1. What is JMS topic?

A distribution mechanism for publishing messages that are delivered to multiple subscribers.

2. What is JMS queue?

A staging area that contains messages that have been sent and are waiting to be read. Note that, contrary to what the name queue suggests, messages don't have to be delivered in the order sent. If the message driven bean pool contains more than one instance then messages can be processed concurrently and thus it is possible that a later message is processed sooner than an earlier one. A JMS queue guarantees only that each message is processed only once.

3. What is JMS message?

An object that contains the data being transferred between JMS clients.

4. What is JMS consumer?

A JMS client that receives messages.

5. What is JMS producer?

A JMS client that creates and sends messages.

6. Wat is JMS client?

An application or process that produces and/or receives messages.

7. What is JMS provider?

An implementation of the JMS interface for a Message Oriented Middleware (MOM). Providers are implemented as either a Java JMS implementation or an adapter to a non-Java MOM.

8. What is the use of MapMessage?

A MapMessage carries name-value pair as it's payload. Thus it's payload is similar to the java.util.Properties object of Java. The values can be Java primitives or their wrappers

9. What is the use of TextMessage?

TextMessage contains instance of java.lang.String as it's payload. Thus it is very useful for exchanging textual data. It can also be used for exchanging complex character data such as an XML document.

10. What is the basic difference between Publish Subscribe model and P2P model?

Publish Subscribe model is typically used in one-to-many situation. It is unreliable but very fast. P2P model is used in one-to-one situation. It is highly reliable.

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