Advanced Remote Method Invocations

This set of vocabulary flashcards covers advanced Java RMI concepts including architectural layers, callback mechanisms, security protocols, and configuration tools.

Client Callback

An RMI feature where a client registers itself with a server so that the server may initiate communication with the client upon the occurrence of a specific event.

Stub Downloading

An RMI mechanism that allows stubs to be made available to the client dynamically via an HTTP server, permitting changes to remote methods without affecting the client program.

Security Manager

A component, such as the RMISecurityManager class, used to protect systems from malicious access by limiting privileges during remote method invocations.

Polling

A process where a client repeatedly contacts a passive server to check if an event has occurred, used in the absence of a callback mechanism.

Stub

A client-side object that supports the interface with the application program and interacts with the skeleton to access methods in the server object.

Skeleton

A server-side entity that maps the platform-independent layer to the platform-dependent transport layer and carries out remote reference transport.

Transport Layer

The layer in the Java RMI architecture that sets up, maintains, and shuts down connections while carrying out the transport protocol.

Remote Reference Layer

The architectural layer between the stub/skeleton layer and the transport layer that manages the transport of remote references.

RMI Registry

A directory service on the server host where clients look up interface objects to obtain remote references.

rmic

A command-line utility used to process a server class to generate the corresponding stub.class and skeleton.class files.

java.policy

A file used to specify access exceptions for the RMI security manager, such as permitting socket access to TCP ports like 1099 or 80.

SocketPermission

A specification within a java.policy file that allows network access to specific ports, such as ":1024-65535" for RMI registry access or ":80" for HTTP stub downloading.

UnicastRemoteObject

A class from which remote objects often inherit or use for exporting, allowing them to be accessible via remote method calls.

Codebase

A parameter specified when activating a server to define the location from which a stub file can be downloaded if stub downloading is desired.

HelloCallbackInterface

A remote interface used in callback applications that specifies a method, such as callMe, to be invoked by the server on the client.