31081831 Airline Reservation System

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DECCAN COLLAGE OF ENGINEERING &

TECHNOLOGY

Dar-us-Salam, Hyderabad -500 001.

DEPARTMENT OF INFORMATIN TECHNOLOGY

OBJECT ORIENTED SYSTEM DEVELOPMENT LAB

CERTIFICATEThis is to certify that

Of B.E. (III/IV) 2nd SEMESTER, IT branch has successfully

completed the MINI PROJECT work during the academic year 2010.

H.O.D Internal Examiner External

INDEX

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S.no Contents Page no

1 Abstract 32 Problem statement 4

3 Proposed system 5

4 SRS of ATM 6

5 About UML 12

6 CLASS DIAGRAM 47

7 USE CASE DIAGRAM 48

8 SEQUENCE DIAGRAM 51

9 COLLABORATION DIAGRAM 52

10 ACTIVITY DIAGRAM 53

11 SWIMLANE DIAGRAM 56

12 STATE CHART DIAGRAM 57

13 COMPONENT DIAGRAM 58

14 DEPLOYMENT DIAGRAM 60

ABSTRACT

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The online reservation system is basically derived from the GDS (global distribution

system) also known as CRS (computer reservation system). The online reservation

system has its database centrally located which is accessed through an Application

Programming Interface (API).With the invent of online reservation system the

traveller and the airline got the freedom to book a seat anywhere at anytime at their

conveniance. The traveller can book a ticket at a click of a mouse saving the time and

money for the traveller. It has also become a hassle free transaction for both the airline

and the travller. The online reservation system involves three main actors the

database , online operator and a databse scheduler. The database scheduler updates the

database , te online operator accepts and confirms the booking and updates the

database.

PROBLEM STATEMENT

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The existing airline reservation system has many shortcomings associated with it. In

the existing system airlines used to set flight reservation levels higher than seatingcapacity to compensate for passenger cancellations and no-shows accounting to

overbooking in the system. If a traveller had to make / cancel reservation he had to

visit either the airline or travel agent frequently to do so thus wasting time and money

for all. In the existing system due to non-availability of a central server the airline and

the agents suffered unwanted delays in bookings and payments. In the existing system

integration of different airlines on a single platforms was not met. With the advent of

the online reservation system these flaws can be overcome.

Proposed statement

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The new online reservation system maintains the database centrally giving the clients

the information required from anywhere in the world whenever required. This system

requires the use of an API (Application Programming Interface) through which it

extracts the data from a central database. The central database monitors all the data

changes that are made at the client side to it and updates it automatically.

Through online reservation system customer is able to book & purchase the ticket

from his home/office conveniently it doesnt require the customer to go to the airline

or an agent to purchase a ticket thus saving time & money for the customer and an

airline/agent. As the information is stored centrally the customer never loses his ticket

as in the existing system.

SOFTWARE REQUIREMENTS SPECIFICATIONAIRLINE RESERVATION SYSTEM

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1. INTRODUCTION

1.1. PURPOSE

The main purpose of this software is to reduce the manual errors involved in

the airline reservation process and make it convenient for the customers to book the

flights as when they require such that they can utilize this software to make

reservations, modify reservations or cancel a particular reservation.

1.2 SCOPE

The name of the software is AIRLINE RESERVATION SYSTEM. This

software provides options for viewing different flights available with different timingsfor a particular date and provides customers with the facility to book a ticket, modify

or cancel a particular reservation but it does not provide the customers with details of

cost of the ticket and it does not allow the customer to modify a particular part of his

reservation and he/she can modify all his details.

1.3 DEFINITIONS, ACRONYMS AND ABBREVIATIONS

ARS-Airline Reservation System

LAN-Local Area Network

GUI-Graphical User InterfaceOS-Operating System

RAM-Random Access Memory

MB-Mega Bytes

GB-Giga Bytes

Mbps-Mega bits per second

HDD-Hard Disk Drive

1.4 REFERENCES

en.wikipedia.org/wiki/Airline_Reservations_System

www.fyxm.net/airline-reservation-system-project-54574.htm

www.ece.cmu.edu/~ece841/team2/index.html

1.5 OVERVIEW

The rest of the document deals about all the main features of this software each will its

purpose and its main functions. It also gives details about the interface with other

products and related functionality of each product.

2. OVERALL DESCRIPTION

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2.1 PRODUCT PERSPECTIVE

The ARS software is an independent application. It is a self-contained product. The

system interfaces, user interfaces and hardware interfaces related with this software

are defined as follows.

2.1.1 System InterfacesThe client systems should be able to share the data available in the data base through

the network connection.

2.1.2 User InterfacesThe screen formats and menu structure should be in such a way that even have users

will find it easy to use. The product must be use-friendly and very inter-active. The

functionality provided by the system like displaying error messages should adapt itself

to the different users of the software.

2.1.3 Hardware InterfacesNil

2.1.4 Software InterfacesName of the language: Visual Basics

2.1.5 Communication Interfaces

There is an LAN used for communication among the different client systems to beused.

2.1.6 Memory ConstraintsThe system would require disk space of 10 GB and a 256 MB HDD and 64 MB RAM

for client systems.

2.1.7 OperationThe users can first make a reservation in a particular flight for a particular date and

time. The system provides the customer with a pin code which gives him access to

either make any changes in his reservation or cancel a reservation. These must also be

back up of data to enable any easy recovery from any features.

2.1.8 Site Adaptive RequirementsThe ARS software is an independent and self-contained product and no

modification are required to adapt to a particular installation.

2.2 PRODUCT FUNCTIONS

The major functions include

Providing flight details

Flight bookings for a particular destination, date and time and also providingwith a pin code.

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Allowing the customer to modify or cancel his reservation provided the correct

pin code is given.

Displaying a report of the number of people flying in a particular flight.

2.3 USER CHARACTERISTICS

No technical experience is required basic knowledge of handling system is sufficient.

2.4 CONSTRAINTS

Regulatory policies: It is a mandatory that no text book must be left empty or

contains insufficient data.

Hardware limitations: There must be a 64 MB on board memory

Control functions: The software must be very user-friendly and displayappropriate error messages.

Interfaces to other applications: Not applicable.

Parallel operations: It must support many users simultaneously.

Reliability requirements: Data redundancy and use of special/blank characters

must be avoided.

Safety/security considerations: The application must be exited always

normally.

Higher order language requirements: VB

2.5 ASSUMPTIONS AND DEPENDENCIES

It is assumed that the details of the cost of ticket are already known to the customer.

Future changes like providing different types of flights with different classes like

business class, economic class will allow the customers to benefit from one facility.

2.6 APPORTIONING OF REQUIREMENTS

The necessity of providing options to customer to choose their seat or to choose for

economic or business class can be delayed until future versions of the software are

developed.

