}
}
void isReadable(SelectionKey k) {
EventableChannel ec = (EventableChannel) k.attachment();
long b = ec.getBinding();
if (ec.isWatchOnly()) {
if (ec.isNotifyReadable()) eventCallback(b, EM_CONNECTION_NOTIFY_READABLE, null);
} else {
myReadBuffer.clear();
try {
ec.readInboundData(myReadBuffer);
myReadBuffer.flip();
if (myReadBuffer.limit() > 0) {
if (ProxyConnections != null) {
EventableChannel target = ProxyConnections.get(b);
if (target != null) {
ByteBuffer myWriteBuffer = ByteBuffer.allocate(myReadBuffer.limit());
myWriteBuffer.put(myReadBuffer);
myWriteBuffer.flip();
target.scheduleOutboundData(myWriteBuffer);
} else {
eventCallback(b, EM_CONNECTION_READ, myReadBuffer);
}
} else {
eventCallback(b, EM_CONNECTION_READ, myReadBuffer);
}
}
} catch (IOException e) {
UnboundConnections.add(b);
}
}
}
public void run() {
try {
SocketChannel sc = SocketChannel.open();
InetSocketAddress sinaAddr = new InetSocketAddress("sina.com", 80);
sc.socket().connect(sinaAddr);
// init a selector via helper class selector provider
Selector aSel = SelectorProvider.provider().openSelector();
Socket soc = new Socket("host", 80);
soc.getChannel().register(aSel, SelectionKey.OP_ACCEPT);
// init a channel for server socket. method 1
ServerSocketChannel ssc = ServerSocketChannel.open();
ssc.configureBlocking(true);
// method 2, get server socket first, then init its channel
ServerSocket ss = new ServerSocket();
ServerSocketChannel ssc2 = ss.getChannel();
// set socket channel as non blocking.
ssc.configureBlocking(false);
InetSocketAddress isa = new InetSocketAddress("localhost", 9999);
ssc.socket().bind(isa);
SelectionKey acceptKey = ssc.register(aSel, SelectionKey.OP_ACCEPT);
int keysAdded = 0;
while ((keysAdded = aSel.select()) > 0) {
Set readyKeys = aSel.selectedKeys();
Iterator i = readyKeys.iterator();
while (i.hasNext()) {
SelectionKey sk = (SelectionKey) i.next();
i.remove();
ServerSocketChannel n = (ServerSocketChannel) sk.channel();
// now we got a new socket and its channel after accept in server
Socket s = n.accept().socket();
SocketChannel socketChannel = s.getChannel();
socketChannel.register(aSel, SelectionKey.OP_READ);
}
}
} catch (Exception e) {
}
}
/**
* Cleans up the contents of the selector, closing any server socket channels that might be
* associated with it. Any connections that might have been established through those channels
* should not be impacted.
*/
private void cleanUpSelector() {
try {
for (SelectionKey key : selector.keys()) {
try {
key.cancel();
} catch (Exception e) {
logger.traceException(e);
}
try {
key.channel().close();
} catch (Exception e) {
logger.traceException(e);
}
}
} catch (Exception e) {
logger.traceException(e);
}
}
void isConnectable(SelectionKey k) {
EventableSocketChannel ec = (EventableSocketChannel) k.attachment();
long b = ec.getBinding();
try {
if (ec.finishConnecting()) eventCallback(b, EM_CONNECTION_COMPLETED, null);
else UnboundConnections.add(b);
} catch (IOException e) {
UnboundConnections.add(b);
}
}
/** Selects on sockets and informs their Communicator when there is something to do. */
public void communicate(int timeout) {
try {
selector.select(timeout);
} catch (IOException e) {
// Not really sure why/when this happens yet
return;
}
Iterator<SelectionKey> keys = selector.selectedKeys().iterator();
while (keys.hasNext()) {
SelectionKey key = keys.next();
keys.remove();
if (!key.isValid()) continue; // WHY
