In object-oriented techniques, the interaction between objects is done by the transmission of inter-object messages. This concept is used in the four dynamic models of UML. Typically, a message delivery is completed when an object calls an operation in another object. When the operation is executed, the control returns to the caller. Objects cooperate with each other, and constantly changing its own state based on the results of communication in their life cycle.
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Dynamic modeling mechanism of standard modeling language UML