3. SPECIFIC REQUIREMENTS

3.2 SOFTWARE PRODUCT FEATURES

3.2.1 FEATURE 1The ability of the software is to provide the details of the flights available and allow

the customers to choose a particular destination and make a reservation.

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3.2.1.1 PURPOSEThe purpose of this is to enable the users to view the different flights available

so as to make it convenient for him to make a reservation.

3.2.1.2 STIMULUS/RESPONSEOnce the user chooses the particular option, the web pages corresponding tothat are to be displayed on the screen i.e., it will display the different flights

available to their respective destinations and allow the customer to book a

ticket.

3.2.1.3 ASSOCIATED FUNCTIONAL REQUIREMENTS

3.2.1.3.1 FUNCTIONAL REQUIREMENTSOnce the user makes a reservation, he must be provided with a pin

code.

3.2.1.3.1.1 INTRODUCTIONThe user must be provided with the required information within 10

seconds.

3.2.1.3.1.2 INPUTSThe user must enter the destination with date and timings and must

make reservation by giving his personal details like name, address, age,

gender, nationality.

3.2.1.3.1.3 PROCESSINGRecognizing the correct details are entered that a message is displayed

confirming his reservation and displays the pin code.

3.2.2 FEATURE 2The software allows the user to modify an already existing reservation made

by the customer if in case there are any changes that are to be modified in the

reservations of the ticket.

3.2.2.1 PURPOSE

The purpose is to allow the customer to make any changes in his personaldetails or flight booking details.

3.2.2.2 STIMULUS/RESPONSEOnce the user requests for changing his reservation, it must be displayed on the

screen prompting the customer to enter his pin code.

3.2.2.3 ASSOCIATED FUNCTIONALITY REQUIREMENTS

3.2.2.3.1 FUNCTIONAL REQUIREMENTS

If the pin code provided by the customer does not match, then wouldnotify the person by displaying error messages.

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3.2.2.3.1.1 INTRODUCTIONThe system will allow the customer to modify his reservation provided

correct pin code has been entered by him.

3.2.2.3.1.2 INPUTThe user should enter his pin code which gives him access to modify

his reservation.

3.2.2.3.1.3 PROCESSINGThe pin code is processed and checked for his validity. If it is correct

then the user can modify his reservation else an error message will be

displayed asking the user to enter the correct pin code number.

3.2.2.3.1.4 OUTPUT

Given the correct pin code, the user can now modify his reservation. Anew pin code will be generated for the customers.

3.2.3 FEATURE 3The software allows the user to cancel an already existing reservation made by the

customer who has booked the ticket.

3.2.3.1 PURPOSEThe purpose is to allow the customer to cancel his reservation if not required.

3.2.3.1 STIMULUS/RESPONSEOnce the user requests for canceling his reservation, it must be displayed on

the screen prompting the customer to enter his pin code.

3.2.3.3 ASSOCIATED FUNCTIONAL REQUIREMENTS

3.2.3.3.1 FUNCTIONAL REQUIREMENTSIf the pin code provided by the customer does not match, then it would

notify the person by displaying error messages.

3.2.3.3.1.1 INTRODUCTIONThe system will allow the customer to cancel his reservation provided

correct pin code has been entered by the customer.

3.2.3.3.1.2 INPUTThe user should enter his pin code which gives him access to cancel his

reservation.

3.2.3.3.1.3 PROCESSING

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The pin code is processed and checked for its validity. If it is correct,

then the user can cancel his reservation else an error message will be

displayed asking the user to enter the correct pin code number.

3.2.3.3.1.4 OUTPUTGiven the correct pin code, the user can now cancel his reservation.

UNIFIED MODELING LANGUAGE

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Introduction:

The unified modeling language(UML)is a standard language for writing software blue

prints.

The UML is a language for

Visualizing

Specifying

Constructing

Documenting

The artifacts of a software system:

UML is a language that provides vocabulary and the rules for combing words in that

vocabulary for the purpose of communication.

A modeling language is a language whose vocabulary and rules focus on the

concept and physical representation of a system.

Vocabulary and rules of a language tell us how to create

and real well formed models, but they dont tell you what

model you should create and when should create them.

VISUALIZING

The UML is more than just a bunch of graphical symbols. In UML each symbol has

well defined semantics. In this manner one developer can write a model in the UML

and another developer or even another tools can interpret the model unambiguously.

SPECIFYING

UML is used fro specifying means building models that are precise, unambiguous and

complete.

UML addresses the specification of all the important analysis, design and

implementation decisions that must be made in developing and deploying a software

intensive system.

CONSTRUCTING

UML is not a visual programming language but its models can be directly connected

to a variety of programming languages.

This means that it is possible to map from a model in the

UML to a programming language such as java, c++ or Visual Basic or even to tables

in a relational database or the persistent store of an object-oriented database.

This mapping permits forward engineering. The

generation of code from a UML model into a programming language.

The reverse engineering is also possible you can

reconstruct a model from an implementation back into the UML.

DOCUMENTING

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UML is a language for Documenting. A software organization produces all sorts of

artifacts in addition to raw executable code. These artifacts include

Requirements,Architecture,Design,Sourcecode,Project plans,Test,Prototype,Release.

Such artifacts are not only the deliverables of a project,they are also critical in

controlling,measuring and communicating about a system during its development and

after its deployment.

Conceptual model of the UML:

To understand the UML, we need to form a conceptual model of the language and this

requires learning three major elements.

The UML Basic Building Blocks.

The Rules that direct how those building blocks may be put together.

Some common mechanisms that apply throughout the UML.

As UML describes the real time systems it is very important to make a conceptual

model and then proceed gradually. Conceptual model of UML can be mastered bylearning the following three major elements:

UML building blocks

Rules to connect the building blocks

Common mechanisms of UML

This chapter describes all the UML building blocks. The building blocks of UML can

be defined as:

Things Relationships

Diagrams

Things:

Things are the most important building blocks of UML. Things can be:

Structural

Behavioral

Grouping

Annotational

Structural things:The Structural things define the static part of the model. They represent physical and

conceptual elements. Following are the brief descriptions of the structural things.

Class:

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Class represents set of objects having similar responsibilities.

Interface:

Interface defines a set of operations which specify the responsibility of a class.

Collaboration:

Collaboration defines interaction between elements.

Use case:

Use case represents a set of actions performed by a system for a specific goal.

Component:

Component describes physical part of a system.

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Node:

A node can be defined as a physical element that exists at run time.

Behavioral things:

Abehavioral thing consists of the dynamic parts of UML models. Following are the

behavioral things:

Interaction:

Interaction is defined as a behavior that consists of a group of messages exchanged

among elements to accomplish a specific task.

