合肥小程序开发,优质的seo快速排名优化,睢宁做网站,关于建设网站的情况说明书最近要弄一个消息推送的功能#xff0c;在网上找了很多的关于pushlet的文章#xff0c;虽然写的都很详细#xff0c;但是本人看了以后却总觉得是模棱两可不知道如何下手#xff0c;最终参考了这些文章中的一些内容#xff0c;并结合官网的源代码#xff0c;做了自己的修改… 最近要弄一个消息推送的功能在网上找了很多的关于pushlet的文章虽然写的都很详细但是本人看了以后却总觉得是模棱两可···不知道如何下手最终参考了这些文章中的一些内容并结合官网的源代码做了自己的修改。 第一部分 修改的地方 首先修改了nl.justobjects.pushlet.core.Session增加了even字段增加了getEvent方法同时修改了create方法修改如下 // Copyright (c) 2000 Just Objects B.V. justjustobjects.nl
// Distributable under LGPL license. See terms of license at gnu.org.package nl.justobjects.pushlet.core;import nl.justobjects.pushlet.util.Log;
import nl.justobjects.pushlet.util.PushletException;/*** Represents client pushlet session state.** author Just van den Broecke - Just Objects copy;* version $Id: Session.java,v 1.8 2007/11/23 14:33:07 justb Exp $*/
public class Session implements Protocol, ConfigDefs {private Controller controller;private Subscriber subscriber;/** 增加了even字段 */private Event event;private String userAgent;private long LEASE_TIME_MILLIS Config.getLongProperty(SESSION_TIMEOUT_MINS) * 60 * 1000;private volatile long timeToLive LEASE_TIME_MILLIS;public static String[] FORCED_PULL_AGENTS Config.getProperty(LISTEN_FORCE_PULL_AGENTS).split(,);private String address unknown;private String format FORMAT_XML;private String id;/*** Protected constructor as we create through factory method.*/protected Session() {}/*** Create instance through factory method.** param anId* a session id* return a Session object (or derived)* throws PushletException* exception, usually misconfiguration*//** 修改前的create方法 */// public static Session create(String anId) throws PushletException {// Session session;// try {// session (Session) Config.getClass(SESSION_CLASS,// nl.justobjects.pushlet.core.Session).newInstance();// } catch (Throwable t) {// throw new PushletException(// Cannot instantiate Session from config, t);// }//// // Init session// session.id anId;// session.controller Controller.create(session);// session.subscriber Subscriber.create(session);// return session;// }public static Session create(String anId, Event anEvent)throws PushletException {Session session;try {session (Session) Config.getClass(SESSION_CLASS,nl.justobjects.pushlet.core.Session).newInstance();} catch (Throwable t) {throw new PushletException(Cannot instantiate Session from config, t);}// Init sessionsession.id anId;session.controller Controller.create(session);session.subscriber Subscriber.create(session);session.event anEvent;return session;}/*** 增加了getEVent方法*/public Event getEvent() {return event;}/*** Return (remote) Subscriber clients IP address.*/public String getAddress() {return address;}/*** Return command controller.*/public Controller getController() {return controller;}/*** Return Event format to send to client.*/public String getFormat() {return format;}/*** Return (remote) Subscriber clients unique id.*/public String getId() {return id;}/*** Return subscriber.*/public Subscriber getSubscriber() {return subscriber;}/*** Return remote HTTP User-Agent.*/public String getUserAgent() {return userAgent;}/*** Set address.*/protected void setAddress(String anAddress) {address anAddress;}/*** Set event format to encode.*/protected void setFormat(String aFormat) {format aFormat;}/*** Set client HTTP UserAgent.*/public void setUserAgent(String aUserAgent) {userAgent aUserAgent;}/*** Decrease time to live.*/public void age(long aDeltaMillis) {timeToLive - aDeltaMillis;}/*** Has session timed out?*/public boolean isExpired() {return timeToLive 0;}/*** Keep alive by resetting TTL.*/public void kick() {timeToLive LEASE_TIME_MILLIS;}public void start() {SessionManager.getInstance().addSession(this);}public void stop() {subscriber.stop();SessionManager.getInstance().removeSession(this);}/*** Info.*/public void info(String s) {Log.info(S- this : s);}/*** Exceptional print util.*/public void warn(String s) {Log.warn(S- this : s);}/*** Exceptional print util.*/public void debug(String s) {Log.debug(S- this : s);}public String toString() {return getAddress() [ getId() ];}