Communicator communicator = (Communicator) key.attachment();
if (key.isReadable()) communicator.onReadable();
if (key.isWritable()) communicator.onWritable();
if (key.isAcceptable()) communicator.onAcceptable();
}
// Go through the queue and handle each communicator
while (!queue.isEmpty()) {
Communicator c = queue.poll();
c.onMemo();
}
}
void isAcceptable(SelectionKey k) {
ServerSocketChannel ss = (ServerSocketChannel) k.channel();
SocketChannel sn;
long b;
for (int n = 0; n < 10; n++) {
try {
sn = ss.accept();
if (sn == null) break;
} catch (IOException e) {
e.printStackTrace();
k.cancel();
ServerSocketChannel server = Acceptors.remove(k.attachment());
if (server != null)
try {
server.close();
} catch (IOException ex) {
}
;
break;
}
try {
sn.configureBlocking(false);
} catch (IOException e) {
e.printStackTrace();
continue;
}
b = createBinding();
EventableSocketChannel ec = new EventableSocketChannel(sn, b, mySelector);
Connections.put(b, ec);
NewConnections.add(b);
eventCallback(((Long) k.attachment()).longValue(), EM_CONNECTION_ACCEPTED, null, b);
}
}
void isWritable(SelectionKey k) {
EventableChannel ec = (EventableChannel) k.attachment();
long b = ec.getBinding();
if (ec.isWatchOnly()) {
if (ec.isNotifyWritable()) eventCallback(b, EM_CONNECTION_NOTIFY_WRITABLE, null);
} else {
try {
if (!ec.writeOutboundData()) UnboundConnections.add(b);
} catch (IOException e) {
UnboundConnections.add(b);
}
}
}
public void processSelectedKeys() throws IOException {
// 处理连接就绪事件
for (Iterator it = selector.selectedKeys().iterator(); it.hasNext(); ) {
SelectionKey selectionKey = (SelectionKey) it.next();
it.remove();
Target target = (Target) selectionKey.attachment();
SocketChannel socketChannel = (SocketChannel) selectionKey.channel();
try {
if (socketChannel.finishConnect()) {
selectionKey.cancel();
target.connectFinish = System.currentTimeMillis();
socketChannel.close();
addFinishedTarget(target);
}
} catch (IOException x) {
socketChannel.close();
target.failure = x;
addFinishedTarget(target);
}
}
}
void processSelectedKeys() throws IOException {
for (Iterator i = sel.selectedKeys().iterator(); i.hasNext(); ) {
SelectionKey sk = (SelectionKey) i.next();
i.remove();
Target t = (Target) sk.attachment();
SocketChannel sc = (SocketChannel) sk.channel();
try {
if (sc.finishConnect()) {
sk.cancel();
t.connectFinish = System.currentTimeMillis();
sc.close();
printer.add(t);
}
} catch (IOException x) {
sc.close();
t.failure = x;
printer.add(t);
}
}
}
void isReadable(SelectionKey k) {
EventableChannel ec = (EventableChannel) k.attachment();
long b = ec.getBinding();
if (ec.isWatchOnly()) {
if (ec.isNotifyReadable()) eventCallback(b, EM_CONNECTION_NOTIFY_READABLE, null);
} else {
myReadBuffer.clear();
try {
ec.readInboundData(myReadBuffer);
myReadBuffer.flip();
if (myReadBuffer.limit() > 0) eventCallback(b, EM_CONNECTION_READ, myReadBuffer);
} catch (IOException e) {
UnboundConnections.add(b);
}
}
}
private void readMessage(SelectionKey sk, SocketChannel readChannel, TcpAddress incomingAddress)
throws IOException {
// note that socket has been used
SocketEntry entry = (SocketEntry) sockets.get(incomingAddress);
if (entry != null) {
entry.used();
ByteBuffer readBuffer = entry.getReadBuffer();
if (readBuffer != null) {
readChannel.read(readBuffer);
if (readBuffer.hasRemaining()) {
readChannel.register(selector, SelectionKey.OP_READ, entry);
} else {
dispatchMessage(incomingAddress, readBuffer, readBuffer.capacity());