State machine:

State machine is useful when the state of an object in its life cycle is important. It

defines the sequence of states an object goes through in response to events. Events are

external factors responsible for state change.

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Grouping things:Grouping things can be defined as a mechanism to group elements of a UML model

together. There is only one grouping thing available.

Package:

Package is the only one grouping thing available for gathering structural and

behavioral things.

Annotational things:

Annotational things can be defined as a mechanism to capture remarks, descriptions,

and comments of UML model elements. Note is the only one Annotational thingavailable.

Note:

A note is used to render comments, constraints etc of an UML element.

RELATIONSHIP IN UML

Relationship is another most important building block of UML. It shows how

elements are associated with each other and this association describes the functionality

of an application.

There are four kinds of relationships available.

Dependency:

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Dependency is a relationship between two things in which change in one element also

affects the other one.

Association:

Association is basically a set of links that connects elements of an UML model. It also

describes how many objects are taking part in that relationship.

Generalization:

Generalization can be defined as a relationship which connects a specialized element

with a generalized element. It basically describes inheritance relationship in the world

of objects.

Realization:

Realization can be defined as a relationship in which two elements are connected. One

element describes some responsibility which is not implemented and the other one

implements them. This relationship exists in case of interfaces.

UML DIAGRAMS:

UML diagrams are the ultimate output of the entire discussion. All the elements,

relationships are used to make a complete UML diagram and the diagram represents a

system.

The visual effect of the UML diagram is the most important part of the entire process.

All the other elements are used to make it a complete one.

UML includes the following nine diagrams and the details are described in the

following chapters.

Class diagram

Object diagram

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Use case diagram

Sequence diagram

Collaboration diagram

Activity diagram

Statechart diagram

Deployment diagram

Component diagram

We would discuss all these diagrams in subsequent chapters of this tutorial.

ARCHITECTURE OF UML

Any real world system is used by different users. The users can be developers, testers,business people, analysts and many more. So before designing a system the

architecture is made with different perspectives in mind. The most important part is to

visualize the system from different viewer.s perspective. The better we understand the

better we make the system.

UML plays an important role in defining different perspectives of a system. These

perspectives are:

Design

Implementation

Process

Deployment

And the centre is the Use Case view which connects all these four. A Use case

represents the functionality of the system. So the other perspectives are connected

with use case.

Design of a system consists of classes, interfaces and collaboration. UML provides

class diagram, object diagram to support this.

Implementation defines the components assembled together to make a complete

physical system. UML component diagram is used to support implementationperspective.

Process defines the flow of the system. So the same elements as used inDesign are

also used to support this perspective.

Deployment represents the physical nodes of the system that forms the hardware.

UML deployment diagram is used to support this perspective.

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CLASS DIAGRAMOverview:

The class diagram is a static diagram. It represents the static view of an application.

Class diagram is not only used for visualizing, describing and documenting different

aspects of a system but also for constructing executable code of the software

application.

The class diagram describes the attributes and operations of a class and also the

constraints imposed on the system. The class diagrams are widely used in the

modelling of object oriented systems because they are the only UML diagrams which

can be mapped directly with object oriented languages.

The class diagram shows a collection of classes, interfaces, associations,

collaborations and constraints. It is also known as astructural diagram.

Purpose:

The purpose of the class diagram is to model the static view of an application. The

class diagrams are the only diagrams which can be directly mapped with object

oriented languages and thus widely used at the time of construction.

The UML diagrams like activity diagram, sequence diagram can only give the

sequence flow of the application but class diagram is a bit different. So it is the most

popular UML diagram in the coder community.

So the purpose of the class diagram can be summarized as:

Analysis and design of the static view of an application.

Describe responsibilities of a system.

Base for component and deployment diagrams.

Forward and reverse engineering.

How to draw Class Diagram?Class diagrams are the most popular UML diagrams used for construction of software

applications. So it is very important to learn the drawing procedure of class diagram.

Class diagrams have lot of properties to consider while drawing but here the diagram

will be considered from a top level view.Class diagram is basically a graphical representation of the static view of the system

and represents different aspects of the application. So a collection of class diagrams

represent the whole system.

The following points should be remembered while drawing a class diagram:

The name of the class diagram should be meaningful to describe the aspect of the

system.

Each element and their relationships should be identified in advance.

Responsibility (attributes and methods) of each class should be clearly identified.

For each class minimum number of properties should be specified. Because

unnecessary properties will make the diagram complicated.

Use notes when ever required to describe some aspect of the diagram. Because at the

end of the drawing it should be understandable to the developer/coder.

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Finally, before making the final version, the diagram should be drawn on plain paper

and rework as many times as possible to make it correct.

Now the following diagram is an example of an Order System of an application. So itdescribes a particular aspect of the entire application.

First of all Orderand Customerare identified as the two elements of the system and

they have a one to many relationship because a customer can have multiple orders.We would keep Orderclass is an abstract class and it has two concrete classes

(inheritance relationship) SpecialOrderandNormalOrder.The two inherited classes have all the properties as the Orderclass. In addition they

have additional functions like dispatch () and receive ().So the following class diagram has been drawn considering all the points mentioned

above:

Where to use Class Diagrams?

Class diagram is a static diagram and it is used to model static view of a system. The

static view describes the vocabulary of the system.

Class diagram is also considered as the foundation for component and deployment

diagrams. Class diagrams are not only used to visualize the static view of the system

but they are also used to construct the executable code for forward and reverseengineering of any system.

Generally UML diagrams are not directly mapped with any object oriented

programming languages but the class diagram is an exception.

Class diagram clearly shows the mapping with object oriented languages like Java, C+

+ etc. So from practical experience class diagram is generally used for construction

purpose.

So in a brief, class diagrams are used for:

Describing the static view of the system.

Showing the collaboration among the elements of the static view.

Describing the functionalities performed by the system.

Construction of software applications using object oriented languages.

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OBJECT DIAGRAM

Object diagram shows a set of objects and there relationships.Object diagram

represents static snapshot of instances of the things found in class diagram.

These diagrams addresses static design view or static process view of a system.

USE CASE DIAGRAM

Overview:

To model a system the most important aspect is to capture the dynamic behaviour. To

clarify a bit in details, dynamic behaviourmeans the behaviour of the system when it

is running /operating.So only static behaviour is not sufficient to model a system rather dynamic behaviour

is more important than static behaviour. In UML there are five diagrams available to

model dynamic nature and use case diagram is one of them. Now as we have to

discuss that the use case diagram is dynamic in nature there should be some internal or

external factors for making the interaction.

These internal and external agents are known as actors. So use case diagrams are

consists of actors, use cases and their relationships. The diagram is used to model the

system/subsystem of an application. A single use case diagram captures a particular

functionality of a system.

