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| 3 | <title>State machine glossary</title><link rel="stylesheet" href="boostbook.css" type="text/css"><meta name="generator" content="DocBook XSL-NS Stylesheets V1.75.2"><link rel="home" href="index.html" title="Meta State Machine (MSM)"><link rel="up" href="ch02.html" title="Chapter 2. UML Short Guide"><link rel="prev" href="ch02s03.html" title="Added concepts"><link rel="next" href="ch03.html" title="Chapter 3. Tutorial"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">State machine glossary</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch02s03.html">Prev</a> </td><th width="60%" align="center">Chapter 2. UML Short Guide</th><td width="20%" align="right"> <a accesskey="n" href="ch03.html">Next</a></td></tr></table><hr></div><div class="sect1" title="State machine glossary"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="d0e264"></a>State machine glossary</h2></div></div></div><p> | |
| 4 | </p><div class="itemizedlist"><ul class="itemizedlist" type="disc"><li class="listitem"><p>state machine: the life cycle of a thing. It is made of states, | |
| 5 | regions, transitions and processes incoming events.</p></li><li class="listitem"><p>state: a stage in the life cycle of a state machine. A state (like | |
| 6 | a submachine) can have an entry and exit behaviors.</p></li><li class="listitem"><p>event: an incident provoking (or not) a reaction of the state | |
| 7 | machine</p></li><li class="listitem"><p>transition: a specification of how a state machine reacts to an | |
| 8 | event. It specifies a source state, the event triggering the | |
| 9 | transition, the target state (which will become the newly active | |
| 10 | state if the transition is triggered), guard and actions.</p></li><li class="listitem"><p>action: an operation executed during the triggering of the | |
| 11 | transition.</p></li><li class="listitem"><p>guard: a boolean operation being able to prevent the triggering of | |
| 12 | a transition which would otherwise fire.</p></li><li class="listitem"><p>transition table: representation of a state machine. A state | |
| 13 | machine diagram is a graphical, but incomplete representation of the | |
| 14 | same model. A transition table, on the other hand, is a complete | |
| 15 | representation.</p></li><li class="listitem"><p>initial state: The state in which the state machine starts. Having | |
| 16 | several orthogonal regions means having as many initial | |
| 17 | states.</p></li><li class="listitem"><p>submachine: A submachine is a state machine inserted as a state in | |
| 18 | another state machine and can be found several times in a same state | |
| 19 | machine.</p></li><li class="listitem"><p>orthogonal regions: (logical) parallel flow of execution of a | |
| 20 | state machine. Every region of a state machine gets a chance to | |
| 21 | process an incoming event.</p></li><li class="listitem"><p>terminate pseudo-state: when this state becomes active, it | |
| 22 | terminates the execution of the whole state machine. MSM does not | |
| 23 | destroy the state machine as required by the UML standard, however, | |
| 24 | which lets you keep all the state machine's data.</p></li><li class="listitem"><p>entry/exit pseudo state: defined for submachines and are defined | |
| 25 | as a connection between a transition outside of the submachine and a | |
| 26 | transition inside the submachine. It is a way to enter or leave a | |
| 27 | submachine through a predefined point.</p></li><li class="listitem"><p>fork: a fork allows explicit entry into several orthogonal regions | |
| 28 | of a submachine.</p></li><li class="listitem"><p>history: a history is a way to remember the active state of a | |
| 29 | submachine so that the submachine can proceed in its last active | |
| 30 | state next time it becomes active.</p></li><li class="listitem"><p>completion events (also called completion/anonymous transitions): | |
| 31 | when a transition has no named event triggering it, it automatically | |
| 32 | fires when the source state is active, unless a guard forbids | |
| 33 | it.</p></li><li class="listitem"><p>transition conflict: a conflict is present if for a given source | |
| 34 | state and incoming event, several transitions are possible. UML | |
| 35 | specifies that guard conditions have to solve the conflict.</p></li><li class="listitem"><p>internal transitions: transition from a state to itself without | |
| 36 | having exit and entry actions being called.</p></li></ul></div><p> | |
| 37 | </p></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch02s03.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch02.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ch03.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Added concepts </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 3. Tutorial</td></tr></table></div></body></html> |