}/** $Log: Session.java,v $ Revision 1.8 2007/11/23 14:33:07 justb core classes* now configurable through factory* * Revision 1.7 2005/02/28 15:58:05 justb added SimpleListener example* * Revision 1.6 2005/02/28 12:45:59 justb introduced Command class* * Revision 1.5 2005/02/28 09:14:55 justb sessmgr/dispatcher factory/singleton* support* * Revision 1.4 2005/02/25 15:13:01 justb session id generation more robust* * Revision 1.3 2005/02/21 16:59:08 justb SessionManager and session lease* introduced* * Revision 1.2 2005/02/21 12:32:28 justb fixed publish event in Controller* * Revision 1.1 2005/02/21 11:50:46 justb ohase1 of refactoring Subscriber into* Session/Controller/Subscriber*/然后修改了nl.justobjects.pushlet.core.SessionManager修改了createSession方法 // Copyright (c) 2000 Just Objects B.V. justjustobjects.nl
// Distributable under LGPL license. See terms of license at gnu.org.package nl.justobjects.pushlet.core;import nl.justobjects.pushlet.util.Log;
import nl.justobjects.pushlet.util.PushletException;
import nl.justobjects.pushlet.util.Rand;
import nl.justobjects.pushlet.util.Sys;import java.rmi.server.UID;
import java.util.*;
import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;/*** Manages lifecycle of Sessions.** author Just van den Broecke - Just Objects copy;* version $Id: SessionManager.java,v 1.12 2007/12/04 13:55:53 justb Exp $*/
public class SessionManager implements ConfigDefs {/*** Singleton pattern: single instance.*/private static SessionManager instance;static {// Singleton factory pattern: create single instance// from configured class nametry {instance (SessionManager) Config.getClass(SESSION_MANAGER_CLASS,nl.justobjects.pushlet.core.SessionManager).newInstance();Log.info(SessionManager created className instance.getClass());} catch (Throwable t) {Log.fatal(Cannot instantiate SessionManager from config, t);}}/*** Timer to schedule session leasing TimerTasks.*/private Timer timer;private final long TIMER_INTERVAL_MILLIS 60000;/*** Map of active sessions, keyed by their id, all access is through mutex.*/private Map sessions new HashMap(13);/*** Cache of Sessions for iteration and to allow concurrent modification.*/private Session[] sessionCache new Session[0];/*** State of SessionCache, becomes true whenever sessionCache out of sync* with sessions Map.*/private boolean sessionCacheDirty false;/*** Lock for any operation on Sessions (Session Map and/or -cache).*/private final Object mutex new Object();/*** Singleton pattern: protected constructor needed for derived classes.*/protected SessionManager() {}/*** Visitor pattern implementation for Session iteration.* p/* This method can be used to iterate over all Sessions in a threadsafe way.* See Dispatcher.multicast and broadcast methods for examples.