So to model the entire system numbers of use case diagrams are used.

Purpose:

The purpose of use case diagram is to capture the dynamic aspect of a system. But this

definition is too generic to describe the purpose.

Because other four diagrams (activity, sequence, collaboration and Statechart) are also

having the same purpose. So we will look into some specific purpose which will

distinguish it from other four diagrams.

Use case diagrams are used to gather the requirements of a system including internal

and external influences. These requirements are mostly design requirements. So when

a system is analyzed to gather its functionalities use cases are prepared and actors are

identified.Now when the initial task is complete use case diagrams are modelled to present the

outside view.

So in brief, the purposes of use case diagrams can be as follows:

Used to gather requirements of a system.

Used to get an outside view of a system.

Identify external and internal factors influencing the system.

Show the interacting among the requirements are actors.

How to draw Component Diagram?

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Use case diagrams are considered for high level requirement analysis of a system. So

when the requirements of a system are analyzed the functionalities are captured in use

cases.

So we can say that uses cases are nothing but the system functionalities written in an

organized manner. Now the second things which are relevant to the use cases are the

actors. Actors can be defined as something that interacts with the system.The actors can be human user, some internal applications or may be some external

applications. So in a brief when we are planning to draw an use case diagram we

should have the following items identified.

Functionalities to be represented as an use case

Actors

Relationships among the use cases and actors.

Use case diagrams are drawn to capture the functional requirements of a system. So

after identifying the above items we have to follow the following guidelines to draw

an efficient use case diagram.The name of a use case is very important. So the name should be chosen in such a way

so that it can identify the functionalities performed.

Give a suitable name for actors.

Show relationships and dependencies clearly in the diagram.

Do not try to include all types of relationships. Because the main purpose of the

diagram is to identify requirements.

Use note when ever required to clarify some important points.

The following is a sample use case diagram representing the order management

system. So if we look into the diagram then we will find three use cases (Order,

SpecialOrder and NormalOrder) and one actor which is customer.

The SpecialOrderandNormalOrderuse cases are extended from Orderuse case. Sothey have extends relationship. Another important point is to identify the system

boundary which is shown in the picture. The actorCustomerlies outside the system asit is an external user of the system.

INTERACTION DIAGRAM

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We have two types of interaction diagrams in UML. One is sequence diagram and the

other is a collaboration diagram. The sequence diagram captures the time sequence of

message flow from one object to another and the collaboration diagram describes the

organization of objects in a system taking part in the message flow.

So the following things are to identified clearly before drawing the interaction

diagram:

Objects taking part in the interaction.

Message flows among the objects.

The sequence in which the messages are flowing.

Object organization.

Following are two interaction diagrams modeling order management system. The first

diagram is a sequence diagram and the second is a collaboration diagram.

The Sequence Diagram:

The sequence diagram is having four objects (Customer, Order, SpecialOrder and

NormalOrder).

The following diagram has shown the message sequence forSpecialOrderobject and

the same can be used in case ofNormalOrderobject. Now it is important tounderstand the time sequence of message flows. The message flow is nothing but a

method call of an object.

The first call issendOrder () which is a method ofOrderobject. The next call is

confirm () which is a method ofSpecialOrderobject and the last call isDispatch ()which is a method ofSpecialOrderobject. So here the diagram is mainly describing

the method calls from one object to another and this is also the actual scenario whenthe system is running.

The Collaboration Diagram:

The second interaction diagram is collaboration diagram. It shows the object

organization as shown below. Here in collaboration diagram the method call sequenceis indicated by some numbering technique as shown below. The number indicates how

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the methods are called one after another. We have taken the same order management

system to describe the collaboration diagram.

The method calls are similar to that of a sequence diagram. But the difference is that

the sequence diagram does not describe the object organization where as the

collaboration diagram shows the object organization.

Now to choose between these two diagrams the main emphasis is given on the type ofrequirement. If the time sequence is important then sequence diagram is used and if

organization is required then collaboration diagram is used.

Where to use Interaction Diagrams?

We have already discussed that interaction diagrams are used to describe dynamicnature of a system. Now we will look into the practical scenarios where these

diagrams are used. To understand the practical application we need to understand the

basic nature of sequence and collaboration diagram.

The main purposes of both the diagrams are similar as they are used to capture the

dynamic behaviour of a system. But the specific purposes are more important to

clarify and understood.

Sequence diagrams are used to capture the order of messages flowing from one object

to another. And the collaboration diagrams are used to describe the structural

organizations of the objects taking part in the interaction. A single diagram is not

sufficient to describe the dynamic aspect of an entire system so a set of diagrams are

used to capture is as a whole.The interaction diagrams are used when we want to understand the message flow and

the structural organization. Now message flow means the sequence of control flow

from one object to another and structural organization means the visual organization

of the elements in a system.

In a brief the following are the usages of interaction diagrams:

To model flow of control by time sequence.

To model flow of control by structural organizations.

For forward engineering.

For reverse engineering.

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STATE CHART DIAGRAM

Overview:

The name of the diagram itself clarifies the purpose of the diagram and other details. Itdescribes different states of a component in a system. The states are specific to a

component/object of a system.

A Statechart diagram describes a state machine. Now to clarify it state machine can be

defined as a machine which defines different states of an object and these states are

controlled by external or internal events.

Activity diagram explained in next chapter, is a special kind of a Statechart diagram.

As Statechart diagram defines states it is used to model lifetime of an object.

Purpose:

Statechart diagram is one of the five UML diagrams used to model dynamic nature of

a system. They define different states of an object during its lifetime. And these states

are changed by events. So Statechart diagrams are useful to model reactive systems.

Reactive systems can be defined as a system that responds to external or internal

events.

Statechart diagram describes the flow of control from one state to another state. States

are defined as a condition in which an object exists and it changes when some event is

triggered. So the most important purpose of Statechart diagram is to model life time of

an object from creation to termination.

Statechart diagrams are also used for forward and reverse engineering of a system. But

the main purpose is to model reactive system.

Following are the main purposes of using Statechart diagrams:

To model dynamic aspect of a system.

To model life time of a reactive system.

To describe different states of an object during its life time.

Define a state machine to model states of an object.


Statechart diagram is used to describe the states of different objects in its life cycle. So

the emphasis is given on the state changes upon some internal or external events.

These states of objects are important to analyze and implement them accurately.

Statechart diagrams are very important for describing the states. States can be

identified as the condition of objects when a particular event occurs.

Before drawing a Statechart diagram we must have clarified the following points:

Identify important objects to be analyzed.

Identify the states.

Identify the events.

The following is an example of a Statechart diagram where the state ofOrderobject isanalyzed.

