Java Interview Questions

steps to write Sender application :-
a)We have to get the QueueConnection through jndi.
b)Create QueueSession by invoking a method createQueueSession() .
c)Create a Queue object by invoking createQueue() on QueueSession interface.
d)Create a QueueSender object of a Queue by invoking createSender(javax.jms.Queue q)
on QueueSession.
e)Create TextMessage object and set the text to be send .
f)Send the message by using a method send() .

steps to write Receiver application :-
a)We have to get the QueueConnection through jndi.
b)Create QueueSession by invoking a method createQueueSession() .
c)Create a Queue object by invoking createQueue() on QueueSession interface.
d)Create a QueueReceiver object of a Queue by invoking createReceiver(javax.jms.Queue) on QueueSession.

DurableSubscription :-
DurableSubscription indicates that the client wants to recive all the messages published to a topic,including messages published when the client connection is not active.

Non-DurableSubscription :-
Non-DurableSubscription will not recive the messages published when the client connection is not active.

steps to write Publisher (sender) application :-
———————————————–
a)We have to get the TopicConnection through jndi.
b)Create TopicSession by invoking a method createTopicSession() .
c)create a Topic object by invoking createTopic() on TopicSession interface.
d)create a TopicPublisher object of a Topic by invoking createPublisher(javax.jms.Topic t) on TopicSession.(t is a Topic object that specifies the Topic we want to subscribe to).
e)create TextMessage object and set the text to be published .
f)publish the message by using a method publish() in Publisher interface .

steps to write subscriber (receiver) application :-
————————————————–
a)We have to get the TopicConnection through jndi.
b)Create TopicSession by invoking a method createTopicSession() .
c)create a Topic object by invoking createTopic() on TopicSession interface.
d)create a TopicSubscriber object of a Topic by invoking createSubscriber(javax.jms.Topic) or
createDurableSubscriber(javax.jms.Topic t,String name,String messageselector,boolean nolocal) on TopicSession.

t               ——> is a Topic object that specifies the Topic we want to subscribe to.
name           —> is a String that indicates the name under which to maintain the Durable Subscribtion to the specified topic.
messageselector –> is a String that defines selection criteria.
nolocal    ——-> is a boolean if it is true the Subscriber will not recive messages that were published by the client application .