** param visitor* the object that should implement method parm* param method* the method to be called from visitor* param args* arguments to be passed in visit method, args[0] will always be* Session object*/public void apply(Object visitor, Method method, Object[] args) {synchronized (mutex) {// Refresh Session cache if required// We use a cache for two reasons:// 1. to prevent concurrent modification from within visitor method// 2. some optimization (vs setting up Iterator for each apply()if (sessionCacheDirty) {// Clear out existing cachefor (int i 0; i sessionCache.length; i) {sessionCache[i] null;}// Refill cache and update statesessionCache (Session[]) sessions.values().toArray(sessionCache);sessionCacheDirty false;}// Valid session cache: loop and call supplied Visitor methodSession nextSession;for (int i 0; i sessionCache.length; i) {nextSession sessionCache[i];// Session cache may not be entirely filledif (nextSession null) {break;}try {// First argument is always a Session objectargs[0] nextSession;// Use Java reflection to call the method passed by the// Visitormethod.invoke(visitor, args);} catch (IllegalAccessException e) {Log.warn(apply: illegal method access: , e);} catch (InvocationTargetException e) {Log.warn(apply: method invoke: , e);}}}}/*** Create new Session (but add later).*//*** public Session createSession(Event anEvent) throws PushletException { * return Session.create(createSessionId());}* * * 这是原来的createSession方法可以看到虽然有anEvent参数··但是却没有在createSession的时候使用*/public Session createSession(Event anEvent) throws PushletException {// Trivialreturn Session.create(createSessionId(), anEvent);}/*** Singleton pattern: get single instance.*/public static SessionManager getInstance() {return instance;}/*** Get Session by session id.*/public Session getSession(String anId) {synchronized (mutex) {return (Session) sessions.get(anId);}}/*** Get copy of listening Sessions.*/public Session[] getSessions() {synchronized (mutex) {return (Session[]) sessions.values().toArray(new Session[0]);}}/*** Get number of listening Sessions.*/public int getSessionCount() {synchronized (mutex) {return sessions.size();}}/*** Get status info.*/public String getStatus() {Session[] sessions getSessions();StringBuffer statusBuffer new StringBuffer();statusBuffer.append(SessionMgr: sessions.length sessions \\n);for (int i 0; i sessions.length; i) {statusBuffer.append(sessions[i] \\n);}return statusBuffer.toString();}/*** Is Session present?.*/public boolean hasSession(String anId) {synchronized (mutex) {return sessions.containsKey(anId);}}/*** Add session.*/public void addSession(Session session) {synchronized (mutex) {sessions.put(session.getId(), session);sessionCacheDirty true;}// log(session.getId() at session.getAddress() adding );info(session.getId() at session.getAddress() added );}/*** Register session for removal.*/public Session removeSession(Session aSession) {synchronized (mutex) {Session session (Session) sessions.remove(aSession.getId());if (session ! null) {info(session.getId() at session.getAddress() removed );}sessionCacheDirty true;return session;}}/*** Starts us.*/public void start() throws PushletException {if (timer ! null) {stop();}timer new Timer(false);timer.schedule(new AgingTimerTask(), TIMER_INTERVAL_MILLIS,TIMER_INTERVAL_MILLIS);info(started; interval TIMER_INTERVAL_MILLIS ms);}/*** Stopis us.*/public void stop() {if (timer ! null) {timer.cancel();timer null;}synchronized (mutex) {sessions.clear();}info(stopped);}/*** Create unique Session id.*/protected String createSessionId() {// Use UUID if specified in config (thanks Uli Romahn)if (Config.hasProperty(SESSION_ID_GENERATION) Config.getProperty(SESSION_ID_GENERATION).equals(SESSION_ID_GENERATION_UUID)) {// We want to be Java 1.4 compatible so use UID class (1.5 we may// use java.util.UUID).return new UID().toString();}// Other cases use random name// Create a unique session id// In 99.9999 % of the cases this should be generated at once// We need the mutext to prevent the chance of creating// same-valued ids (thanks Uli Romahn)synchronized (mutex) {String id;while (true) {id Rand.randomName(Config.getIntProperty(SESSION_ID_SIZE));if (!hasSession(id)) {// Created unique session idbreak;}}return id;}}/*** Util: stdout printing.