Activity diagram is visually present a flow of control in system similar to a flow chart or data flow diagram. activity diagram usually used in business process modeling they can also describe the steps in use case diagram.
The diagram which has drawn below shows how the flow chart represent the flow of control in system:
Description and explanation of activity diagram:
Here in activity diagram show how the elements are used in diagram and how the activity begins and flow of control in system and how the flow end and now we are going explain what symbols are used to draw a activity diagram.
It indicates where the flow has to be start.
The arrows which is drawn above show the direction of work flow.
It indicates the unit of work is done by system and step in the process.
Decision box indicates the choice of flow here we can give more than one number of path decision
It indicates that flow of work is ended.
T he drawing elements which are drawn above diagram are:
CONNECTOR: Here in connector we can have multiple inputs and at a same time multiple out puts also.
FORK: Here in fork one path can splits in to two execute path.
JOINT : Here in joint two path combine in to one execute path
FORK AND JOINT: Between fork and joint we have number of path to control the pass all the path should execute.
BRANCH: Here in branch one flow splits in to multiple paths which are going to create a various activity.
MERGE: Here in merge multiple of paths are combined and execute one path
BRANCH AND MERGE: Between branch and merge we have number of paths for control to pass there for at least one path should execute.
NESTED LOOP: In this activity all the elements like fork and joint and branch and merge and controller and contain activities of series internally.
GUARD CONDITION:A condition is attached to the control flow when the condition is true and work flow may flow along the control flow.
A sequence diagram is unified modeling language diagram that illustrates the sequence of messages between objects in a interaction. A sequence diagram consists of group of objects that are represented by life line and the messages that they exchange over time interaction.
The sequence diagrams show the sequence of messages passed between objects, sequence diagram also show the control structure between objects
ELEMENTS OF SEQUENCE DIAGRAM:
Parallel and vertical lines different process or object that live simultaneously and horizontal arrows the messages exchanged between them. This allows the specification of simple run time scenario in a graphical manner.
TYPES OF DIAGRAM:
Sequence diagram also known as event diagram and there are two types of sequence diagram 1.uml diagram and 2.code based diagram.
BASIC SEQUENCE DIAGRAM NOTATIONS:
Benefits of sequence diagram
1.represents the details of uml use case
2.see how the objects and components interact with each other to complete the process
3.plan and understand the functionality of an existing scenario