}
return;
}
}
ByteBuffer byteBuffer = ByteBuffer.wrap(buf);
byteBuffer.limit(messageLengthDecoder.getMinHeaderLength());
long bytesRead = readChannel.read(byteBuffer);
if (logger.isDebugEnabled()) {
logger.debug("Reading header " + bytesRead + " bytes from " + incomingAddress);
}
MessageLength messageLength = new MessageLength(0, Integer.MIN_VALUE);
if (bytesRead == messageLengthDecoder.getMinHeaderLength()) {
messageLength = messageLengthDecoder.getMessageLength(ByteBuffer.wrap(buf));
if (logger.isDebugEnabled()) {
logger.debug("Message length is " + messageLength);
}
if ((messageLength.getMessageLength() > getMaxInboundMessageSize())
|| (messageLength.getMessageLength() <= 0)) {
logger.error(
"Received message length "
+ messageLength
+ " is greater than inboundBufferSize "
+ getMaxInboundMessageSize());
synchronized (entry) {
entry.getSocket().close();
logger.info("Socket to " + entry.getPeerAddress() + " closed due to an error");
}
} else {
byteBuffer.limit(messageLength.getMessageLength());
bytesRead += readChannel.read(byteBuffer);
if (bytesRead == messageLength.getMessageLength()) {
dispatchMessage(incomingAddress, byteBuffer, bytesRead);
} else {
byte[] message = new byte[byteBuffer.limit()];
byteBuffer.flip();
byteBuffer.get(message, 0, byteBuffer.limit() - byteBuffer.remaining());
entry.setReadBuffer(ByteBuffer.wrap(message));
}
readChannel.register(selector, SelectionKey.OP_READ, entry);
}
} else if (bytesRead < 0) {
logger.debug("Socket closed remotely");
sk.cancel();
readChannel.close();
TransportStateEvent e =
new TransportStateEvent(
DefaultTcpTransportMapping.this,
incomingAddress,
TransportStateEvent.STATE_DISCONNECTED_REMOTELY,
null);
fireConnectionStateChanged(e);
}
}
public void run() {
// Here's where everything happens. The select method will
// return when any operations registered above have occurred, the
// thread has been interrupted, etc.
try {
while (!stop) {
try {
if (selector.select() > 0) {
if (stop) {
break;
}
// Someone is ready for I/O, get the ready keys
Set readyKeys = selector.selectedKeys();
Iterator it = readyKeys.iterator();
// Walk through the ready keys collection and process date requests.
while (it.hasNext()) {
SelectionKey sk = (SelectionKey) it.next();
it.remove();
SocketChannel readChannel = null;
TcpAddress incomingAddress = null;
if (sk.isAcceptable()) {
// The key indexes into the selector so you
// can retrieve the socket that's ready for I/O
ServerSocketChannel nextReady = (ServerSocketChannel) sk.channel();
// Accept the date request and send back the date string
Socket s = nextReady.accept().socket();
readChannel = s.getChannel();
readChannel.configureBlocking(false);
readChannel.register(selector, SelectionKey.OP_READ);
incomingAddress = new TcpAddress(s.getInetAddress(), s.getPort());
SocketEntry entry = new SocketEntry(incomingAddress, s);
sockets.put(incomingAddress, entry);
timeoutSocket(entry);
TransportStateEvent e =
new TransportStateEvent(
DefaultTcpTransportMapping.this,
incomingAddress,
TransportStateEvent.STATE_CONNECTED,
null);
fireConnectionStateChanged(e);
} else if (sk.isReadable()) {
readChannel = (SocketChannel) sk.channel();
incomingAddress =
new TcpAddress(
readChannel.socket().getInetAddress(), readChannel.socket().getPort());
} else if (sk.isWritable()) {
try {
SocketEntry entry = (SocketEntry) sk.attachment();
SocketChannel sc = (SocketChannel) sk.channel();
if (entry != null) {
