Active Object System
Sung‐Woon Choi, Toshimi Minoura · 1991
An active object system is a transition-based object-oriented system suitable for the design of various concurrent systems. An AOS consists of a collection of interacting objects, where the behavior of each object is determined by the transition statements provided for the class of that object. A transition statement is a condition-action pair, an equational assignment statement, or an event routine. The transition statements provided for each object can access, besides the state of that object, the states of the other objects known to it through its interface variables. Interface variables are bound to objects when objects are instantiated so that desired connections among objects are established. The major benefit of the AOS approach is that an active system can be hierarchically composed from its active software components as if it were a hardware system.