Package org.eclipse.jetty.servlets

Class EventSourceServlet

java.lang.Object

javax.servlet.GenericServlet

javax.servlet.http.HttpServlet

org.eclipse.jetty.servlets.EventSourceServlet

All Implemented Interfaces:

java.io.Serializable, javax.servlet.Servlet, javax.servlet.ServletConfig

public abstract class EventSourceServlet
extends javax.servlet.http.HttpServlet

A servlet that implements the event source protocol, also known as "server sent events".

This servlet must be subclassed to implement abstract method newEventSource(HttpServletRequest) to return an instance of EventSource that allows application to listen for event source events and to emit event source events.

This servlet supports the following configuration parameters:

• heartBeatPeriod, that specifies the heartbeat period, in seconds, used to check whether the connection has been closed by the client; defaults to 10 seconds.

NOTE: there is currently no support for last-event-id.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	EventSourceServlet.EventSourceEmitter

Field Summary

Fields

Modifier and Type	Field	Description
private static byte[]	COMMENT_FIELD
private static byte[]	CRLF
private static byte[]	DATA_FIELD
private static byte[]	EVENT_FIELD
private int	heartBeatPeriod
private java.util.concurrent.ScheduledExecutorService	scheduler

Constructor Summary

Constructors

Constructor	Description
EventSourceServlet()

Method Summary

Modifier and Type	Method	Description
void	destroy()
protected void	doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)
void	init()
protected abstract EventSource	newEventSource(javax.servlet.http.HttpServletRequest request)
protected void	open(EventSource eventSource, EventSource.Emitter emitter)
protected void	respond(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)

Methods inherited from class javax.servlet.http.HttpServlet

doDelete, doHead, doOptions, doPost, doPut, doTrace, getLastModified, service, service

Methods inherited from class javax.servlet.GenericServlet

getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, log, log

Methods inherited from class java.lang.Object

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

Field Detail

CRLF

private static final byte[] CRLF

EVENT_FIELD

private static final byte[] EVENT_FIELD

DATA_FIELD

private static final byte[] DATA_FIELD

COMMENT_FIELD

private static final byte[] COMMENT_FIELD

scheduler

private java.util.concurrent.ScheduledExecutorService scheduler

heartBeatPeriod

private int heartBeatPeriod

Constructor Detail

EventSourceServlet

public EventSourceServlet()

Method Detail

init

public void init()
          throws javax.servlet.ServletException

Overrides:

init in class javax.servlet.GenericServlet

Throws:

javax.servlet.ServletException

destroy

public void destroy()

Specified by:

destroy in interface javax.servlet.Servlet

Overrides:

destroy in class javax.servlet.GenericServlet

doGet

protected void doGet(javax.servlet.http.HttpServletRequest request,
                     javax.servlet.http.HttpServletResponse response)
              throws javax.servlet.ServletException,
                     java.io.IOException

Overrides:

doGet in class javax.servlet.http.HttpServlet

Throws:

javax.servlet.ServletException

java.io.IOException

newEventSource

protected abstract EventSource newEventSource(javax.servlet.http.HttpServletRequest request)

respond

protected void respond(javax.servlet.http.HttpServletRequest request,
                       javax.servlet.http.HttpServletResponse response)
                throws java.io.IOException

Throws:

java.io.IOException

open

protected void open(EventSource eventSource,
                    EventSource.Emitter emitter)
             throws java.io.IOException

Throws:

java.io.IOException