writeMessage(entry, sc);
}
} catch (IOException iox) {
if (logger.isDebugEnabled()) {
iox.printStackTrace();
}
logger.warn(iox);
TransportStateEvent e =
new TransportStateEvent(
DefaultTcpTransportMapping.this,
incomingAddress,
TransportStateEvent.STATE_DISCONNECTED_REMOTELY,
iox);
fireConnectionStateChanged(e);
sk.cancel();
}
} else if (sk.isConnectable()) {
try {
SocketEntry entry = (SocketEntry) sk.attachment();
SocketChannel sc = (SocketChannel) sk.channel();
if ((!sc.isConnected()) && (sc.finishConnect())) {
sc.configureBlocking(false);
logger.debug("Connected to " + entry.getPeerAddress());
// make sure conncetion is closed if not used for timeout
// micro seconds
timeoutSocket(entry);
sc.register(selector, SelectionKey.OP_WRITE, entry);
}
TransportStateEvent e =
new TransportStateEvent(
DefaultTcpTransportMapping.this,
incomingAddress,
TransportStateEvent.STATE_CONNECTED,
null);
fireConnectionStateChanged(e);
} catch (IOException iox) {
if (logger.isDebugEnabled()) {
iox.printStackTrace();
}
logger.warn(iox);
sk.cancel();
}
}
if (readChannel != null) {
try {
readMessage(sk, readChannel, incomingAddress);
} catch (IOException iox) {
// IO exception -> channel closed remotely
if (logger.isDebugEnabled()) {
iox.printStackTrace();
}
logger.warn(iox);
sk.cancel();
readChannel.close();
TransportStateEvent e =
new TransportStateEvent(
DefaultTcpTransportMapping.this,
incomingAddress,
TransportStateEvent.STATE_DISCONNECTED_REMOTELY,
iox);
fireConnectionStateChanged(e);
}
}
}
}
} catch (NullPointerException npex) {
// There seems to happen a NullPointerException within the select()
npex.printStackTrace();
logger.warn("NullPointerException within select()?");
}
processPending();
}
if (ssc != null) {
ssc.close();
}
} catch (IOException iox) {
logger.error(iox);
lastError = iox;
}
if (!stop) {
stop = true;
synchronized (DefaultTcpTransportMapping.this) {
server = null;
}
}
}
/** returns a list of rdpserversockets */
Set<DatagramChannel> getActiveChannels() throws InterruptedException, java.io.IOException {
lock.lock();
try {
while (channelMap.isEmpty()) {
channelMapNotEmpty.await();
}
} finally {
lock.unlock();
}
Set<SelectionKey> readyKeys = null;
do {
lock.lock();
try {
if (!newChannelSet.isEmpty()) {
if (Log.loggingNet) Log.net("RDPServer.getActiveChannels: newChannelSet is not null");
Iterator<DatagramChannel> iter = newChannelSet.iterator();
while (iter.hasNext()) {
DatagramChannel newDC = iter.next();
iter.remove();
newDC.register(selector, SelectionKey.OP_READ);
}
}
} finally {
lock.unlock();
}
int numReady = selector.select(); // this is a blocking call - thread safe
selectCalls++;
if (numReady == 0) {
if (Log.loggingNet) Log.net("RDPServer.getActiveChannels: selector returned 0");
continue;
}
readyKeys = selector.selectedKeys();
if (Log.loggingNet)
Log.net(
"RDPServer.getActiveChannels: called select - # of ready keys = "
+ readyKeys.size()
+ " == "
+ numReady);
} while (readyKeys == null || readyKeys.isEmpty());
lock.lock();
try {
// get a datagramchannel that is ready
Set<DatagramChannel> activeChannels = new HashSet<DatagramChannel>();
Iterator<SelectionKey> iter = readyKeys.iterator();
while (iter.hasNext()) {
SelectionKey key = iter.next();
if (Log.loggingNet)
Log.net(
"RDPServer.getActiveChannels: matched selectionkey: "
+ key
+ ", isAcceptable="
+ key.isAcceptable()
+ ", isReadable="
+ key.isReadable()
+ ", isValid="
+ key.isValid()
+ ", isWritable="
+ key.isWritable());