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The first state is an idle state from where the process starts. The next states are arrived

for events likesend request, confirm request, and dispatch order. These events are

responsible for state changes of order object.

During the life cycle of an object (here order object) it goes through the following

states and there may be some abnormal exists also. This abnormal exit may occur due

to some problem in the system. When the entire life cycle is complete it is consideredas the complete transaction as mentioned below.

The initial and final state of an object is also shown below.

Where to use Interaction Diagrams?

From the above discussion we can define the practical applications of a Statechart

diagram. Statechart diagrams are used to model dynamic aspect of a system like other

four diagrams disused in this tutorial. But it has some distinguishing characteristics for

modeling dynamic nature.

Statechart diagram defines the states of a component and these state changes are

dynamic in nature. So its specific purpose is to define state changes triggered by

events. Events are internal or external factors influencing the system.

Statechart diagrams are used to model states and also events operating on the system.

When implementing a system it is very important to clarify different states of anobject during its life time and statechart diagrams are used for this purpose. When

these states and events are identified they are used to model it and these models are

used during implementation of the system.

If we look into the practical implementation of Statechart diagram then it is mainly

used to analyze the object states influenced by events. This analysis is helpful to

understand the system behaviour during its execution.

So the main usages can be described as:

To model object states of a system.

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To model reactive system. Reactive system consists of reactive objects.

To identify events responsible for state changes.


ACTIVITY DIAGRAMOverview:

Activity diagram is another important diagram in UML to describe dynamic aspects of

the system.

Activity diagram is basically a flow chart to represent the flow form one activity to

another activity. The activity can be described as an operation of the system.

So the control flow is drawn from one operation to another. This flow can be

sequential, branched or concurrent. Activity diagrams deals with all type of flow

control by using different elements like fork, join etc.

Purpose:

The basic purposes of activity diagrams are similar to other four diagrams. It captures

the dynamic behaviour of the system. Other four diagrams are used to show the

message flow from one object to another but activity diagram is used to show message

flow from one activity to another.

Activity is a particular operation of the system. Activity diagrams are not only used

for visualizing dynamic nature of a system but they are also used to construct the

executable system by using forward and reverse engineering techniques. The only

missing thing in activity diagram is the message part.It does not show any message flow from one activity to another. Activity diagram is

some time considered as the flow chart. Although the diagrams looks like a flow chart

but it is not. It shows different flow like parallel, branched, concurrent and single.

So the purposes can be described as:

Draw the activity flow of a system.

Describe the sequence from one activity to another.

Describe the parallel, branched and concurrent flow of the system.


Activity diagrams are mainly used as a flow chart consists of activities performed by

the system. But activity diagram are not exactly a flow chart as they have some

additional capabilities. These additional capabilities include branching, parallel flow,swimlane etc.

Before drawing an activity diagram we must have a clear understanding about the

elements used in activity diagram. The main element of an activity diagram is the

activity itself. An activity is a function performed by the system. After identifying the

activities we need to understand how they are associated with constraints and

conditions.

So before drawing an activity diagram we should identify the following elements:

Activities

Association

Conditions

Constraints

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This diagram is used to model the activities which are nothing but business

requirements. So the diagram has more impact on business understanding rather

implementation details.

Following are the main usages of activity diagram:

Modeling work flow by using activities.

Modeling business requirements. High level understanding of the system's functionalities.

Investigate business requirements at a later stage.

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COMPONENT DIAGRAMOverview:

Component diagrams are different in terms of nature and behaviour. Component

diagrams are used to model physical aspects of a system.Now the question is what are these physical aspects? Physical aspects are the elements

like executables, libraries, files, documents etc which resides in a node.

So component diagrams are used to visualize the organization and relationships

among components in a system. These diagrams are also used to make executable

systems.

Purpose:

Component diagram is a special kind of diagram in UML. The purpose is also

different from all other diagrams discussed so far. It does not describe the

functionality of the system but it describes the components used to make those

functionalities.

So from that point component diagrams are used to visualize the physical components

in a system. These components are libraries, packages, files etc.

Component diagrams can also be described as a static implementation view of a

system. Static implementation represents the organization of the components at a

particular moment.

A single component diagram cannot represent the entire system but a collection of

diagrams are used to represent the whole.

So the purpose of the component diagram can be summarized as:

Visualize the components of a system.

Construct executables by using forward and reverse engineering.

Describe the organization and relationships of the components.


Component diagrams are used to describe the physical artifacts of a system. This

artifact includes files, executables, libraries etc.

So the purpose of this diagram is different, Component diagrams are used during theimplementation phase of an application. But it is prepared well in advance to visualize

the implementation details.

Initially the system is designed using different UML diagrams and then when the

artifacts are ready component diagrams are used to get an idea of the implementation.

This diagram is very important because without it the application cannot be

implemented efficiently. A well prepared component diagram is also important for

other aspects like application performance, maintenance etc.

So before drawing a component diagram the following artifacts are to be identified

clearly:

Files used in the system.

Libraries and other artifacts relevant to the application. Relationships among the artifacts.

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Now after identifying the artifacts the following points needs to be followed:

Use a meaningful name to identify the component for which the diagram is to

be drawn.

Prepare a mental layout before producing using tools.

Use notes for clarifying important points.

The following is a component diagram for order management system. Here theartifacts are files. So the diagram shows the files in the application and their

relationships. In actual the component diagram also contains dlls, libraries, folders etc.

In the following diagram four files are identified and their relationships are produced.

Component diagram cannot be matched directly with other UML diagrams discussed

so far. Because it is drawn for completely different purpose.

So the following component diagram has been drawn considering all the points

mentioned above:

Where to use Component Diagrams?

We have already described that component diagrams are used to visualize the static

implementation view of a system. Component diagrams are special type of UML

diagrams used for different purposes.

These diagrams show the physical components of a system. To clarify it, we can saythat component diagrams describe the organization of the components in a system.

Organization can be further described as the location of the components in a system.

These components are organized in a special way to meet the system requirements.

As we have already discussed those components are libraries, files, executables etc.

Now before implementing the application these components are to be organized. This

component organization is also designed separately as a part of project execution.

Component diagrams are very important from implementation perspective. So the

implementation team of an application should have a proper knowledge of the

component details.

Now the usage of component diagrams can be described as:

Model the components of a system. Model database schema.

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Model executables of an application.

Model system's source code.

DEPLOYMENT DIAGRAM

Overview:

Deployment diagrams are used to visualize the topology of the physical components

of a system where the software components are deployed.

So deployment diagrams are used to describe the static deployment view of a system.

Deployment diagrams consist of nodes and their relationships.

Purpose:

The nameDeploymentitself describes the purpose of the diagram. Deployment

diagrams are used for describing the hardware components where software

components are deployed. Component diagrams and deployment diagrams are closely

related.

