ZooKeeper.class
1 public String create(final String path, byte data[], List<ACL> acl,
2 CreateMode createMode)
3 throws KeeperException, InterruptedException
4 {
5 final String clientPath = path;
6 PathUtils.validatePath(clientPath, createMode.isSequential());
7
8 final String serverPath = prependChroot(clientPath);
9
10 RequestHeader h = new RequestHeader();
11 h.setType(ZooDefs.OpCode.create);
12 CreateRequest request = new CreateRequest();
13 CreateResponse response = new CreateResponse();
14 request.setData(data);
15 request.setFlags(createMode.toFlag());
16 request.setPath(serverPath);
17 if (acl != null && acl.size() == 0) {
18 throw new KeeperException.InvalidACLException();
19 }
20 request.setAcl(acl);
21 ReplyHeader r = cnxn.submitRequest(h, request, response, null);
22 if (r.getErr() != 0) {
23 throw KeeperException.create(KeeperException.Code.get(r.getErr()),
24 clientPath);
25 }
26 if (cnxn.chrootPath == null) {
27 return response.getPath();
28 } else {
29 return response.getPath().substring(cnxn.chrootPath.length());
30 }
31 }
ClientCnxn.class, 放到队列中,循环等到packet标识位finished。
1 public ReplyHeader submitRequest(RequestHeader h, Record request,
2 Record response, WatchRegistration watchRegistration)
3 throws InterruptedException {
4 ReplyHeader r = new ReplyHeader();
5 Packet packet = queuePacket(h, r, request, response, null, null, null,
6 null, watchRegistration);
7 synchronized (packet) {
8 while (!packet.finished) {
9 packet.wait();
10 }
11 }
12 return r;
13 }
1 Packet queuePacket(RequestHeader h, ReplyHeader r, Record request,
2 Record response, AsyncCallback cb, String clientPath,
3 String serverPath, Object ctx, WatchRegistration watchRegistration)
4 {
5 Packet packet = null;
6
7 // Note that we do not generate the Xid for the packet yet. It is
8 // generated later at send-time, by an implementation of ClientCnxnSocket::doIO(),
9 // where the packet is actually sent.
10 synchronized (outgoingQueue) {
11 packet = new Packet(h, r, request, response, watchRegistration);
12 packet.cb = cb;
13 packet.ctx = ctx;
14 packet.clientPath = clientPath;
15 packet.serverPath = serverPath;
16 if (!state.isAlive() || closing) {
17 conLossPacket(packet);
18 } else {
19 // If the client is asking to close the session then
20 // mark as closing
21 if (h.getType() == OpCode.closeSession) {
22 closing = true;
23 }
24 outgoingQueue.add(packet);
25 }
26 }
27 sendThread.getClientCnxnSocket().wakeupCnxn();
28 return packet;
29 }
ClientCnxnSocket.class
1 @Override
2 void doTransport(int waitTimeOut, List<Packet> pendingQueue, LinkedList<Packet> outgoingQueue,
3 ClientCnxn cnxn)
4 throws IOException, InterruptedException {
5 selector.select(waitTimeOut);
6 Set<SelectionKey> selected;
7 synchronized (this) {
8 selected = selector.selectedKeys();
9 }
10 // Everything below and until we get back to the select is
11 // non blocking, so time is effectively a constant. That is
12 // Why we just have to do this once, here
13 updateNow();
14 for (SelectionKey k : selected) {
