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UML Diagrams
Zicomi Systems publishes some UML example diagrams online from the world famous UML dictionary.
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Version 2.5 Released
Zicomi Systems is delighted to announce that version 2.5 of Zicomi Mentor is released. With support for UML 2.0 and all thirteen UML diagrams
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Zicomi Systems' Director
speaks about the UML at Objects by Design - an informative interview
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Partner Programme
Zicom Systems is delighted to announce a new world wide partner programme, become a partner today.
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OMG Member
Zicom Systems is made a member of the OMG!
UML Element Description
State
State    
A state is a condition or phase, in the lifetime of a classifier instance, during which it can be observed for a finite amount of time and has a particular condition.
Transition
Transition    
A transition is an element relating two vertices in a state machine that represents the movement of an instance in the source state changing or "transitioning" into the instance in the second state. The transition takes place when an event occurs and the guard condition evaluates to TRUE
Initial
Initial    
An initial is a kind of pseudostate that represents the starting point in a region of a state machine. It has a single outgoing transition to the default state of the enclosing region, and has no incoming transitions. There can be one (and only one) initial state in any given region of a state machine. It is not itself a state but acts as a marker.
Final State
Final State    
A final state represents the last or "final" state of the enclosing composite state. There may be more than one final state at any level signifying that the composite state can end in different ways or conditions. When a final state is reached and there are no other enclosing states it means that the entire state machine has completed its transitions and no more transitions can occur.
Composite State
Composite State    
A composite state can contain other states and can be one of two types: simple or orthogonal. If it contains just one region it is termed a simple (non-orthogonal) composite state, if it contains two or more regions it is termed an orthogonal composite state. Each region contains a disjoint (mutually exclusive) set of vertices and transitions. Each region of a composite state can have one (and only one) initial pseudostate and any number of final states. An incoming transition that targets the boundary of a composite state is semantically equivalent to a transition to each initial pseudostates in every region of the composite state. A state is not complete until every region of the composite state is complete.
Composite State (HiddenDecomposition)
Composite State (HiddenDecomposition)    
A composite state with a hidden decomposition indicator icon is semantically equivalent to a composite state that explicitly displays its contents (other vertices and transitions). It is a useful notation or presentation option used to hide the detail of a composite state. See Composite State for details.
Submachine State
Submachine State    
A submachine state is semantically equivalent to a composite state but adds the mechanism for the submachine state to be reused in different contexts through the provision of entry and exit point connection references. Entry and exit to the submachine state is always through the connection point references which are part of the submachine state definition. A state is not permitted to have both regions and submachine states.
Choice
Choice    
A choice is a pseudostate that acts a decision point. It has a single incoming transition and two or more outgoing transitions one (and only one) of which will fire as a result of the firing of the incoming transition. Each outgoing transition is guarded by a condition, which must evaluate to "TRUE" or "FALSE". A transition will fire if and only if its guard evaluates to "TRUE".
Comment (Note)
Comment (Note)    
A comment can contain textual information or graphical symbols that add additional information to a diagram or model. The information can take many forms from very formal, in the case of constraints, to conversational, in the case of working notes. Comments can be placed anywhere in a model or diagram, and simply by their proximity and alignment; they can be applicable to one or more elements. They may also be attached either to one or more elements by a comment attaching line.
Comment (Note) Attaching Line
Comment (Note) Attaching Line    
A comment attaching line is a dashed line that is used to attach a comment (note) to a model element in a diagram. The comment (note) attaching line is not a UML relationship and has no semantics beyond signifying that the contents of a comment apply to the model element it is attached to. A comment may be attached to any number of model elements or may exist in isolation and by placement in proximity to one or more model elements signify that it applies to those elements.
Region
Region    
A region is a part of a state machine or composite state. It contains (encloses) vertices and transitions. It can have one (and only one) initial pseudostate and any number of final states. A composite state with one region is called a non-orthogonal (simple) composite state and one with two or more regions is called an orthogonal state.
Entry Point
Entry Point    
An entry point is a pseudostate that marks the point of entry to the region in a state machine in which it is enclosed. It has a single outgoing transition to a vertex in the same region. An entry point can only be defined for the top most regions of a state machine and not for regions owned by other regions. Each topmost region of a state machine can contain one (and only one) entry point.
