Educational Forum & Online Mesging System Bca

7/28/2019 Educational Forum & Online Mesging System Bca

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PROJECT REPORT

ON

EDUCATIONAL FORUM & ONLINE MESGING

SYSTEM

SUBMITTED UNDER PARTIAL FULFILLMENT OF THE REQUIREMENT

FOR THE

AWARD OF DEGREE OF THREE YEAR FULL TIME

BACHELOR OF COMPUTER APPLICATION(2009-2012)

OF

MAHATMA GANDHI KASHI VIDYAPITH

VARANASIGUIDED BY:- SUBMITTEDBY:-

Mr. Ram GopalGupta Niraj Srivastava

Senior Lecturer Roll No. - 11410050069

SMS VARANASI Rahul Sharma

Roll No. - 11410050083

Vikas Singh

Roll No. - 11410050119

BCA 6th SEMESTER

SCHOOL OF MANAGEMENT SCIENCES

VARANASI


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CERTIFICATE


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ACKNOWLEDGEMENT

ACKNOWLEDGEMENT-

We would like to add few heartfelt words for the people who were parts of this

project and its report in numerous ways. First of all, We would like to expressour profound sense of gratitude and veneration to Prof.P.N. Jha , Director of

school of management sciences . Also it gives immense pleasure to express my

gratitude to my projrct leader and project guide Mr. Ram Gopal Gupta,

Lecturer, under whose able, experienced and dynamic guidance the present


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work has carried out. His sincere encouragement and enumerable valuable

discussion were a constant source of inspiration to us.

We are highly thankful to our coordinatorMr. Rajeev Katare for his valuable

suggestion. Last but not leastwe would like to thanks all of our friend and

parents for their moral support under whose valuable co-operation and

encouragement our knowledge in computer application got an edge.

SIGNATURE

Place: Name: ...

Date: ... Roll No. ..


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PREFACE

PREFACE

Periods where major emphasis is to create an ideal system , which has

maximum throughput with highest capability. Now a day, the scientific &

technology research work is going on massively to understand natural events.

Modern age is an age of computer. Now the whole world activities are being

dependent on the computers.

The world computer stands for easy accessible time saving provide accurate

data and so on. So a computer is normally being an accessing device to process

query can figure out query result with in a very short span of time. This


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electronic device is highly efficient fast accurate machine capable of processing

query performing routine as prescribed by the user.

My intention worst to develop a file transfer protocol which is use to share the

file from a remote control to host computer over internet because now a daymobility is very need full in network oriented system.


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PROJECT TITLE

EDCATIONAL FORUM

AND

ONLINE MESSAGING SYSTEM


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CONTENTS


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TABLE OF CONTENTS

ACKNOWLEDGEMENT

TABLES OF CONTENTS

INTRODUCATION TO PROJECT

OBJECTIVES

OVERVIEW OF ELEMENT USED IN PROJECT

Internet

Java

JAVA PLATEFORM

CONCEPT OF OOP S & PACKAGES

JSP(JAVA SERVER PAGE)

Oracle(Data Base)

ORACLE

DBMS

INTIGRITY RULE

FEASIBILITY ANALYSIS

TECHNICAL FEASIBILITY

OPERATIONL FEASIBILITY

ECONOMICAL FEASIBILITY

HARDWARE REQUIREMENT

SOFTWARE REQUIREMENT

DATA FLOW DIAGRAM

DATA FLOW DAIGRAM

DFD SYMBOL

0- LEVEL

1 - LEVEL DFD

1-LEVEL DFD OF ONLINE MESSAGING

ENTITY RELATIONSHIP

DAIGRAM

E-R MODEL

E-R DAIGRAM


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FUTURE ENHANCEMENT

CONCLUSION

BIBLIOGRAPHY


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INTRODUCTION

INTRODUCTION OF THE PROJECT

Before Starting the project we should fully know about the meaning of project.

There are seven letters in the word PROJECT each character has its own

technical meaning.