*/protected void info(String s) {Log.info(SessionManager: new Date() s);}/*** Util: stdout printing.*/protected void warn(String s) {Log.warn(SessionManager: s);}/*** Util: stdout printing.*/protected void debug(String s) {Log.debug(SessionManager: s);}/*** Manages Session timeouts.*/private class AgingTimerTask extends TimerTask {private long lastRun Sys.now();private long delta;private Method visitMethod;public AgingTimerTask() throws PushletException {try {// Setup Visitor Methods for callback from SessionManagerClass[] argsClasses { Session.class };visitMethod this.getClass().getMethod(visit, argsClasses);} catch (NoSuchMethodException e) {throw new PushletException(Failed to setup AgingTimerTask, e);}}/*** Clock tick callback from Timer.*/public void run() {long now Sys.now();delta now - lastRun;lastRun now;debug(AgingTimerTask: tick);// Use Visitor pattern to loop through Session objects (see visit()// below)getInstance().apply(this, visitMethod, new Object[1]);}/*** Callback from SessionManager during apply()*/public void visit(Session aSession) {try {// Age the leaseaSession.age(delta);debug(AgingTimerTask: visit: aSession);// Stop session if lease expiredif (aSession.isExpired()) {info(AgingTimerTask: Session expired: aSession);aSession.stop();}} catch (Throwable t) {warn(AgingTimerTask: Error in timer task : t);}}}
}/** $Log: SessionManager.java,v $ Revision 1.12 2007/12/04 13:55:53 justb* reimplement SessionManager concurrency (prev version was not thread-safe!)* * Revision 1.11 2007/11/23 14:33:07 justb core classes now configurable through* factory* * Revision 1.10 2007/11/10 14:47:45 justb make session key generation* configurable (can use uuid)* * Revision 1.9 2007/11/10 14:17:18 justb minor cosmetic changes just commit now* * Revision 1.8 2007/07/02 08:12:16 justb redo to original version of session* cache (with break, but nullify array first)* * Revision 1.7 2007/07/02 07:33:02 justb small fix in sessionmgr for holes in* sessioncache array (continue i.s.o. break)* * Revision 1.6 2006/11/18 12:13:47 justb made SessionManager constructor* protected to allow constructing derived classes* * Revision 1.5 2005/02/28 15:58:05 justb added SimpleListener example* * Revision 1.4 2005/02/28 12:45:59 justb introduced Command class* * Revision 1.3 2005/02/28 09:14:55 justb sessmgr/dispatcher factory/singleton* support* * Revision 1.2 2005/02/25 15:13:01 justb session id generation more robust* * Revision 1.1 2005/02/21 16:59:09 justb SessionManager and session lease* introduced*/接着··就大胆的修改了nl.justobjects.pushlet.core.EventPullSource这里我修改了 abstract protected Event pullEvent();改为了 abstract protected void pullEvent();83 public void run() {
84 Log.debug(getClass().getName() : starting...);
85 alive true;
86 while (alive) {
87 try {
88
89 Thread.sleep(getSleepTime());
90
91 // Stopped during sleep: end loop.
92 if (!alive) {
93 break;
94 }
95
96 // If passivated wait until we get
97 // get notify()-ied. If there are no subscribers
98 // it wasts CPU to remain producing events...
99 synchronized (this) {
00 while (!active) {
01 Log.debug(getClass().getName() : waiting...);
02 wait();
03 }
04 }
05
06 } catch (InterruptedException e) {
07 break;
08 }
09
10 try {
11 // Derived class should produce an event.
12 Event event pullEvent();
13
14 // Let the publisher push it to subscribers.
