org.cometd.server.transport

Class LongPollingTransport

java.lang.Object

org.cometd.common.AbstractTransport

org.cometd.server.AbstractServerTransport

org.cometd.server.transport.HttpTransport

org.cometd.server.transport.LongPollingTransport

All Implemented Interfaces:

ServerTransport, Transport

Direct Known Subclasses:

JSONPTransport, JSONTransport

public abstract class LongPollingTransport
extends HttpTransport

Abstract Long Polling Transport.

Transports based on this class can be configured with servlet init parameters:

browserId

The Cookie name used to save a browser ID.

maxSessionsPerBrowser

The maximum number of long polling sessions allowed per browser.

multiSessionInterval

The polling interval to use once max session per browser is exceeded.

autoBatch

If true a batch will be automatically created to span the handling of messages received from a session.

allowMultiSessionsNoBrowser

Allows multiple sessions even when the browser identifier cannot be retrieved.

Nested Class Summary

Nested classes/interfaces inherited from class org.cometd.server.AbstractServerTransport

AbstractServerTransport.OneTimeScheduler, AbstractServerTransport.Scheduler

Field Summary

Fields

Modifier and Type	Field and Description
static String	ALLOW_MULTI_SESSIONS_NO_BROWSER_OPTION
static String	AUTOBATCH_OPTION
static String	BROWSER_ID_OPTION
static String	MAX_SESSIONS_PER_BROWSER_OPTION
static String	MULTI_SESSION_INTERVAL_OPTION
static String	PREFIX

Fields inherited from class org.cometd.server.transport.HttpTransport

JSON_DEBUG_OPTION, MESSAGE_PARAM

Fields inherited from class org.cometd.server.AbstractServerTransport

INTERVAL_OPTION, MAX_INTERVAL_OPTION, MAX_LAZY_TIMEOUT_OPTION, MAX_QUEUE_OPTION, META_CONNECT_DELIVERY_OPTION, RANDOMIZE_LAZY_TIMEOUT_OPTION, TIMEOUT_OPTION

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	LongPollingTransport(BayeuxServerImpl bayeux, String name)

Method Summary

Methods

Modifier and Type	Method and Description
protected ServerMessage.Mutable	bayeuxServerHandle(ServerSessionImpl session, ServerMessage.Mutable message)
protected void	decBrowserId(String browserId)
protected String	findBrowserId(javax.servlet.http.HttpServletRequest request)
protected abstract void	finishWrite(PrintWriter writer, ServerSessionImpl session)
void	handle(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)
protected void	handleJSONParseException(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response, String json, Throwable exception)
protected boolean	incBrowserId(String browserId) Increment the browser ID count.
protected void	init() Initialise the transport, resolving default and direct options.
protected abstract boolean	isAlwaysFlushingAfterHandle()
protected void	metaConnectResumed(javax.servlet.http.HttpServletRequest request, ServerSession session)
protected void	metaConnectSuspended(javax.servlet.http.HttpServletRequest request, ServerSession session, long timeout)
protected abstract ServerMessage.Mutable[]	parseMessages(javax.servlet.http.HttpServletRequest request)
protected ServerMessage.Mutable[]	parseMessages(String[] requestParameters)
protected String	setBrowserId(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)
protected void	sweep() Sweep the transport for old Browser IDs
protected abstract PrintWriter	writeMessage(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response, PrintWriter writer, ServerSessionImpl session, ServerMessage message)

Methods inherited from class org.cometd.server.transport.HttpTransport

accept, getContext, getCurrentRequest, setCurrentRequest

Methods inherited from class org.cometd.server.AbstractServerTransport

debug, destroy, getAdvice, getBayeux, getInterval, getMaxInterval, getMaxLazyTimeout, getTimeout, isMetaConnectDeliveryOnly, parseMessages, parseMessages, setAdvice, setInterval, setMaxInterval, setMaxLazyTimeout, setMetaConnectDeliveryOnly, setTimeout

Methods inherited from class org.cometd.common.AbstractTransport

getName, getOption, getOption, getOption, getOption, getOption, getOptionNames, getOptionPrefix, setOption, setOptionPrefix