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Planning

This deal with the idea at thinking and which are required for the

project.

Resource

The money problem will be solved and resources from which

collected.

Operating

The procedure from which the getting job is prepared in a systematic

way is known as operation.

Joint effort

This is directly proper to a operation output is made of several person

working sincerely is known as JOINT EFFORT.

Engineering

A well-educated engineer can do this work in a better way to find out

better result. Hence the project is as engineering function.

Co-operation

To make the project successfully, it is necessary for its success and

completion of project.

Technique

It must as it gives a better shape. It is not possible to complete the

project without technique.

The simplistic definition of a forum is a place where people have the ability to

start communication (in the form of threads) and reply to other people's threads.A member of the community in the forum posts a message, which is visible to

everyone in that community. Once read, there is the option to post a reply,

which can also be visible to the community. Thus, a discussion can build up

without all users having to be online at the same time.


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Online messaging system refers to The Online Messaging and Conferencing

system is designed to provide fast, and reliable communication services in using

the Internet as a medium. This project will enable internet users to send text

messages.


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OBJECTIVE

OBJECTIVES

Main Objective for Forum in Fairness in Education are :

1. To creat conditions Conducive to bring about 100% literacy amongst theindian populace in general and in the age group of 5 years to 14 years in

particular.

2. To make efforts to ensure dignity for proper and adequate pay andallowances to teaching staff so as to attract talented persons through

unbiased mechanimsm of selection.

3. To make efforts for periodical review of Urban Development Plans with aview to avoid concentration of urban / educational institutions in some

areas and creating deficiency in other areas. To endeavour to compensate


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for the loss of land for educational sector due to faulty urban land policyor due to faulty implementation or due to gross impropriety.

.

4. To educate teacher in particular and parent in general on harmful effectsof over-burdening children by imposing heavy syllabi and tasks beyond

their capacity

.

5. To sugest and / or recommend the minimum requirements forrecognition/affiliation of educational institutions to the appropriate

bodies.

.

6. To make efforts to uphold and to implement the principle of merit foradmission to educational institutions as against reservation of seats for

donors, management, government, with the exception of reservation forbackward classes and special concession for those who have shown

recognised merit in sports, gymnastics, fine arts, oratory and such otherskills.

.

7. To undertake survey, investigation, research and action for ultimate totalabolition of the reservation policy in a time bound programme with

cooperation of the beneficiaries and to review the educational, financial

and cultural advancement of the backward classes from 1950 onwards

when the nation become a Republic and chart out the thrust areas ofconcerted action.

.

8. To make efforts for reviewing the criteria for granting minority status toeducational institutions under article 29 and 30 of the Constitution of

India so as to bring it in line with the true meaning and interpretation of

the constitutional provision and judicial pronouncements to prevent themisuse thereof.

.

9. To make efforts at the level of Govt. if India and State Governments forbanning admissions to educational institutions on payment of donations,

Capitation fee or other contribution and for enactment of suitable

legislation providing for cognizable offence under Criminal ProcedureCode.


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.

10.To arouse public awareness in the matters of financial irregularities,corrupt practices malpractices and misappropriation of of funds in the

field of education with a view to ensuring fairness in education.

.

11.To make efforts to remove the disparties in facilities and amenitiesbetween the rural municipal govt. institutions on one hand and the elite

institutions with star facilities on the other hand.

.

12.To make efforts for making educational institutions run by privatemanagements/voluntary organisations with and / or wihout government

grants equally accountable to the public authorities.

.

13.To make efforts for establishment of adequate number of Tribunals fordifferent levels and disciplines so as to ensure speedy redressals of

disputes between managements of educational institutions and theiremployees

.

14.To make efforts to prevent brain drain from country by imposingimigration levy or compulsory service etc. on the technical, medical and

other skilled professionals.

.

15.To make the parents, teachers, students aware of the current laws/rulescourt orders pertaining to the education.

