cgl.narada.discovery.topics
Class TopicDiscoveryClient

java.lang.Object
  cgl.narada.discovery.topics.TopicDiscoveryClient

All Implemented Interfaces:

NBEventListener

public class TopicDiscoveryClient
extends Object
implements NBEventListener

Topic Discovery Client can be used to discover topic UUIDs by querying TDN
Created on Apr 8, 2005

Constructor Summary

TopicDiscoveryClient(int clientEntityId, String configFile, Certificate _creds, PrivateKey _priv, String host, String port, String protocol)
Creates a TopicDiscoveryClient for discovering topics
Assumes that the host/port/protocol of the broker have been previously determined (using for e.g.

Method Summary

void	close()
SignedTopicAdvertisement[]	discover(int queryType, String query, String TDN_ID, int maxResponses) Utility function to discover a topic.
static void	main(String[] args)
void	onEvent(NBEvent nbEvent) Upon the receipt of an event which has satisfied all the constraints, if any were provided, that needed to be satisfied prior to delivery
void	send(String topicName, byte[] request) Publishes the specified request(bytes) on the specifed topic

Methods inherited from class java.lang.Object

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

Constructor Detail

TopicDiscoveryClient

public TopicDiscoveryClient(int clientEntityId,
                            String configFile,
                            Certificate _creds,
                            PrivateKey _priv,
                            String host,
                            String port,
                            String protocol)

Creates a TopicDiscoveryClient for discovering topics
Assumes that the host/port/protocol of the broker have been previously determined (using for e.g. the broker discovery mechanisms)

Parameters:

clientEntityId - clientId to use

configFile - Path to ServiceConfiguration.txt file

_creds - Client certificate

_priv - Client's private key

host - The host where a broker is running

port - The port to which to connect to

protocol - Protocol to use

Method Detail

discover

public SignedTopicAdvertisement[] discover(int queryType,
                                           String query,
                                           String TDN_ID,
                                           int maxResponses)

Utility function to discover a topic. This function waits until a topic discovery response was recieved or a timeout occurred

Parameters:

queryType - - Type of query (String, INT, TaG-value etc...

query - - The query for discovering topics

TDN_ID - - IF NULL, broadcast the query on TOPIC_DISCOVERY topic, else can specify a specific TDN to target this query

Returns:

An array of TopicAdvertisement objects if TDNs could match the request, Empty array otherwise

send

public void send(String topicName,
                 byte[] request)

Publishes the specified request(bytes) on the specifed topic

Parameters:

topicName - - The topic to which the request must be published

request - - The request to be published (in bytes)

close

public void close()

onEvent

public void onEvent(NBEvent nbEvent)

Description copied from interface: NBEventListener

Upon the receipt of an event which has satisfied all the constraints, if any were provided, that needed to be satisfied prior to delivery

Specified by:

onEvent in interface NBEventListener

main

public static void main(String[] args)