What is JMS and Why JMS Required ?
- Messaging is a method of communication between software components or applications.
- The Java Message Service (JMS) is a standard API that allows applications to create, send, receive, and read messages that is part of J2EE
- Difference between JMS and Email Message?
- JMS is to MOM like JDBC to RDBMS
Options for JMS Persistence
- File systemspersitence
What is difference between Persistent Message and non-persistent message ?
· The message cannot be lost due to a JMS provider failure.
· Message must not be delivered twice.
· It is not considered sent until it has been safely written to a file or database.
· WebLogic JMS writes persistent messages to a WebLogic persistent store (disk-base file or JDBC-accessible database) that is optionally targeted by each JMS server during configuration.
· They are guaranteed to be delivered at-most-once, unless there is a JMS provider failure, in which case messages may be lost, and must not be delivered twice.
· If a connection is closed or recovered, all non-persistent messages that have not yet been acknowledged will be redelivered.
· Once a non-persistent message is acknowledged, it will not be redelivered.