Jini technology infrastructure (1)
Jini technology plug-and-play infrastructure agreement mainly by three groups: the View (Lookup), found (Discovery) and the accession (Join). Search services are distributed Jini the basic components of the system, provides a distributed Jini system in the central registration system services. In the Jini system, the programs can find the method of choice for service through the View services, and Search service is available to administrators and users visit various interface basis.
View the service model
Lookup Service preserved a service table, the table of representatives of each element of the system can be used in a service, which preserved a visit by the needs of the service code and a description of a series of scalable service attributes. Figuratively speaking, find services like telephone directories, Jini system of services like telephone directories in the user to find the information stored by service users is the telephone number. In other words, all need access Jini system services, we must find services that preserve the "telephone number." But many find more than a telephone directory services are the advantages, such as: Search service is a dynamic preservation of the "telephone directories" Moreover, system services can be in the "phonebook" and join in the initiative to remove their "phone numbers "and find services also fully support such a mechanism. And the content in the future, we will find more differences.
When the service to search registration services will have a notification event. System administrators can use the search service in the event callback mechanism to receive the notice. This help system administrators manage and maintain the system. And the service will be set up to provide its own user interface, the user interface as a service to the preservation of the properties of View services. Administrators can easily set up services, not everywhere busy for a variety of drivers and management software.
In the service during the period of service if they encounter problems should be brought to the attention of administrators, such as printing paper found that the shortage of services to an additional attribute to specify the problem. The results will be changes to the preservation View services. At this time, ditto above, the administrator uses the services provided by Search callback mechanism to the receipt of the notice. With such a powerful mechanism, greatly reducing the burden on the system administrator.
Discovery Protocol and accession agreement
In the network of services in the post and how to join the distributed Jini system, a Jini system of services, there are two important essential steps. Certainly the first step is to find the system's search services, this process is Discovery process, the agreement is found use agreement. The second step is to find themselves registered to the service, this process is Join process, describing this process is the agreement Join agreement. In a service after the completion of this two-step, to truly become a Jini system of a member. In order to accurately describe these two agreements, first tell us about the terminology used.
Mainframe. Have one or more of Java Virtual Machine and will be able to join the network hardware devices known as a mainframe group. Jini a group composed of a collection of services. Group name is arbitrary string, used to describe the nature of the group.
Tags: the core java technology