Exit Point
Exit Point    
An exit point is a pseudostate that marks the point of exit from the region in a state machine in which it is enclosed. It may have one or more incoming transitions from vertices in the same region. An exit point can only be defined for the top most regions of a state machine and not for regions owned by other regions. Each topmost region of a state machine can contain any number of exit points.
Fork (Vertical)
Fork (Vertical)    
A fork is a pseudostate that acts to split a single incoming transition into two or more concurrent outgoing transitions. All of the outgoing transitions fire at the same time.
Fork (Horizontal)
Fork (Horizontal)    
A fork can be orientated horizontally or vertically. Both orientations have exactly the same semantics the difference is simply that when transition are parallel to the x axis a vertically orientated fork is required whereas when transitions are parallel to the y axis a horizontally orientated fork is required.
Join (Vertical)
Join (Vertical)    
A join is a kind of pseudostate that re-unites two or more incoming transitions. All of the incoming transitions must have fired before the outgoing transition will fire.
Join (Horizontal)
Join (Horizontal)    
A join can be orientated horizontally or vertically. Both orientations have exactly the same semantics; the difference is simply that when transitions are parallel to the x-axis a vertically orientated join is required whereas when transitions are parallel to the y-axis a horizontally orientated join is required.
Terminate
Terminate    
A terminate is a kind of pseudostate that stops the execution of the enclosing state machine. It can have one or more incoming flows but no outgoing flows. While a final state signifies that execution within the enclosing region is complete, a terminate ends the execution of the entire state machine including all regions contained within the machine.
Junction
Junction    
A junction is a kind of pseudostate that is used to merge and (or) split one or more transitions between states creating complex paths. They can take one or more incoming transitions and have one or more outgoing transitions. The do not create concurrent transitions but their result is the firing of a single outgoing transition. The outgoing transitions are typically guarded and these conditions are evaluated statically.
Shallow History
Shallow History    
A shallow history is a kind of pseudostate that acts as marker or placeholder in a composite state. It represents the state or condition of the modeled element at the time it was last exited. It is not a state itself but a diagrammatic representation or marker for the "condition" of the composite state down to a single level, at the time it was last exited.
Deep History
Deep History    
A deep history is a kind of pseudostate that acts as a marker or placeholder. It represents the most recent active substate of the containing composite state, and the substates of that substate. It is not a state itself but a diagrammatic representation or marker for the "condition" of the composite state down to any level, at the time it was last exited.
Entry Connection Point Reference
Entry Connection Point Reference    
An entry connection point reference represents the entry point to a submachine state. It provides a target for a transition to a submachine state and is the only way that a submachine state can be referenced. A submachine state may have any number of entry connection point references and these represent entry point pseudostates defined in the submachine state.
Exit Connection Point Reference
Exit Connection Point Reference    
An exit connection point reference represents the exit point to a submachine state. It provides a source for a transition leaving a submachine state and is the only way that a submachine state can be referenced. A submachine state may have any number of exit connection point references and these represent exit point pseudostates defined in the submachine state.
Sending Signal
Sending Signal    
A sending signal is a representation of an action that sends a signal. The action has one incoming transition and one outgoing transition. The signal is always sent asynchronously; the object receiving the signal may be shown, with a dashed arrow drawn from the pentagon to the object. The signal signature is written inside the pentagon.
Receipt Signal
Receipt Signal    
A receipt signal is a type of state that represents the receipt of a signal on an activity diagram. The state does not have actions or internal transitions. It simply represents the receipt of the signal, which causes the outgoing transition to fire. A dashed arrow may be drawn from the object sending the signal to the receipt signal. The signal signature is written inside the pentagon.
Generalization
Generalization    
Generalization is a relationship of classification between a more general element (parent) and a more specific element (child). The head of the arrow is attached to the "parent" and the tail is attached to the "child". It is a taxonomic relationship that can exist between a number of types of UML elements including classifiers and associations.
Unified Modeling Language and UML are either registered

trademarks or trademarks of Object Management Group, Inc. in the

United States and/or other countries.