net.fortytwo.stream

Interface Subscription

All Known Implementing Classes:

BasicSubscription

public interface Subscription

An object which manages the connection to a continuous query and its solutions

Author:

Joshua Shinavier (http://fortytwo.net)

Method Summary

Modifier and Type	Method and Description
void	cancel() Marks this subscription as inactive, so that the query no longer receives results
java.lang.String	getId()
boolean	isActive()
boolean	renew(int ttl) Renews the subscription for another ttl milliseconds (or indefinitely, if ttl=0), provided the renewal operation is accepted by the query engine.

Method Detail

getId

java.lang.String getId()

Returns:

a globally unique id for this subscription

isActive

boolean isActive()

Returns:

whether this subscription is still registered with the StreamProcessor (occupying resources and potentially receiving and handling query results)

cancel

void cancel()
     throws java.io.IOException

Marks this subscription as inactive, so that the query no longer receives results

Throws:

java.io.IOException - if there is a problem communicating with this query engine (for example, if there are network operations involved)

renew

boolean renew(int ttl)
       throws java.io.IOException

Renews the subscription for another ttl milliseconds (or indefinitely, if ttl=0), provided the renewal operation is accepted by the query engine.

Parameters:

ttl - the new time-to-live in seconds, or 0 for infinite time-to-live

Returns:

whether the subscription was successfully renewed

Throws:

java.io.IOException - if there is a problem communicating with this query engine (for example, if there are network operations involved)