15 SocketChannel sc = ((SocketChannel) k.channel());
16 if ((k.readyOps() & SelectionKey.OP_CONNECT) != 0) {
17 if (sc.finishConnect()) {
18 updateLastSendAndHeard();
19 sendThread.primeConnection();
20 }
21 } else if ((k.readyOps() & (SelectionKey.OP_READ | SelectionKey.OP_WRITE)) != 0) {
22 doIO(pendingQueue, outgoingQueue, cnxn);
23 }
24 }
25 if (sendThread.getZkState().isConnected()) {
26 synchronized(outgoingQueue) {
27 if (findSendablePacket(outgoingQueue,
28 cnxn.sendThread.clientTunneledAuthenticationInProgress()) != null) {
29 enableWrite();
30 }
31 }
32 }
33 selected.clear();
34 }
1 void doIO(List<Packet> pendingQueue, LinkedList<Packet> outgoingQueue, ClientCnxn cnxn)
2 throws InterruptedException, IOException {
3 SocketChannel sock = (SocketChannel) sockKey.channel();
4 if (sock == null) {
5 throw new IOException("Socket is null!");
6 }
7 if (sockKey.isReadable()) {
8 int rc = sock.read(incomingBuffer);
9 if (rc < 0) {
10 throw new EndOfStreamException(
11 "Unable to read additional data from server sessionid 0x"
12 + Long.toHexString(sessionId)
13 + ", likely server has closed socket");
14 }
15 if (!incomingBuffer.hasRemaining()) {
16 incomingBuffer.flip();
17 if (incomingBuffer == lenBuffer) {
18 recvCount++;
19 readLength();
20 } else if (!initialized) {
21 readConnectResult();
22 enableRead();
23 if (findSendablePacket(outgoingQueue,
24 cnxn.sendThread.clientTunneledAuthenticationInProgress()) != null) {
25 // Since SASL authentication has completed (if client is configured to do so),
26 // outgoing packets waiting in the outgoingQueue can now be sent.
27 enableWrite();
28 }
29 lenBuffer.clear();
30 incomingBuffer = lenBuffer;
31 updateLastHeard();
32 initialized = true;
33 } else {
34 sendThread.readResponse(incomingBuffer);
35 lenBuffer.clear();
36 incomingBuffer = lenBuffer;
37 updateLastHeard();
38 }
39 }
40 }
41 if (sockKey.isWritable()) {
42 synchronized(outgoingQueue) {
43 Packet p = findSendablePacket(outgoingQueue,
44 cnxn.sendThread.clientTunneledAuthenticationInProgress());
45
46 if (p != null) {
47 updateLastSend();
48 // If we already started writing p, p.bb will already exist
49 if (p.bb == null) {
50 if ((p.requestHeader != null) &&
51 (p.requestHeader.getType() != OpCode.ping) &&
52 (p.requestHeader.getType() != OpCode.auth)) {
53 p.requestHeader.setXid(cnxn.getXid());
54 }
55 p.createBB();
56 }
57 sock.write(p.bb);
58 if (!p.bb.hasRemaining()) {
59 sentCount++;
60 outgoingQueue.removeFirstOccurrence(p);
61 if (p.requestHeader != null
62 && p.requestHeader.getType() != OpCode.ping
63 && p.requestHeader.getType() != OpCode.auth) {
64 synchronized (pendingQueue) {
65 pendingQueue.add(p);
66 }
67 }
68 }
69 }
70 if (outgoingQueue.isEmpty()) {
71 // No more packets to send: turn off write interest flag.
72 // Will be turned on later by a later call to enableWrite(),
73 // from within ZooKeeperSaslClient (if client is configured
74 // to attempt SASL authentication), or in either doIO() or
75 // in doTransport() if not.