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.cometd.bayeux.Transport

getName, getOption, getOptionNames, getOptionPrefix

Field Detail

PREFIX

public static final String PREFIX

See Also:

Constant Field Values

BROWSER_ID_OPTION

public static final String BROWSER_ID_OPTION

See Also:

Constant Field Values

MAX_SESSIONS_PER_BROWSER_OPTION

public static final String MAX_SESSIONS_PER_BROWSER_OPTION

See Also:

Constant Field Values

MULTI_SESSION_INTERVAL_OPTION

public static final String MULTI_SESSION_INTERVAL_OPTION

See Also:

Constant Field Values

AUTOBATCH_OPTION

public static final String AUTOBATCH_OPTION

See Also:

Constant Field Values

ALLOW_MULTI_SESSIONS_NO_BROWSER_OPTION

public static final String ALLOW_MULTI_SESSIONS_NO_BROWSER_OPTION

See Also:

Constant Field Values

Constructor Detail

LongPollingTransport

protected LongPollingTransport(BayeuxServerImpl bayeux,
                    String name)

Method Detail

init

protected void init()

Description copied from class: AbstractServerTransport

Initialise the transport, resolving default and direct options.

Overrides:

init in class AbstractServerTransport

findBrowserId

protected String findBrowserId(javax.servlet.http.HttpServletRequest request)

setBrowserId

protected String setBrowserId(javax.servlet.http.HttpServletRequest request,
                  javax.servlet.http.HttpServletResponse response)

incBrowserId

protected boolean incBrowserId(String browserId)

Increment the browser ID count.

Parameters:

browserId - the browser ID to increment the count for

Returns:

true if the browser ID count is below the max sessions per browser value. If false is returned, the count is not incremented.

decBrowserId

protected void decBrowserId(String browserId)

handle

public void handle(javax.servlet.http.HttpServletRequest request,
          javax.servlet.http.HttpServletResponse response)
            throws IOException,
                   javax.servlet.ServletException

Specified by:

handle in class HttpTransport

Throws:

IOException

javax.servlet.ServletException

bayeuxServerHandle

protected ServerMessage.Mutable bayeuxServerHandle(ServerSessionImpl session,
                                       ServerMessage.Mutable message)

metaConnectSuspended

protected void metaConnectSuspended(javax.servlet.http.HttpServletRequest request,
                        ServerSession session,
                        long timeout)

metaConnectResumed

protected void metaConnectResumed(javax.servlet.http.HttpServletRequest request,
                      ServerSession session)

handleJSONParseException

protected void handleJSONParseException(javax.servlet.http.HttpServletRequest request,
                            javax.servlet.http.HttpServletResponse response,
                            String json,
                            Throwable exception)
                                 throws javax.servlet.ServletException,
                                        IOException

Throws:

javax.servlet.ServletException

IOException

sweep

protected void sweep()

Sweep the transport for old Browser IDs

Overrides:

sweep in class AbstractServerTransport

See Also:

AbstractServerTransport.sweep()

parseMessages

protected ServerMessage.Mutable[] parseMessages(String[] requestParameters)
                                         throws IOException,
                                                ParseException

Throws:

IOException

ParseException

parseMessages

protected abstract ServerMessage.Mutable[] parseMessages(javax.servlet.http.HttpServletRequest request)
                                                  throws IOException,
                                                         ParseException

Throws:

IOException

ParseException

isAlwaysFlushingAfterHandle

protected abstract boolean isAlwaysFlushingAfterHandle()

Returns:

true if the transport always flushes at the end of a call to handle(HttpServletRequest, HttpServletResponse).

writeMessage

protected abstract PrintWriter writeMessage(javax.servlet.http.HttpServletRequest request,
                       javax.servlet.http.HttpServletResponse response,
                       PrintWriter writer,
                       ServerSessionImpl session,
                       ServerMessage message)
                                     throws IOException

Throws:

IOException

finishWrite

protected abstract void finishWrite(PrintWriter writer,
               ServerSessionImpl session)
                             throws IOException

Throws:

IOException