com.dxfeed.event.misc

Class Message

java.lang.Object

com.dxfeed.event.misc.Message

All Implemented Interfaces:

EventType<String>, Serializable

public class Message
extends Object
implements EventType<String>

Message event with application-specific attachment. Messages are never conflated and are delivered to all connected subscribers. There is no built-in persistence for messages. They are lost when subscribers are not connected to the message publisher, so they shall be only used for notification purposes in addition to persistence mechanism.

Properties

Message event has the following properties:

• eventSymbol - symbol of this event;
• attachment - attachment.

Implementation details

This event is implemented on top of QDS record Message.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Message() Creates new message with default values.
Message(String eventSymbol) Creates new message with the specified event symbol.
Message(String eventSymbol, Object attachment) Creates new message with the specified event symbol and attachment.

Method Summary

Modifier and Type	Method and Description
Object	getAttachment() Returns attachment.
Object	getAttachment(ClassLoader cl) Returns attachment.
String	getEventSymbol() Returns symbol for this event.
long	getEventTime() Returns time when event was created or zero when time is not available.
void	setAttachment(Object attachment) Changes attachment.
void	setEventSymbol(String eventSymbol) Changes symbol for this event.
void	setEventTime(long eventTime) Changes event creation time.
String	toString() Returns string representation of this message event.

Methods inherited from class java.lang.Object

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

Constructor Detail

Message

public Message()

Creates new message with default values.

Message

public Message(String eventSymbol)

Creates new message with the specified event symbol.

Parameters:

eventSymbol - event symbol.

Message

public Message(String eventSymbol,
               Object attachment)

Creates new message with the specified event symbol and attachment.

Parameters:

eventSymbol - event symbol.

attachment - attachment.

Method Detail

getEventSymbol

public String getEventSymbol()

Returns symbol for this event.

Specified by:

getEventSymbol in interface EventType<String>

Returns:

event symbol.

setEventSymbol

public void setEventSymbol(String eventSymbol)

Changes symbol for this event.

Specified by:

setEventSymbol in interface EventType<String>

Parameters:

eventSymbol - event symbol.

getEventTime

public long getEventTime()

Returns time when event was created or zero when time is not available.

This event time is available only when the corresponding DXEndpoint is created with DXENDPOINT_EVENT_TIME_PROPERTY and the data source has embedded event times. This is typically true only for data events that are read from historical tape files and from OnDemandService. Events that are coming from a network connections do not have an embedded event time information and this method will return zero for them, meaning that event was received just now.

Specified by:

getEventTime in interface EventType<String>

Returns:

the difference, measured in milliseconds, between the event creation time and midnight, January 1, 1970 UTC or zero when time is not available.

setEventTime

public void setEventTime(long eventTime)

Changes event creation time.

Specified by:

setEventTime in interface EventType<String>

Parameters:

eventTime - the difference, measured in milliseconds, between the event creation time and midnight, January 1, 1970 UTC.

getAttachment

public Object getAttachment()

Returns attachment.

Throws:

RuntimeException - if object cannot be deserialized from its serial form

getAttachment

public Object getAttachment(ClassLoader cl)

Returns attachment.

Parameters:

cl - the ClassLoader that will be used to load classes; null for default

Throws:

RuntimeException - if object cannot be deserialized from its serial form

setAttachment

public void setAttachment(Object attachment)

Changes attachment.

Parameters:

attachment - attachment.

toString

public String toString()

Returns string representation of this message event.

Overrides:

toString in class Object