76 disableWrite();
77 } else if (!initialized && p != null && !p.bb.hasRemaining()) {
78 // On initial connection, write the complete connect request
79 // packet, but then disable further writes until after
80 // receiving a successful connection response. If the
81 // session is expired, then the server sends the expiration
82 // response and immediately closes its end of the socket. If
83 // the client is simultaneously writing on its end, then the
84 // TCP stack may choose to abort with RST, in which case the
85 // client would never receive the session expired event. See
86 // http://docs.oracle.com/javase/6/docs/technotes/guides/net/articles/connection_release.html
87 disableWrite();
88 } else {
89 // Just in case
90 enableWrite();
91 }
92 }
93 }
94 }
SendThread.class
1 void readResponse(ByteBuffer incomingBuffer) throws IOException {
2 ByteBufferInputStream bbis = new ByteBufferInputStream(
3 incomingBuffer);
4 BinaryInputArchive bbia = BinaryInputArchive.getArchive(bbis);
5 ReplyHeader replyHdr = new ReplyHeader();
6
7 replyHdr.deserialize(bbia, "header");
8 if (replyHdr.getXid() == -2) {
9 // -2 is the xid for pings
10 if (LOG.isDebugEnabled()) {
11 LOG.debug("Got ping response for sessionid: 0x"
12 + Long.toHexString(sessionId)
13 + " after "
14 + ((System.nanoTime() - lastPingSentNs) / 1000000)
15 + "ms");
16 }
17 return;
18 }
19 if (replyHdr.getXid() == -4) {
20 // -4 is the xid for AuthPacket
21 if(replyHdr.getErr() == KeeperException.Code.AUTHFAILED.intValue()) {
22 state = States.AUTH_FAILED;
23 eventThread.queueEvent( new WatchedEvent(Watcher.Event.EventType.None,
24 Watcher.Event.KeeperState.AuthFailed, null) );
25 }
26 if (LOG.isDebugEnabled()) {
27 LOG.debug("Got auth sessionid:0x"
28 + Long.toHexString(sessionId));
29 }
30 return;
31 }
32 if (replyHdr.getXid() == -1) {
33 // -1 means notification
34 if (LOG.isDebugEnabled()) {
35 LOG.debug("Got notification sessionid:0x"
36 + Long.toHexString(sessionId));
37 }
38 WatcherEvent event = new WatcherEvent();
39 event.deserialize(bbia, "response");
40
41 // convert from a server path to a client path
42 if (chrootPath != null) {
43 String serverPath = event.getPath();
44 if(serverPath.compareTo(chrootPath)==0)
45 event.setPath("/");
46 else if (serverPath.length() > chrootPath.length())
47 event.setPath(serverPath.substring(chrootPath.length()));
48 else {
49 LOG.warn("Got server path " + event.getPath()
50 + " which is too short for chroot path "
51 + chrootPath);
52 }
53 }
54
55 WatchedEvent we = new WatchedEvent(event);
56 if (LOG.isDebugEnabled()) {
57 LOG.debug("Got " + we + " for sessionid 0x"
58 + Long.toHexString(sessionId));
59 }
60
61 eventThread.queueEvent( we );
62 return;
63 }
64
65 // If SASL authentication is currently in progress, construct and
66 // send a response packet immediately, rather than queuing a
67 // response as with other packets.
68 if (clientTunneledAuthenticationInProgress()) {
69 GetSASLRequest request = new GetSASLRequest();
70 request.deserialize(bbia,"token");
71 zooKeeperSaslClient.respondToServer(request.getToken(),
72 ClientCnxn.this);
73 return;
74 }
75
76 Packet packet;
77 synchronized (pendingQueue) {
78 if (pendingQueue.size() == 0) {
79 throw new IOException("Nothing in the queue, but got "
80 + replyHdr.getXid());
81 }
82 packet = pendingQueue.remove();
83 }
84 /*
85 * Since requests are processed in order, we better get a response
86 * to the first request!
87 */
88 try {
89 if (packet.requestHeader.getXid() != replyHdr.getXid()) {
90 packet.replyHeader.setErr(
91 KeeperException.Code.CONNECTIONLOSS.intValue());
92 throw new IOException("Xid out of order. Got Xid "
93 + replyHdr.getXid() + " with err " +
94 + replyHdr.getErr() +
95 " expected Xid "
96 + packet.requestHeader.getXid()
97 + " for a packet with details: "
98 + packet );
99 }
100
101 packet.replyHeader.setXid(replyHdr.getXid());
102 packet.replyHeader.setErr(replyHdr.getErr());
103 packet.replyHeader.setZxid(replyHdr.getZxid());
104 if (replyHdr.getZxid() > 0) {
105 lastZxid = replyHdr.getZxid();
106 }
107 if (packet.response != null && replyHdr.getErr() == 0) {
108 packet.response.deserialize(bbia, "response");
109 }
110
111 if (LOG.isDebugEnabled()) {
112 LOG.debug("Reading reply sessionid:0x"
113 + Long.toHexString(sessionId) + ", packet:: " + packet);
114 }
115 } finally {
116 finishPacket(packet);
117 }
118 }