Androidpn_server_筆記(一)

Androidpn_server筆記

隨便寫寫,可能有錯的地方

1. delivery tree的結構

能夠看出deliver對session的依賴很強,最後調用Connection的deliver方法進行信息的發送,實際上最下面用的是mina

信息的處理大約分爲兩種方式

[1]:接收客戶信息並做出響應(通常是在創建鏈接的時候),XMPPIoHandler的信息接收的回調函數中使用StanzaHandler中按照語法(Iq,Message,Presence)的類別進行分發到不一樣類別的路由(Router)-->(Handler)-->Session-->Connection.deliver

[2]:對已經創建鏈接的用戶進行消息的推送:NotificationManager.(sendBroadcast()|sendNotificationToUser())—>Session—>Connection.deliver

2. Session deliver的依賴使用

2.1. NotificationManager

2.1.1. sendBroadcast()

廣播函數:鏈接創建以後,發送推送消息的廣播接口

2.1.2. sendNotificationToUser()

單個用戶發送: 鏈接創建以後,根據用戶名稱進行推送的接口

2.1.3. createNotificationIQ

分析:

1. 該方法爲私有方法,那麼確定是爲了sendBroadcast和sendNotificationToUser兩個方法所設立

2. 返回的是smack包中的IQ,使用IQ語法來發送信息

下圖顯示了

IQ的set語法

自定義的命名空間NOTIFICATION,裏面包含了自定的封裝信息

數據包的截圖:

private IQ createNotificationIQ(String apiKey, String title,

String message, String uri) {

Random random = new Random();

String id = Integer.toHexString(random.nextInt());//使用隨機+hex的方法對id初始

// String id = String.valueOf(System.currentTimeMillis());

Element notification = DocumentHelper.createElement(QName.get(

"notification", NOTIFICATION_NAMESPACE));//讀取相應的namespace

notification.addElement("id").setText(id);

notification.addElement("apiKey").setText(apiKey);

notification.addElement("title").setText(title);

notification.addElement("message").setText(message);

notification.addElement("uri").setText(uri);

IQ iq = new IQ();

iq.setType(IQ.Type.set);

iq.setChildElement(notification);//包裝

return iq;

3. deliver的代碼概述

3.1. StanzaHandler(重點)

爲XmppIoHandler信息接收器的直接引用

Xml信息的直接接收入口

對象屬性 構造函數[可見實例化的StanzaHandler只爲一個Connection進行服務,此實例在session創建的時候進行初始化]

3.1.1. Process

核心入口方法

public void process(String stanza, XMPPPacketReader reader)

throws Exception {

boolean initialStream = stanza.startsWith("<stream:stream");//判斷是否爲初始化狀態

if (!sessionCreated || initialStream) {

if (!initialStream) {

return; // Ignore <?xml version="1.0"?>//若是session還未創建,而且initialStream並非初始化信息,直接棄掉

}

if (!sessionCreated) {//若是session還未創建,不論stream是否爲初始

sessionCreated = true;//是指session的標識符爲創建

MXParser parser = reader.getXPPParser();

parser.setInput(new StringReader(stanza));

createSession(parser);//創建session

} else if (startedTLS) {//若是session已經實例化,並且是xmpp的初始,判斷是否須要進行tls握手

startedTLS = false;

tlsNegotiated();//進行tls握手

}

return;

}

// If end of stream was requested

if (stanza.equals("</stream:stream>")) {//若是爲結尾stanza

session.close();//進行session的關閉操做

return;

}

// Ignore <?xml version="1.0"?>

if (stanza.startsWith("<?xml")) {

return;

}

// Create DOM object//這裏排除了上述的可能性

Element doc = reader.read(new StringReader(stanza)).getRootElement();//得到根doc

if (doc == null) {

return;

}

String tag = doc.getName();//得到元素的name

if ("starttls".equals(tag)) {//starttls關鍵字(重要)請求tls的通知節點

最後是利用Connection的startTLS(原理是在過濾器鏈的頭就加入過濾器(這裏用的是mina的基本方法))
 


if (negotiateTLS()) { // Negotiate TLS

startedTLS = true;

} else {//若是不成功,關閉鏈接

connection.close();

session = null;

}

} else if ("message".equals(tag)) {//message語法(按照圖示的樹形結構)

processMessage(doc);

} else if ("presence".equals(tag)) {//出席語法

log.debug("presence...");

processPresence(doc);

} else if ("iq".equals(tag)) {//iq語法

log.debug("iq...");

processIQ(doc);

} else {

log.warn("Unexpected packet tag (not message, iq, presence)"

+ doc.asXML());

session.close();

}

}

3.2. IQRouter

這個類把IQ packets分發到其相應的Handler之中

3.2.1. public void route(IQ packet)

此類的核心方法

public void route(IQ packet) {

if (packet == null) {

throw new NullPointerException();

}

JID sender = packet.getFrom();//獲取JID

ClientSession session = sessionManager.getSession(sender);

if (session == null

|| session.getStatus() == Session.STATUS_AUTHENTICATED

|| ("jabber:iq:auth".equals(packet.getChildElement()