Component diagrams are used to describe the components and deployment diagrams

shows how they are deployed in hardware.

UML is mainly designed to focus on software artifacts of a system. But these two

diagrams are special diagrams used to focus on software components and hardware

components.So most of the UML diagrams are used to handle logical components but deployment

diagrams are made to focus on hardware topology of a system. Deployment diagrams

are used by the system engineers.

The purpose of deployment diagrams can be described as:

Visualize hardware topology of a system.

Describe the hardware components used to deploy software components.

Describe runtime processing nodes.


Deployment diagram represents the deployment view of a system. It is related to the

component diagram. Because the components are deployed using the deployment

diagrams. A deployment diagram consists of nodes. Nodes are nothing but physical

hardwares used to deploy the application.

Deployment diagrams are useful for system engineers. An efficient deployment

diagram is very important because it controls the following parameters

Performance

Scalability

Maintainability

Portability

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So before drawing a deployment diagram the following artifacts should be identified:

Nodes

Relationships among nodes

The following deployment diagram is a sample to give an idea of the deployment view

of order management system. Here we have shown nodes as:

Monitor Modem

Caching server

Server

The application is assumed to be a web based application which is deployed in a

clustered environment using server 1, server 2 and server 3. The user is connecting to

the application using internet. The control is flowing from the caching server to the

clustered environment.

So the following deployment diagram has been drawn considering all the points

mentioned above:

Where to use Deployment Diagrams?

Deployment diagrams are mainly used by system engineers. These diagrams are used

to describe the physical components (hardwares), their distribution and association.To clarify it in details we can visualize deployment diagrams as the hardware

components/nodes on which software components reside.

Software applications are developed to model complex business processes. Only

efficient software applications are not sufficient to meet business requirements.

Business requirements can be described as to support increasing number of users,

quick response time etc.

To meet these types of requirements hardware components should be designed

efficiently and in a cost effective way.

Now a day's software applications are very complex in nature. Software applications

can be stand alone, web based, distributed, mainframe based and many more. So it is

very important to design the hardware components efficiently.So the usage of deployment diagrams can be described as follows:

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To model the hardware topology of a system.

To model embedded system.

To model hardware details for a client/server system.

To model hardware details of a distributed application.


UML NOTATIONS

UML notations are the most important elements in modeling. Efficient and appropriate

use of notations is very important for making a complete and meaningful model. The

model is useless unless its purpose is depicted properly.

So learning notations should be emphasized from the very beginning. Different

notations are available for things and relationships. And the UML diagrams are madeusing the notations of things and relationships. Extensibility is another important

feature which makes UML more powerful and flexible.

The chapter describes the UML Basic Notations in more details. This is just an

extension to the UML buildling block section I have discussed in previous chapter.

Structural Things:

Graphical notations used in structural things are the most widely used in UML. These

are considered as the nouns of UML models. Following are the list of structural things.

Classes

Interface

Collaboration

Use case Active classes

Components

Nodes

Class Notation:

UML class is represented by the diagram shown below. The diagram is dividedinto four parts.

The top section is used to name the class.

The second one is used to show the attributes of the class.

The third section is used to describe the operations performed by the class.

The fourth section is optional to show any additional components.

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Classes are used to represent objects. Objects can be anything having properties and

responsibility.

Object Notation:

The objectis represented in the same way as the class. The only difference is the

name which is underlined as shown below..

As object is the actual implementation of a class which is known as the instance of a

class. So it has the same usage as the class.

Interface Notation:

Interface is represented by a circle as shown below. It has a name which is generally

written below the circle.

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Interface is used to describe functionality without implementation. Interface is the just

like a template where you define different functions not the implementation. When a

class implements the interface it also implements the functionality as per the

requirement.

Collaboration Notation:

Collaboration is represented by a dotted eclipse as shown below. It has a name written

inside the eclipse.

Collaboration represents responsibilities. Generally responsibilities are in a group.

Use case Notation:

Use case is represented as an eclipse with a name inside it. It may contain additional

responsibilities.

Use case is used to capture high level functionalities of a system.

Actor Notation:

An actor can be defined as some internal or external entity that interacts with thesystem.

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Actor is used in a use case diagram to describe the internal or external entities.

Initial State Notation:

Initial state is defined show the start of a process. This notation is used in almost all

diagrams.

The usage of Initial State Notation is to show the starting point of a process.

Final State Notation:

Final state is used to show the end of a process. This notation is also used in almost all

diagrams to describe the end.

The usage of Final State Notation is to show the termination point of a process.

Active class Notation:

Active class looks similar to a class with a solid border. Active class is generally used

to describe concurrent behaviour of a system.

Active class is used to represent concurrency in a system.

Component Notation:

A component in UML is shown as below with a name inside. Additional elements can

be added wherever required.

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Component is used to represent any part of a system for which UML diagrams are

made.

Node Notation:

A node in UML is represented by a square box as shown below with a name. A node

represents a physical component of the system.

Node is used to represent physical part of a system like server, network etc.

Behavioural Things:Dynamic parts are one of the most important elements in UML. UML has a set of

powerful features to represent the dynamic part of software and non software systems.

These features include interactions andstate machines.

Interactions can be of two types:

Sequential (Represented by sequence diagram)

Collaborative (Represented by collaboration diagram)

Interaction Notation:

Interaction is basically message exchange between two UML components. The

following diagram represents different notations used in an interaction.

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Interaction is used to represent communication among the components of a system.

State machine Notation:

State machine describes the different states of a component in its life cycle. The

notations are described in the following diagram.

State machine is used to describe different states of a system component. The state can

be active, idle or any other depending upon the situation.

Grouping Things:

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Organizing the UML models are one of the most important aspects of the design. In

UML there is only one element available for grouping and that is package.

Package Notation:

Package notation is shown below and this is used to wrap the components of a system.

Annotational Things:

In any diagram explanation of different elements and their functionalities are very

important. So UML has notes notation to support this requirement.Note Notation:

This notation is shown below and they are used to provide necessary information of a

system.

Relationships

A model is not complete unless the relationships between elements are described

properly. TheRelationship gives a proper meaning to an UML model. Following arethe different types of relationships available in UML.

Dependency

Association

Generalization

Extensibility

Dependency Notation:

Dependency is an important aspect in UML elements. It describes the dependent

elements and the direction of dependency.

Dependency is represented by a dotted arrow as shown below. The arrow headrepresents the independent element and the other end the dependent element.

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Dependency is used to represent dependency between two elements of a system.

Association Notation:

Association describes how the elements in an UML diagram are associated. In simple

word it describes how many elements are taking part in an interaction.

Association is represented by a dotted line with (without) arrows on both sides. The

two ends represent two associated elements as shown below. The multiplicity is also

mentioned at the ends (1, * etc) to show how many objects are associated.