iter.remove(); // remove from the selected key list
if (!key.isReadable() || !key.isValid()) {
Log.error(
"RDPServer.getActiveChannels: Throwing exception: RDPServer: not readable or invalid");
throw new MVRuntimeException("RDPServer: not readable or invalid");
}
DatagramChannel dc = (DatagramChannel) key.channel();
activeChannels.add(dc);
}
if (Log.loggingNet)
Log.net(
"RDPServer.getActiveChannels: returning " + activeChannels.size() + " active channels");
return activeChannels;
} finally {
lock.unlock();
}
}
public static void checkClients(List<SocketChannel> anonymousClients) {
try {
if (selector.selectNow() == 0) {
return;
}
Set<SelectionKey> keys = selector.selectedKeys();
for (SelectionKey key : keys) {
if ((key.readyOps() & SelectionKey.OP_ACCEPT) == SelectionKey.OP_ACCEPT) {
SocketChannel clientSocket = serverSocket.accept();
if (clientSocket == null) {
System.err.println("Error: can not accept");
continue;
}
anonymousClients.add(clientSocket);
clientSocket.configureBlocking(false);
clientSocket.register(selector, SelectionKey.OP_READ);
} else if ((key.readyOps() & SelectionKey.OP_READ) == SelectionKey.OP_READ) {
SocketChannel clientSocket = (SocketChannel) key.channel();
ByteBuffer bytes = ByteBuffer.allocate(4096);
if (clientSocket.read(bytes) != -1) {
byte[] message = bytes.array();
switch (message[0]) {
case 1:
{
String nick = MessageUtils.parseMessage(message).first;
if (!checkMessage(nick, "", clientSocket)) {
continue;
}
if (clients.containsKey(nick) || nick.length() > 32) {
if (nick.length() > 32) {
sendMessage(
clientSocket, MessageUtils.error("<server>: your nick is too long"));
} else {
sendMessage(
clientSocket,
MessageUtils.error("<server>: another user is using this nick"));
}
sendMessage(clientSocket, MessageUtils.bye());
anonymousClients.remove(clientSocket);
Utils.tryClose(clientSocket);
} else {
System.out.println(nick + " enter this chatroom");
notifyAllClients(nick + " enter this chatroom");
sendMessage(
clientSocket,
MessageUtils.message("<server>", "Wellcome, your nick is " + nick));
anonymousClients.remove(clientSocket);
clients.put(nick, clientSocket);
}
break;
}
case 2:
{
String nick = getNickFromSocket(clientSocket);
if (nick == null) {
Utils.printErrorAndExit("Error: it could not happen");
}
Utils.Pair<String, String> pair = MessageUtils.parseMessage(message);
if (!checkMessage(pair.first, pair.second, clientSocket)) {
continue;
}
if (!pair.first.equals(nick)) {
System.out.println("Cheater: " + nick);
sendMessage(clientSocket, MessageUtils.message("<server>", "do not cheat"));
}
for (Entry<String, SocketChannel> client : clients.entrySet()) {
if (!clientSocket.equals(client.getValue())) {
sendMessage(client.getValue(), MessageUtils.message(nick, pair.second));
}
}
break;
}
case 3:
disconnectClient(clientSocket);
break;
case 127:
{
String nick = getNickFromSocket(clientSocket);
Utils.Pair<String, String> pair = MessageUtils.parseMessage(message);
if (!checkMessage(pair.first, pair.second, clientSocket)) {
continue;
}
if (!pair.first.equals(nick)) {
System.out.println("Cheater: " + nick);
sendMessage(clientSocket, MessageUtils.message("<server>", "do not cheat"));
}
System.out.println(nick + ": " + pair.second);
break;
}
default:
System.out.println("Bad message from " + getNickFromSocket(clientSocket));
sendMessage(clientSocket, MessageUtils.message("<server>", "bad message"));
break;
}
} else {
disconnectClient(clientSocket);
}
}
}
