Apache Axis2 - Core Modules

Core Modules

• XML Processing Model: Managing or processing the SOAP message is the most difficult part of the execution of a message. The efficiency of message processing is the single most important factor that decides the performance of the entire system. Axis1 uses DOM as its message representation mechanism.
  

However, Axis2 introduced a fresh XML InfoSet-based representation for SOAP messages. It is known as AXIOM (AXIs Object Model). AXIOM encapsulates the complexities of efficient XML processing within the implementation.

• SOAP Processing Model: This model involves the processing of an incoming
  
  
• SOAP message. The model defines the different stages (phases) that the execution will walk through. The user can then extend the processing model in specific places.
  
  
• Information Model: This keeps both static and dynamic states and has the logic to process them. The information model consists of two hierarchies to keep static and run-time information separate. Service life cycle and service session management are two objectives in the information model.
  
  
• Deployment Model: The deployment model allows the user to easily deploy the services, configure the transports, and extend the SOAP Processing Model. It also introduces newer deployment mechanisms in order to handle hot deployment, hot updates, and J2EE-style deployment.
  
  
• Client API: This provides a convenient API for users to interact with Web Services using Axis2. The API consists of two sub-APIs, for average and advanced users. Axis2 default implementation supports all the eight MEPs (Message Exchange Patterns) defined in WSDL 2.0. The API also allows easy extension to support custom MEPs.

• Transports: Axis2 defines a transport framework that allows the user to use and expose the same service in multiple transports. The transports fit into specific places in the SOAP processing model. The implementation, by default, provides a few common transports (HTTP, SMTP, JMX, TCP and so on). However, the user can write or plug-in custom transports, if needed.