UML Timing Diagram

 Timing Diagram

The timing diagrams are the specialized behavioral modeling diagram. It concentrates on the various timing constraints. These diagrams can be created when you require learning how the objects collaborate with each other over a specific time period.

The timing diagram concentrates on conditions modifying and between the lifelines along the precarious time axis. These diagrams define the nature of individual classifiers and classifier’s interactions. It concentrates on the time of event occurrence producing modifications in the lifeline’s modeled conditions.

Time moves on the x-axis from the left axis to the right axis, along with distinct elements of a system that cooperate with each other over the y-axis. These diagrams illustrate how long every process step takes. We can use these steps to determine which process steps need time and also to search for areas for development.

It comprises of a waveform or graph that portrays the lifeline’s state at a particular time moment. It represents how various conditions are modified between and inside the lifelines by the side of a definite time axis. The waveform depicts the flow between some software plans at numerous time instances.

Basic Approaches of the Timing Diagram

Some of the basic approaches of the timing diagram are listed and discussed below:

Lifelines: A lifeline depicts an individual component within the interaction. It serves as a single entity, which is a subset of an interaction. It can be displayed by the name of the classifier that it portrays. The lifelines are positioned inside a diagram frame or a swim lane.

Condition or State Timeline

These timelines are continuous. The condition and state timelines are used to represent the density and temperature where various entities tolerate a continuous state variation. The timing diagram shows the cooperation of the attributes and classifier’s state. Also, it shows a few testable conditions, which is a distinct classifier’s value.   

Duration Constraint

A duration constraint is an interval constraint, which invokes a duration interval. A duration constraint linguistic is acquired from constraints. It can be used to identify that a constraint is contended for a span or not. When a negative trace describes the disrupted constraints, it specifies that the system is broken down. The graphical association among construct and the duration interval may illustrate the duration constraint.

Time Constraint

A timing constraint is also a constraint of an interval, which invokes towards a time interval. It can be used to portray that a constraint is a contends or not, as it is a time expression. The constraints allocate the semantic of time constraints.

When a negative trace describes the disrupted constraints, it specifies that the system is broke down.  The graphical association illustrates a timing diagram among a construct and an interval of time that it constraints. A tiny line between the occurrence specification and the time interval may represent the graphical association.

Destruction Occurrence

A destruction occurrence invokes a message occurrence that illustrates an instance of destruction is described by the lifeline. It is served at the end of the timeline by a cross. Afterward, it may destruct the other objects retained by this object’s composition.

Timing Diagram at a Peek

Representation of state Timeline

It represents the modifications through one state to other states by the change within in lifeline level. The timeline executes parallel towards that state when an object is a disposed state. The state change occurs as a change from one level to other levels vertically. Various cause of the modification can be the following:

• Time passage
• Condition inside the system
• Message receipt
• An event that can cause a change.

Representation of Value Lifeline

It represents the object state among two lines horizontally, that pass each time each other the changes of the state.

Example of Timing Diagram

Water Cycle

This example represents a simplified form of a water cycle. As the timing diagrams concentrates on how every step takes, but not on a system itself. We could assume of this like the diagram of distinct phases that the water bead cycles through. The viewers could surely determine the places for improvement, if it was a process of manufacturing. The timing diagram is a strong tool for designing a system as effective and simple as possible.

 Car Park

The timing diagram must be persistent with the compatible state diagram and sequence diagram. For doing this, we can add states to the lifeline for every object inside the sequence diagram. Then we can obtain the reciprocal timing diagram much easier. It can be done by checking out the information passing among the objects opposed to states connected inside the lifeline.

The various segments of the timing diagram introduce the sequence diagram’s contents. The following diagram is an example of a car park, which shows a reciprocal timing diagram.

Advantages of Timing Diagram

• It keeps track of every change that occurs in the system.
• It can be used to implement forward engineering and reverse engineering.
• It portrays the object state at a specific period of time.
• Whenever the information has been transferred between objects, the timing diagram focuses on that specific time.
• It describes an object’s processing time in detail.
• It explains the graphical representation of the lifeline state.
• These diagrams contain various notations that can be helpful to clarify a transition state between two lifelines.
• The timing diagram can be read from left to right, as a lifeline is named on the edge’s left side.
• It also describes how the object bears modifications in its form over its lifeline.
• It is occupied with embedded and distributed systems.

Disadvantages of Timing Diagram

• The timing diagrams are difficult to understand and maintain.