Scenario: given below:
i) good for transaction processing
ii) network need not be available, messages can be queued
iii) tight coupling between sender and receiver
iv) network must be available
which of the cases are not suitable for synchronous communication?
a. case i and ii only.
b. case iii and iv only.
c case i , iii, iv
d. case ii, iii, iv
e. case i, ii, iii
f. case ii only.
Answer: f
JMS provides a standard Java-based interface to the message services of a MOM of some other provider. Messaging systems can be either asynchronous or synchronous and can be classified into different models that determine which client receives a message.
Synchronus messages are more suitable for good transaction processing, fail-safe communication and coping with error situations. It increases the coupling between sender and receiver. Blocks sender until the receiver is finished processing. Network must be available. More demanding on communication mechanisms.
I think the answer should be a).
"Synchronous messages are more suitable for good transaction processing"
I think with asynchronous messaging, a transaction can be done. For example, a
servlet A asynchronously dispatches a transaction task to servlet B.