Association is used to represent the relationship between two elements of a system.

Generalization Notation:

Generalization describes the inheritance relationship of the object oriented world. It is

parent and child relationship.

Generalization is represented by an arrow with hollow arrow head as shown below.

One end represents the parent element and the other end child element.

Generalization is used to describe parent-child relationship of two elements of a

system.

Extensibility Notation:

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All the languages (programming or modeling) have some mechanism to extend its

capabilities like syntax, semantics etc. UML is also having the following mechanisms

to provide extensibility features.

Stereotypes (Represents new elements)

Tagged values (Represents new attributes)

Constraints (Represents the boundaries)

Extensibility notations are used to enhance the power of the language. It is basically

additional elements used to represent some extra behaviour of the system. These extra

behaviours are not covered by the standard available notations.

Abstraction Relationship

An abstraction relationship is a dependency between model elements that represents

the same concept at different levels of abstraction or from different viewpoints. You

can add abstraction relationships to a model in several diagrams, including use-case,

class, and component diagrams.

Activity edgesIn activity diagrams, an activity edge is a relationship between two activity nodes that

you can use to represent the control flow or object flow in an activity diagram.

Aggregation relationships

An aggregation relationship depicts a classifier as a part of, or as subordinate to,another classifier.

Association relationships

In UML models, an association is a relationship between two classifiers, such as

classes or use cases, that describes the reasons for the relationship and the rules that

govern the relationship.

Binding relationships

In UML models, a binding relationship is a relationship that assigns values to template

parameters and generates a new model element from the template.

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Communication paths

In UML modeling, a communication path is a type of association between nodes in a

deployment diagram that shows how the nodes exchange messages and signals.

Composition relationships

A composition relationship, which was named composition association relationship inUML 1.4, represents wholepart relationships and is a form of aggregation. A

composition relationship specifies that the lifetime of the part classifier is dependent

on the lifetime of the whole classifier.

Dependency relationships

In UML modeling, a dependency relationship is a relationship in which changes to one

model element (the supplier) impact another model element (the client). You can use

dependency relationships in class diagrams, component diagrams, deployment

diagrams, and use case diagrams.

Deployment relationshipsIn UML modeling, deployment relationships specify that a particular node type

supports the deployment of an artifact type.

Directed association relationships

In UML models, directed association relationships are associations that are navigable

in only one direction.

Generalization relationships

In UML modeling, a generalization relationship is a relationship in which one model

element (the child) is based on another model element (the parent). Generalization

relationships are used in class, component, deployment, and use case diagrams.

Implementation relationships

In UML modeling, an implementation relationship is a specialized type of realization

relationship between a classifier and a provided interface. The implementation

relationship specifies that the realizing classifier must conform to the contract that the

provided interface specifies.

Include relationships

In UML modeling, an include relationship is a relationship in which one use case (the

base use case) includes the functionality of another use case (the inclusion use case).

The include relationship supports the reuse of functionality in a use case model.

Manifestation relationships

In UML modeling, a manifestation relationship shows which model elements, such as

components or classes, are manifested in an artifact. The artifact manifests, or

includes, a specific implementation for, the features of one or several physical

software components.

Realization relationships

In UML modeling, a realization relationship is a relationship between two model

elements, in which one model element (the client) realizes the behavior that the other

model element (the supplier) specifies. Several clients can realize the behavior of a

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single supplier. You can use realization relationships in class diagrams and component

diagrams.

Usage relationships

In UML modeling, a usage relationship is a type of dependency relationship in which

one model element (the client) requires another model element (the supplier) for fullimplementation or operation.

Common Mechanisms In UML

Specifications

textual statement of syntax & semantics

diagrams give view of specification

Adornments

elements in UML - unique graphical notation

adornments - added information about class

Common Divisions

general property vs. specific instance

class vs. objectuse case vs. use case instance

UML syntax: underline name of instance

separation of interface & implementation

interface - contract

implementation - concrete realization of contract

Extensibility Mechanisms

stereotype

allows creation of new kinds of building blocks from existing ones

tagged value

allows creation of new information in specification

constraint

allows addition of new rules & modification of existing rules

Rules Of UML specify what model should look like

semantic rules for

names

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scope

visibility

integrity

execution

Common properties of models

elided - hide some elements for simplicity

incomplete

inconsistent

rules of UML make it easier to address these problems

TERMS AND CONCEPTS

UML 2.2 has 14 types ofdiagrams divided into two categories.[10] Seven diagram

types represent structural information, and the other seven represent general types of

behavior, including four that represent different aspects of interactions. These

diagrams can be categorized hierarchically as shown in the following class diagram:

UML does not restrict UML element types to a certain diagram type. In general, every

UML element may appear on almost all types of diagrams; this flexibility has been

partially restricted in UML 2.0. UMLprofiles may define additional diagram types or

extend existing diagrams with additional notations.

In keeping with the tradition of engineering drawings, a comment or note explaining

usage, constraint, or intent is allowed in a UML diagram.

Structure diagrams

Structure diagrams emphasize what things must be in the system being

modeled:

Class diagram: the class diagrams describes the structure of a system by

showing the system's classes, their attributes, and the relationships among the

classes.

Component diagram: depicts how a software system is split up into

components and shows the dependencies among these components.

Composite structure diagram: describes the internal structure of a class and the

collaborations that this structure makes possible.

Deployment diagram: serves to model the hardware used in system

implementations, and the execution environments and artifacts deployed on thehardware.

Object diagram: shows a complete or partial view of the structure of a modeled

system at a specific time.

Package diagram: depicts how a system is split up into logical groupings by

showing the dependencies among these groupings.

Profile diagram: operates at the metamodel level to show stereotypes as classes

with the stereotype, and profiles as packages with the

stereotype. The extension relation (solid line with closed, filled

arrowhead) indicate what metamodel element a given stereotype is extending.

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Since structure diagrams represent the structure they are used extensively in

documenting the architecture of software systems.

Behavior diagrams

Behavior diagrams emphasize what must happen in the system being modeled:

Activity diagram: represents the business and operational step-by-step

workflows of components in a system. An activity diagram shows the

overall flow of control.

State machine diagram: standardized notation to describe many systems,

from computer programs to business processes.

Use case diagram: shows the functionality provided by a system in terms of

actors, their goals represented as use cases, and any dependencies among

those use cases.

Since behavior diagrams illustrate the behaviour of a system, they are used extensively

to describe the functionality of software systems.

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CLASS DIAGRAM

The class diagram describes the attributes and operations of a class and also the

constraints imposed on the system. The class diagrams are widely used in the

modelling of object oriented systems because they are the only UML diagrams which

can be mapped directly with object oriented languages.