.

16.To bring about Accountability, Reasonability & Transparency in the fieldof Education


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OVER VIEW OFELEMENT USED IN

PROJECT


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1.INTERNET

A global network connecting millions ofcomputers. More than 100 countries

are linked into exchanges ofdata, news and opinions. Unlikeonline services,

which are centrally controlled, the Internet is decentralized by design. Each

Internet computer, called ahost, is independent. Its operators can choose whichInternet services to use and whichlocalservices to make available to the global

Internet community. Remarkably, this anarchy by design works exceedingly

well. There are a variety of ways toaccessthe Internet. Most online services,

such asAmerica Online, offer access to some Internet services. It is also

possible to gain access through a commercialInternet Service Provider (ISP).The Internetis not synonymous withWorld Wide Web.

The internet is the most powerful and economical communication

medium in the world today. Communication on the internet is done

primarily through the use of e-mail and instant messenger. The Internet isa global system of interconnected computer networks that interchange

data by packet switching using the standardized Internet Protocol Suite

(TCP/IP). It is a "network of networks" that consists of millions of privateand public, academic, business, and government networks of local to

global scope that are linked by copper wires, fiber-optic cables, wirelessconnections, and other technologies.
http://www.webopedia.com/TERM/C/computer.htmhttp://www.webopedia.com/TERM/C/computer.htmhttp://www.webopedia.com/TERM/C/computer.htmhttp://www.webopedia.com/TERM/D/data.htmhttp://www.webopedia.com/TERM/D/data.htmhttp://www.webopedia.com/TERM/D/data.htmhttp://www.webopedia.com/TERM/O/online_service.htmhttp://www.webopedia.com/TERM/O/online_service.htmhttp://www.webopedia.com/TERM/O/online_service.htmhttp://www.webopedia.com/TERM/H/host.htmhttp://www.webopedia.com/TERM/H/host.htmhttp://www.webopedia.com/TERM/H/host.htmhttp://www.webopedia.com/TERM/L/local.htmhttp://www.webopedia.com/TERM/L/local.htmhttp://www.webopedia.com/TERM/L/local.htmhttp://www.webopedia.com/TERM/A/access.htmhttp://www.webopedia.com/TERM/A/access.htmhttp://www.webopedia.com/TERM/A/access.htmhttp://www.webopedia.com/TERM/A/America_Online.htmhttp://www.webopedia.com/TERM/A/America_Online.htmhttp://www.webopedia.com/TERM/A/America_Online.htmhttp://www.webopedia.com/TERM/I/ISP.htmhttp://www.webopedia.com/TERM/I/ISP.htmhttp://www.webopedia.com/TERM/I/ISP.htmhttp://www.webopedia.com/TERM/W/World_Wide_Web.htmlhttp://www.webopedia.com/TERM/W/World_Wide_Web.htmlhttp://www.webopedia.com/TERM/W/World_Wide_Web.htmlhttp://www.webopedia.com/TERM/W/World_Wide_Web.htmlhttp://www.webopedia.com/TERM/I/ISP.htmhttp://www.webopedia.com/TERM/A/America_Online.htmhttp://www.webopedia.com/TERM/A/access.htmhttp://www.webopedia.com/TERM/L/local.htmhttp://www.webopedia.com/TERM/H/host.htmhttp://www.webopedia.com/TERM/O/online_service.htmhttp://www.webopedia.com/TERM/D/data.htmhttp://www.webopedia.com/TERM/C/computer.htm


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2.JAVAJAVA

Java is a programming language originally developed by SunMicrosystems and released in 1995 as a core component of Sun

Microsystems' Java platform. The language derives much of its syntax

from C and C++ but has a simpler object model and fewer low-level

facilities. Java applications are typically compiled to byte code that can runon any Java virtual machine (JVM) regardless of computer architecture.

The original and reference implementation Java compilers, virtualmachines, and class libraries were developed by Sun from 1995.

