Abstract: A method for using dependency-based grouping to establish class identity comprises categorizing a plurality of classes into a set of class groups based at least in part on one or more dependencies between the classes, and generating metadata to be use for loading the classes, where the metadata includes a mapping between the set of class groups and the plurality of classes. The metadata may also include respective signatures for class groups and/or the individual classes. The method may also include validating, using at least a portion of the metadata, the identity of a particular version of a class of the plurality of classes, prior to loading the version for execution.

Abstract: Location-independent references include a live reference containing a location of a remote object and a universally unique identifier (UUID) which provides a unique global reference to that remote object. If a method call to the remote object using the live reference fails, the UUID is used to obtain a new reference to the remote object and the new reference is then used to make another method call. A new reference can be obtained from an identifier directory that contains a mapping between UUIDs and location-independent references. When a remote object is first created, or when a remote object is moved from one location to another, the remote object registers with any and all such directories that it can find in its environment. These registrations are leased; that is, if they are not occasionally refreshed by the remote object which registered them, they are dropped from the directory.

Abstract: An improved lookup service is provided that allows for the dynamic addition and deletion of services. This lookup service allows for the addition and deletion of services automatically, without user intervention. As a result, clients of the lookup service may continue using the lookup service and its associated services while the updates occur. Additionally, the lookup service provides a notification mechanism that can be used by clients to receive a notification when the lookup service is updated. By receiving such a notification, clients can avoid attempting to access a service that is no longer available and can make use of new services as soon as they are added to the lookup service.

Abstract: In accordance with the present invention a process is provided for allocating and deallocating resources in a distributed processing system having a requester platform and a server platform. The process involves receiving a request from the requestor platform referring to a system resource and specifying a requested lease period, permitting shared access to the system resource for a lease period, sending a return call to the requestor platform advising of the lease period, and deallocating the system resource when the lease period expires.