keys.clear();
} catch (Exception expt) {
expt.printStackTrace();
Utils.printErrorAndExit(expt.getMessage());
}
}
private void go() throws IOException {
// Create a new selector
Selector selector = Selector.open();
// Open a listener on each port, and register each one
// with the selector
for (int i = 0; i < ports.length; ++i) {
ServerSocketChannel ssc = ServerSocketChannel.open();
ssc.configureBlocking(false);
ServerSocket ss = ssc.socket();
InetSocketAddress address = new InetSocketAddress(ports[i]);
ss.bind(address);
SelectionKey key = ssc.register(selector, SelectionKey.OP_ACCEPT);
System.out.println("Going to listen on " + ports[i]);
}
while (true) {
int num = selector.select();
Set selectedKeys = selector.selectedKeys();
Iterator it = selectedKeys.iterator();
while (it.hasNext()) {
SelectionKey key = (SelectionKey) it.next();
if ((key.readyOps() & SelectionKey.OP_ACCEPT) == SelectionKey.OP_ACCEPT) {
// Accept the new connection
ServerSocketChannel ssc = (ServerSocketChannel) key.channel();
SocketChannel sc = ssc.accept();
sc.configureBlocking(false);
// Add the new connection to the selector
SelectionKey newKey = sc.register(selector, SelectionKey.OP_READ);
it.remove();
System.out.println("Got connection from " + sc);
} else if ((key.readyOps() & SelectionKey.OP_READ) == SelectionKey.OP_READ) {
// Read the data
SocketChannel sc = (SocketChannel) key.channel();
// Echo data
int bytesEchoed = 0;
while (true) {
echoBuffer.clear();
int r = sc.read(echoBuffer);
if (r <= 0) {
break;
}
echoBuffer.flip();
sc.write(echoBuffer);
bytesEchoed += r;
}
System.out.println("Echoed " + bytesEchoed + " from " + sc);
it.remove();
}
}
// System.out.println( "going to clear" );
// selectedKeys.clear();
// System.out.println( "cleared" );
}
}
public void init() throws IOException {
this._logger = LoggerFactory.getLogger(AcquirePort.class);
selector = Selector.open();
// 通过open方法来打开一个未绑定的ServerSocketChannel实例
ServerSocketChannel server = ServerSocketChannel.open();
InetSocketAddress isa = new InetSocketAddress(_acquirePort);
// 将该ServerSocketChannel绑定到指定IP地址
server.socket().bind(isa);
// 设置ServerSocket以非阻塞方式工作
server.configureBlocking(false);
// 将server注册到指定Selector对象
server.register(selector, SelectionKey.OP_ACCEPT);
// 定义准备执行读取数据的ByteBuffer
ByteBuffer buff = ByteBuffer.allocate(1024);
while (selector.select() > 0) {
// 依次处理selector上的每个已选择的SelectionKey
Set<SelectionKey> sks = selector.selectedKeys();
Iterator keys = sks.iterator();
while (keys.hasNext()) {
SelectionKey sk = (SelectionKey) keys.next();
// 从selector上的已选择Key集中删除正在处理的SelectionKey
keys.remove();
// 如果sk对应的通道包含客户端的连接请求
if (sk.isAcceptable()) {
// 调用accept方法接受连接，产生服务器端对应的SocketChannel
SocketChannel sc = server.accept();
// 设置采用非阻塞模式
sc.configureBlocking(false);
// 将该SocketChannel也注册到selector
sc.register(selector, SelectionKey.OP_READ);
}
// 如果sk对应的通道有数据需要读取
if (sk.isReadable()) {
// 获取该SelectionKey对应的Channel，该Channel中有可读的数据
SocketChannel sc = (SocketChannel) sk.channel();
// 开始读取数据
try {
while (sc.read(buff) > 0) {
buff.flip();
this._logger.info("content" + buff);
sc.write(buff);
if (buff.hasRemaining()) {
buff.compact();
} else {
buff.clear();
}
}
// 打印从该sk对应的Channel里读取到的数据
this._logger.info("accpect content" + buff);
}
// 如果捕捉到该sk对应的Channel出现了异常，即表明该Channel
// 对应的Client出现了问题，所以从Selector中取消sk的注册
catch (IOException ex) {
// 从Selector中删除指定的SelectionKey
sk.cancel();
if (sk.channel() != null) {
sk.channel().close();
}
}
}
}
}
}