The Java programming language is a high-level language that can becharacterized by all of the following buzzwords:

Simple

Object oriented Distributed

Multithreaded

Dynamic

Architecture neutral

Portable

In the Java programming language, all source code is first written in plaintext files ending with the .java extension. Those source files are then

compiled into .class files by the javac compiler. A .class file does not

contain code that is native to your processor; it instead contains bytecodes

the machine language of the Java Virtual Machine (Java VM). The java

launcher tool then runs your application with an instance of the Java

Virtual Machine.


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The Java Platform:-

A platform is the hardware or software environment in which a program

runs. We've already mentioned some of the most popular platforms like

Microsoft Windows, Linux, Solaris OS, and Mac OS. Most platforms can

be described as a combination of the operating system and underlying

hardware. The Java platform differs from most other platforms in that it's a

software-only platform that runs on top of other hardware-based platforms.

The Java platform has two components :-

The Java Virtual Machine The Java Application Programming Interface (API)

You've already been introduced to the Java Virtual Machine; it's the basefor the Java platform and is ported onto various hardware-based platforms.

The API is a large collection of ready-made software components that

provide many useful capabilities. It is grouped into libraries of related

classes and interfaces; these libraries are known aspackages. The next

section, What Can Java Technology Do? highlights some of the

functionality provided by the API.

The API and Java Virtual Machine insulate the program from the

underlying hardware .

As a platform-independent environment, the Java platform can be a bit

slower than native code. However, advances in compiler and virtual

machine technologies are bringing performance close to that of native code

without threatening portability.


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Some useful keywords of java.


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CONCEPT OF

OOPS &

PACKAGES

What Is an Object?An object is a software bundle of related state and behavior. Software

objects are often used to model the real-world objects that you find in

everyday life. This lesson explains how state and behavior are represented

within an object, introduces the concept of data encapsulation, and explains

the benefits of designing your software in this manner.

What Is a Class?

A class is a blueprint or prototype from which objects are created. This

section defines a class that models the state and behavior of a

real- world object. It intentionally focuses on the basics, showing how even

a simple class can cleanly model state and behavior.

What Is Inheritance?

An interface is a contract betweena class and the outside world. When a

class implements an interface, it promises to provide the behaviorpublished by that interface. This section defines a simple interface and

explains the necessary changes for any class that implements it.

What Is an Interface?An interface is a contract between a class and the outside world. When a

class implements an interface, it promises to provide the

behaviourpublished by that interface. This section defines a simple


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interface and explains the necessary changes for any class that implements

it.

What Is a Package?

A package is a namespace for organizing classes and interfaces in a logical

manner. Placing your code into packages makes large software projects

easier to manage. This section explains why this is useful, and introduces

you to the Application Programming Interface (API) provided by the Java

platform.

Java has significant advantages over other languages and environments that

make it suitable for just about any programming task.

The advantages of Java are as follows:

Java was designed to be easy to use and is therefore easy towrite, compile, debug, and learn than other programming

languages.

This allows us to create modular programs and reusable code.

One of the most significant advantages of Java is its ability to move easily

from one computer system to another. The ability to run the same program onmany different systems is crucial to World Wide Web software, and Java

succeeds at this by being platform-independent at both the source and binary

level.

Data Abstraction and Encapsulation:-

The wrapping of data and function into single unit (class) is known as

Encapsulation. The data is not accessible to outside world, only thosefunctions can access which are wrapped in with that data. The Insulation of

data from direct access is called Data Hiding.

Abstraction refers to the act of representing the essential feature without

representing the details or explanations. Classes use the concept of


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abstraction and are defined as a list of abstract attributes such as size,

weight, and cost.

The wrapping of data and function into single unit (class) is known as

Encapsulation. The data is not accessible to outside world, only those functionscan access which are wrapped in with that data. The Insulation of data from direct

access is called Data Hiding.

Java has significant advantages over other languages and environments that make

it suitable for just about any programming task.