15 Dispatcher.getInstance().multicast(event);
16 } catch (Throwable t) {
17 Log.warn(EventPullSource exception while multicasting , t);
18 t.printStackTrace();
19 }
20 }
21 Log.debug(getClass().getName() : stopped);
22 }
23}改为了 public void run() {Log.debug(getClass().getName() : starting...);alive true;while (alive) {try {Thread.sleep(getSleepTime());// Stopped during sleep: end loop.if (!alive) {break;}// If passivated wait until we get// get notify()-ied. If there are no subscribers// it wasts CPU to remain producing events...synchronized (this) {while (!active) {Log.debug(getClass().getName() : waiting...);wait();}}} catch (InterruptedException e) {break;}try {// Derived class should produce an event.pullEvent();// Let the publisher push it to subscribers.//Dispatcher.getInstance().multicast(event);} catch (Throwable t) {Log.warn(EventPullSource exception while multicasting , t);t.printStackTrace();}}Log.debug(getClass().getName() : stopped);}修改的原因··是原来的run线程启动以后会通过getEvent来获得event然后通过 Dispatcher.getInstance().multicast(event); 将事件广播了出去我这里的改造以后的思路是pullEvent不再返回event了线程中也不去进行广播了所有的操作包括event的创建以及event的广播还是单播都在pullEvent中进行。 最后就是js的修改了修改ajax-pushlet-client.js
给PL增加字段parameters修改后如下 var PL {NV_P_FORMAT: p_formatxml-strict,NV_P_MODE: p_modepull,pushletURL: null,webRoot: null,sessionId: null,STATE_ERROR: -2,STATE_ABORT: -1,STATE_NULL: 1,STATE_READY: 2,STATE_JOINED: 3,STATE_LISTENING: 3,state: 1,span stylecolor:#cc0000;parameters:[],/span
......}_doRequest方法修改 _doRequest: function(anEvent, aQuery) { // Check if we are not in any error state if (PL.state 0) { PL._setStatus(died ( PL.state )); return; } // We may have (async) requests outstanding and thus // may have to wait for them to complete and change state. var waitForState false; if (anEvent join || anEvent join-listen) { // We can only join after initialization waitForState (PL.state PL.STATE_READY); } else if (anEvent leave) { PL.state PL.STATE_READY; } else if (anEvent refresh) { // We must be in the listening state if (PL.state ! PL.STATE_LISTENING) { return; } } else if (anEvent listen) { // We must have joined before we can listen waitForState (PL.state PL.STATE_JOINED); } else if (anEvent subscribe || anEvent unsubscribe) { // We must be listeing for subscription mgmnt waitForState (PL.state PL.STATE_LISTENING); } else { // All other requests require that we have at least joined waitForState (PL.state PL.STATE_JOINED); } // May have to wait for right state to issue request if (waitForState true) { PL._setStatus(anEvent , waiting... state PL.state); setTimeout(function() { PL._doRequest(anEvent, aQuery); }, 100); return; } // ASSERTION: PL.state is OK for this request // Construct base URL for GET var url PL.pushletURL ?p_event anEvent; // Optionally attach query string if (aQuery) { url url aQuery; } // Optionally attach session id if (PL.sessionId ! null) { url url p_id PL.sessionId; if (anEvent p_leave) { PL.sessionId null; } }
//这里是我修改的地方我的数组中的偶数是参数名奇数是参数内容这里把我的参数拼接到了url中。 if(PL.parameters.length 0) { url PL.parameters[0] PL.parameters[1]; } PL.debug(_doRequest, url); PL._getXML(url, PL._onResponse); // uncomment to use synchronous XmlHttpRequest //var rsp PL._getXML(url); //PL._onResponse(rsp); */ }, 额修改完了可以配置pushlet的相关参数来使用pushlet了。 在web.xml中配置如下参数 servletservlet-namepushlet/servlet-nameservlet-classnl.justobjects.pushlet.servlet.Pushlet/servlet-classload-on-startup3/load-on-startup/servletservlet-mappingservlet-namepushlet/servlet-nameurl-pattern/admin/pushlet.srv/url-pattern/servlet-mapping这是pushlet配置的基本参数这里我配置的是/admin/pushlet.srv是因为项目的路径是localhost:8080/项目名 ,而我的页面是在localhost:8080/项目名/admin/下面所以加了/admin/pushlet.srv。如果你的页面就在项目目录下就不用加前面的/admin了。 在sources.properties中配置如下参数 #