.getNamespaceURI())

|| "jabber:iq:register".equals(packet.getChildElement()

.getNamespaceURI()) || "urn:ietf:params:xml:ns:xmpp-bind"

.equals(packet.getChildElement().getNamespaceURI()))) {

handle(packet);//在這裏掉用私有方法進行回覆

} else {//出現not_authorized 異常

IQ reply = IQ.createResultIQ(packet);//使用IQ自帶的create方法對result進行建造

reply.setChildElement(packet.getChildElement().createCopy());

reply.setError(PacketError.Condition.not_authorized);

session.process(reply);//直接包裝成error的回覆

}

}

3.2.2. private void handle(IQ packet)

由route調用的私有方法

private void handle(IQ packet) {

try {

Element childElement = packet.getChildElement();

String namespace = null;

if (childElement != null) {

namespace = childElement.getNamespaceURI();

}

if (namespace == null) {

if (packet.getType() != IQ.Type.result

&& packet.getType() != IQ.Type.error) {

log.warn("Unknown packet " + packet);

}

} else {

IQHandler handler = getHandler(namespace);//根據namespace獲得handler

if (handler == null) {

sendErrorPacket(packet,

PacketError.Condition.service_unavailable);

} else {

handler.process(packet); //進行操做

}

}

} catch (Exception e) {//處理中出現異常

log.error("Could not route packet", e);

Session session = sessionManager.getSession(packet.getFrom());

if (session != null) {

IQ reply = IQ.createResultIQ(packet);

reply.setError(PacketError.Condition.internal_server_error);

session.process(reply);

}

}

}

獲得handler的私有方法

private IQHandler getHandler(String namespace) {

IQHandler handler = namespace2Handlers.get(namespace);//在這裏調查namespace2Handler

if (handler == null) {

for (IQHandler handlerCandidate : iqHandlers) {

if (namespace.equalsIgnoreCase(handlerCandidate.getNamespace())) {

handler = handlerCandidate;

namespace2Handlers.put(namespace, handler);

break;

}

}

}

return handler;

}

public IQRouter() {

sessionManager = SessionManager.getInstance();

iqHandlers.add(new IQAuthHandler());

iqHandlers.add(new IQRegisterHandler());

iqHandlers.add(new IQRosterHandler());

}

從上面的代碼能夠看出所分配的Handler就是IQAuthHandler, IQRegisterHandler, IQRosterHandler利用handlerCandidate作的分類路由

3.3. PresenceRouter

出席路由:專門爲了Presence packet作分發的路由

public void route(Presence packet) {

if (packet == null) {

throw new NullPointerException();

}

ClientSession session = sessionManager.getSession(packet.getFrom());

if (session == null || session.getStatus() != Session.STATUS_CONNECTED) {

handle(packet);

} else {

packet.setTo(session.getAddress());

packet.setFrom((JID) null);

packet.setError(PacketError.Condition.not_authorized);

session.process(packet);

}

}

private void handle(Presence packet) {

try {

Presence.Type type = packet.getType();

// Presence updates (null == 'available')

if (type == null || Presence.Type.unavailable == type) {//不管是否可用交給handler進行操做

presenceUpdateHandler.process(packet);//在出席發送樹之中,只有presenceUpdateHandler,須要對presenceUpdateHandler進行分析

} else {

log.warn("Unknown presence type");

}

} catch (Exception e) {

log.error("Could not route packet", e);

Session session = sessionManager.getSession(packet.getFrom());

if (session != null) {

session.close();

}

}

}

PresenceUpdateHandler.process

public void process(Packet packet) {

ClientSession session = sessionManager.getSession(packet.getFrom());

try {

Presence presence = (Presence) packet;

Presence.Type type = presence.getType();

if (type == null) { // null == available

if (session != null

&& session.getStatus() == Session.STATUS_CLOSED) {

log.warn("Rejected available presence: " + presence + " - "

+ session);

return;

}

if (session != null) {

session.setPresence(presence);

if (!session.isInitialized()) {

// initSession(session);

session.setInitialized(true);

}

//添加離線發送

String username = null;

try {

username = session.getUsername();

} catch (UserNotFoundException e) {

log.error("User Not Found!");

}

if(username != null && session.getPresence().isAvailable()) {

(new NotificationManager()).pushCacheMessage(username);

}

}

} else if (Presence.Type.unavailable == type) {

if (session != null) {

session.setPresence(presence);

}

} else {

presence = presence.createCopy();

if (session != null) {

presence.setFrom(new JID(null, session.getServerName(),

null, true));

presence.setTo(session.getAddress());

} else {

JID sender = presence.getFrom();

presence.setFrom(presence.getTo());

presence.setTo(sender);

}

presence.setError(PacketError.Condition.bad_request);

PacketDeliverer.deliver(presence);

}

} catch (Exception e) {

log.error("Internal server error. Triggered by packet: " + packet,

e);

}

}