Types of Providers

Providers are categorized according to the types of requests they service. The Sun WBEM SDK supports four types of providers:

• Instance – Supply dynamic instances of a given class, for example, Solaris packages. Instance providers support one or more of the following operations:

  • Instance retrieval

  • Enumeration

  • Modification

  • Deletion

• Property – Supply dynamic property values, for example, disk space.

• Method – Supply methods of one or more classes. A method is a function that describes the behavior of a class. Methods must be implemented by a provider.

• Association – Supply instances of dynamic association classes.

• Event — Handle indications of CIM events. Event providers are described in Chapter 6, Handling CIM Events.

A single provider can support instances, properties, methods, and associations, which can be convenient.

Most providers are pull providers, which means they maintain their own data, generating it dynamically when necessary. Pull providers have minimal interaction with the CIM Object Manager and the CIM Repository. The data managed by a pull provider typically changes frequently, requiring the provider to either generate the data dynamically or retrieve it from a local cache whenever an application issues a request. A provider can also contact the CIM Object Manager.

A single provider can act simultaneously as a class, instance, and method provider by proper registration and implementation of all relevant methods.