Types of messaging

There are two types of messaging domains to be chosen from, as per the requirement:

• Point-to-point messaging:

  • Each message has only one consumer

  • There is no timing dependency

• Publish-Subscribe messaging:

  • Each message has many consumers

  • Messages have a timing dependency - when an application sends a message to the messaging agent, the consumer needs to subscribe and be active to receive the messages

Message consumers

These are the ways of consuming messages provided by JMS API:

• Message listeners

  • They provide an asynchronous messaging model

  • Listeners are like event watchers/listeners; whenever a message is available, the listener ensures that it reaches its destination

  • Listeners will call the onMessage() method

• The receive() method

  • It provides a synchronous messaging model()

  • Messages are consumed by explicitly calling the receive() method from the connection factory

Message structure

A message consists of three parts:

• Header: This contains information about the destination and timestamp...