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pushlet单播与多播
2016-04-08 09:23:30         来源:萝卜地里的兔子的博客  
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pushlet单播与多播: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. 
// 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 ©
 * @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 session
		session.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 client's 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 client's 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. 
// 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 ©
 * @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 name
		try {
			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.
	 *

* 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 cache for (int i = 0; i < sessionCache.length; i++) { sessionCache[i] = null; } // Refill cache and update state sessionCache = (Session[]) sessions.values().toArray( sessionCache); sessionCacheDirty = false; } // Valid session cache: loop and call supplied Visitor method Session nextSession; for (int i = 0; i < sessionCache.length; i++) { nextSession = sessionCache[i]; // Session cache may not be entirely filled if (nextSession == null) { break; } try { // First argument is always a Session object args[0] = nextSession; // Use Java reflection to call the method passed by the // Visitor method.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 { // Trivial return 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 id break; } } 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 SessionManager Class[] 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 lease aSession.age(delta); debug("AgingTimerTask: visit: " + aSession); // Stop session if lease expired if (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_format=xml-strict',
	NV_P_MODE: 'p_mode=pull',
	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,
	parameters:[],
......}
_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

	
		pushlet
		nl.justobjects.pushlet.servlet.Pushlet
		3
	
	
		pushlet
		/admin/pushlet.srv
	

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 =
# 1.  should be unique within this file but may be any name
# 2.  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. 
source1=org.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 {

		@Override
		protected long getSleepTime() {
			return 1000 * 60 * 3;
		}

		@Override
		protected 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 mystate='0' and bname='"
							+ userId + "'";
					ResultSet rst = statement.executeQuery(sql);
					if (rst.next()) {
						x = "1";
					} else {
						x = "2";
					}

				} catch (ClassNotFoundException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				} catch (SQLException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				} finally {
					try {
						conn.close();
					} catch (SQLException e) {
						// TODO Auto-generated catch block
						e.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

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 {

		@Override
		protected long getSleepTime() {
			return 1000 * 60 * 3;
		}

		@Override
		protected void pullEvent() {

			Event event = Event.createDataEvent("/mipc/he");
			String x = "";

			event.setField("mess", x);
			Dispatcher.getInstance().multicast(event);

		}

	}

}

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https://download.csdn.net/detail/u012613903/9483881下载。

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