The class diagram shows a collection of classes, interfaces, associations,

collaborations and constraints. It is also known as astructural diagram.

Contents:Class diagrams commonly contain the following things

Classes Interfaces

Collaborations

Dependency,generation and association relationships

Fig: Class Diagram

Class Diagram for Airline Reservation System

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Reservation incharge

Incharge name

incharge id

inchrg location

accept()

reject()

update database()

manage payment()

Traveller

Name

Passport no.

Telephone no.

Address

Viewinfo()Booking()

Payment()

cancel_reservation()

Date_change()

Airline Database

Airline name

Date of update

update time table()

update cost info()

update changes to database()

USE CASE DIAGRAM

Use case diagrams are used to gather the requirements of a system including internal

and external influences. These requirements are mostly design requirements. So when

a system is analyzed to gather its functionalities use cases are prepared and actors are

identified.Now when the initial task is complete use case diagrams are modelled to present the

outside view.

So in brief, the purposes of use case diagrams can be as follows:

Used to gather requirements of a system.

Used to get an outside view of a system.

Identify external and internal factors influencing the system.

Show the interacting among the requirements are actors.

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Fig: Use Case Diagram

INTERACTION DIAGRAM

That is why sequence and collaboration diagrams are used to capture dynamic nature

but from a different angle.

So the purposes of interaction diagram can be describes as:

To capture dynamic behaviour of a system.

To describe the message flow in the system. To describe structural organization of the objects.

To describe interaction among objects.

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accept request

deny requestt

accept payment

Reservation

incharge

show avbl flights

Airline Reservation

Database

pay money

select destination

purchase ticket

Search for flights

make reservation

cancel reservation

traveller


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Fig:Sequence Diagram

Fig: Collaboration Diagram

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SEQUENCE DIAGRAM FOR CHANGING

RESERVATION

TravellerTraveller : Booking

System

: Booking

System

Reservation

incharge

Reservation

incharge

Airline

reservation DB

Airline

reservation DB

1: change reservation2: Get customer details

3: get itineary

4: show itineray

5: select segment

6: present detailed info

7: select avbl flights

8: show avbl flights

9: payment

10: update database

11: generate report

Fig: Sequence Diagram

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COLLABORATION DIAGRAM FOR CHANGINGRESERVATION

R e s e r v a t i o n

i n c h a r g e

Trave l le r

A i r l i n e

r e s e r va t i o n D B

: B o o k i ng

S y s t e m

1 0 : u p d a t e d a t a b a s e

1 : c h a n g e r e s e r va t i o n5 : s e le c t s e g m e n t

4 : s h o w i t i ne r a y6 : p r e s e n t d e t a i le d i n f o

9 : pa y m e n t

1 1 : g e n e r a t e r e p o rt

8 : s h o w a vb l f l igh ts

2 : G e t c u s t o m e r d e t a il s

3 : g e t i t in e a r y

7 : s e l e c t a v b l f l i g h t s

Fig: Collaboration Diagram

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ACTIVITY DIAGRAM

Activity diagram is another important diagram in UML to describe dynamic aspects of

the system.

Activity diagram is basically a flow chart to represent the flow form one activity to

another activity. The activity can be described as an operation of the system.

So the control flow is drawn from one operation to another. This flow can be

sequential, branched or concurrent. Activity diagrams deals with all type of flow

control by using different elements like fork, join et

Branching

A branch specifies alternate paths takes based on some Boolean expression

Branch is represented by diamond

Branch may have one incoming transition and two or more outgoing one on each

outgoing transition,you place a Boolean expression shouldnt overlap but they should

cover all possibilities.

Forking and Joining

ForkA fork represents the splitting of a single flow of control into two or more concurrent

Flow of control.

A fork may have one incoming transition and two or more outgoing transitions, each

of which represents an independent flow of control.

Below fork the activities associated with each of these path continues in parallel.

JoinA join represents the synchronization of two or more concurrent flows of control.

A join may have two or more incoming transition and one outgoing transition.

Above the join the activities associated with each of these paths continues in parallel.

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Swimlane:Swimlanes are useful when we model workflows of business processes to partition the

activity states on an activity diagram into groups.

Each group representing the business organization responsible for those

activities,these groups are called swimlanes.

ACTIVITY DIAGRAM FOR MAKING RESERVATION

Select Flight

Available

Submit Request

Not Available

Accepted Rejected

Payment

View Report

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ACTIVITY DIAGRAM FOR CHANGING RESERVATION

Cancel

Reservation

New reservation Get Refunded

Submit Request

Select Flight

Accept Reject

View Report

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SWIMLANE DIAGRAM FOR AIRLINE RESERVATION

SYSTEM

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Submit

Request

View report

Payment

Print Reciept

View

AcceptReject

Generate

Report

Generate

Receipt

Review data

Store Data

Store data

Retrieve data

Airline re serv ation databaseReserv ation InchargeTraveller

STATE CHART DIAGRAM

A state chart diagrams a state machine, emphasizing the flow of control from state to

state.

Contents

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State chart diagrams commonly contain

Simply state and composite states

Transitions, including events and actions

Common use

They are use to model the dynamic aspects of a system.

Event ordered behavior of any kind of objects, to model reactive objects.

ACTIVE

SubmittingRequest

Processing

Request

Generating

Report

SubmittingRequest

Processing

Request

Generating

Report

START

EXIT

FIG. for the State diagram of Airline Reservation System

COMPONENT DIAGRAM

Component diagrams are different in terms of nature and behaviour. Component

diagrams are used to model physical aspects of a system.

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Now the question is what are these physical aspects? Physical aspects are the elements

like executables, libraries, files, documents etc which resides in a node.

So component diagrams are used to visualize the organization and relationships

among components in a system. These diagrams are also used to make executable

systems.

Fig: Component Diagram

DEPLOYMENT DIAGRAM

Deployment diagrams are used to visualize the topology of the physical components

of a system where the software components are deployed.

So deployment diagrams are used to describe the static deployment view of a system.Deployment diagrams consist of nodes and their relationships.

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Airline

Resevation.exe

.dll doc

ARS.java

.flv

Airline Database


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Purpose:

The nameDeploymentitself describes the purpose of the diagram. Deployment

diagrams are used for describing the hardware components where software

components are deployed. Component diagrams and deployment diagrams are closely

related.

Component diagrams are used to describe the components and deployment diagramsshows how they are deployed in hardware.

Fig: Deployment Diagram

DEPLOYMENT DIAGRAM FOR AIRLINE RESERVATION

SYSTEM

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Fig: Deployment Diagram

Airline

Reservation

Database

ReservationIncharge

Traveller 1 Traveller 2Traveller n

31081831 Airline Reservation System

Documents

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