Why JMS is used to send messages? Why not we just send emails, or text strings? Is there any difference?
Using JMS and sending messages, does it mean that we are sending the messages across different applications or within an application between components like form bean-dao, etc?
Why so hype is there in just sending the message using JMS?
It is not like that I have not made any effort in understanding JMS but still have some questions about JMS. I know JMS is that MOM(message oriented middleware server) which has DO(destination objects) so MOM server has atleast 2 clients either of the side. Sender and Receiver. There can be N no. of senders/receivers connected with same or multiple DO in MOM server.
JMS has two mdels:-
1) Publisher/Subscribers - here DO is topic. In this, every messages sent to DO from every senders are received by every receivers
connected with the same DO.
2) Point-to-point - here DO is queue. In this, every message sent to DO from any/evry sender is received by only one receiving client
although there can N receivers but only one will get.
These communication is known as asynchronous because sender client has no concern about the receiver client whether receiver is up or not. On the other hand synchronous communication is your RMI which is a tightly coupled communication where both sender/receiver must be in sync, active, listening and must know each others credentials to connect with.
Only 5 types of messages can be sent over JMS:-
1) Text messages
2) Stream
3) Byte
4) Object
5) Map messages
JMS can be used in CRM/Inventory control systems.
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I know this much only. I'm new to this. Please add if I have left or missed something
I want to run some examples also. Please suggest me some good applicaition servers. Can I use eclipse to
test JMS?
Please explain me breifly.