# Properties file for EventSource objects to be instantiated.
#
# Place this file in the CLASSPATH (e.g. WEB-INF/classes) or directly under WEB-INF.
#
# $Id: sources.properties,v 1.2 2007/11/10 14:12:16 justb Exp $
#
# Each EventSource is defined as keyclassname
# 1. key should be unique within this file but may be any name
# 2. classname is the full class name
#
#
# Define Pull Sources here. These classes must be derived from
# nl.justobjects.pushlet.core.EventPullSource
# Inner classes are separated with a $ sign from the outer class.
source1org.calonlan.soulpower.plug.HwPushlet$MessClazz
# TO BE DONE IN NEXT VERSION
# define Push Sources here. These must implement the interface
# nl.justobjects.pushlet.core.EventSource这里把我的pushlet的实现类配置进去了。 最后就是如何使用了。 单播 package org.calonlan.soulpower.plug;import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;import nl.justobjects.pushlet.core.Dispatcher;
import nl.justobjects.pushlet.core.Event;
import nl.justobjects.pushlet.core.EventPullSource;
import nl.justobjects.pushlet.core.Session;
import nl.justobjects.pushlet.core.SessionManager;public class HwPushlet {private static String driver com.mysql.jdbc.Driver;private static String dbName dlw;private static String userName root;private static String passWord root;private static String url jdbc:mysql://localhost:3306/;static public class MessClazz extends EventPullSource {Overrideprotected long getSleepTime() {return 1000 * 60 * 3;}Overrideprotected void pullEvent() {Session[] sessions SessionManager.getInstance().getSessions();for (int i 0; i sessions.length; i) {String userId sessions[i].getEvent().getField(uid);Event event Event.createDataEvent(/mipc/he);Connection conn null;String x ;try {Class.forName(driver);conn DriverManager.getConnection(url dbName, userName,passWord);Statement statement conn.createStatement();String sql select * from weiorder where mystate0 and bname userId ;ResultSet rst statement.executeQuery(sql);if (rst.next()) {x 1;} else {x 2;}} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();} finally {try {conn.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}event.setField(mess, x);Dispatcher.getInstance().unicast(event, sessions[i].getId());}}}}我这里是服务器的实现在单播的时候查找前台传过来的uid中是否有消息有的话返回一个1没有就返回一个2最重要的是Dispatcher.getInstance().unicast(event, sessions[i].getId());这一句通过单播的形式把消息传递给指定session的用户。 页面js代码 script typetext/javascript
PL.parameters.push(uid);
PL.parameters.push(${user.username});
PL._init();
PL.joinListen(/mipc/he);
function onData(event) {if(event.get(mess)1){$.messager.show({title:系统消息,msg:您有新的订单请注意处理,timeout:0,showType:slide});document.getElementById(audio_player).play();}// 离开 // PL.leave();
}
/script广播广播的还js页面的请求就和官网一样了pullEvent中也只是简单的进行广播。代码如下 package org.calonlan.soulpower.plug;import nl.justobjects.pushlet.core.Dispatcher;
import nl.justobjects.pushlet.core.Event;
import nl.justobjects.pushlet.core.EventPullSource;public class HwPushlet {static public class MessClazz extends EventPullSource {Overrideprotected long getSleepTime() {return 1000 * 60 * 3;}Overrideprotected void pullEvent() {Event event Event.createDataEvent(/mipc/he);String x ;event.setField(mess, x);Dispatcher.getInstance().multicast(event);}}}额时间比较仓促···最近项目太忙了唉。这里简单的记录一下。也不知道这种是不是很落后或是很复杂的修改方法。还忘高手们批评指正。修改后的jar包和js请在http://download.csdn.net/detail/u012613903/9483881下载。