Inheritance:-Inheritance is the process by which objects of one class acquire the properties of

the objects of another class. It means we can add additional features to the class

without modifying it. This is possible by deriving a new class from the existing

one. The new class will have combined feature of both the classes.

Polymorphism:-

Polymorphism means the ability to take different forms at different instances. An

operator may exhibit different behaviors at different instances this feature is

called as Operator Overloading Polymorphism also provide the concept ofFunctional overloading which means single function can perform different task

with same name.

.


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JSP (JAVA SERVER PAGES )

Architecturally, JSP may be viewed as a high-level abstraction of Java servlets JSPs are

loaded in the server and are operated from a structured special installed Java server packet

called a Java EE Web Application, often packaged as a file archive.

JSP allows Java code and certain pre-defined actions to be interleaved with static web

markup content, with the resulting page being compiled and executed on the server to deliver

an HTML or XML document. The compiled pages and any dependent Java libraries use Javabytecode rather than a native software format, and must therefore be executed within a Java

virtual machine (JVM) that integrates with the host operating system to provide an abstract

platform-neutral environment.

JSP syntax is a fluid mix of two basic content forms:scriptlet elements and markup. Markup

is typically standard HTML or XML, while scriptlet elements are delimited blocks of Java

code which may be intermixed with the markup. When the page is requested the Java code is

executed and its output is added, in situ, with the surrounding markup to create the final page.

JSPs must be compiled to Java bytecode classes before they can be executed, but suchcompilation is needed only when a change to the source JSP file has occurred.

Java code is not required to be complete (self contained) within its scriptlet element block,

but can straddle markup content providing the page as a whole is syntactically correct (for

example, any Java if/for/while blocks opened in one scriptlet element must be correctly


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closed in a later element for the page to successfully compile). This system of split inline

coding sections is calledstep over scriptingbecause it can wrap around the static markup by

stepping over it. Markup which falls inside a split block of code is subject to that code, so

markup inside an ifblock will only appear in the output when the ifcondition evaluates to

true; likewise markup inside a loop construct may appear multiple times in the output

depending upon how many times the loop body runs.

The JSP syntax adds additional XML-like tags, called JSP actions, to invoke built-in

functionality. Additionally, the technology allows for the creation of JSP tag libraries that act

as extensions to the standard HTML or XML tags. JVM operated tag libraries provide

a platform independent way of extending the capabilities of a web server. Note that not all

commercial Java servers are Java EE specification compliant

ORACLE

DATABASE


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ORACLE DATABASE

ORACLE is a database vendor that uses to design relational database.

A database management system, or DBMS, gives the user access to their data

and helps them transform the data into information. Oracle allows users to

create, update, and extract information from their databases. Compared to a

manual filing system, the biggest advantages to a computerized database system

are speed, accuracy, and accessibility. A database is a structured collection of

data. Data refers to the characteristics of people, things, and events. Oracle

stores each data item in its ownfield. In Oracle, the fields relating to a particular

person, thing, or event are bundled together to form a single, complete unit of

data, called a record (it can also be referred to as a row or an occurrence). Each

record is made up of a number of fields. No two fields in a record can have the

same field name.

During an Oracle database design project, the analysis of our Business

needs identifies all the fields or attributes of interest.

If your business needs change over time, you define any additional fields

or change the definition of existing fields.

ORACLE TABLE


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Oracle stores records relating to each other in a table. A table is easily

visualized as a tabular arrangement of data, not unlike a spreadsheet, consisting

of vertical columns and horizontal rows. A table consists of a number of

records. The field names of each record in the table are the same, although the

field values may differ. Each field occupies one column and each record

occupies one row. Each record is a unique entry and is Independent of any other

record in the table. After the analysis of the business requirements, the database

design team defines the necessary tables. Different tables are created for the

various groups of information Related tables are grouped together to form a

database.


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DATABASE MANGEMENT SYSTEM

Database :- Storage of data in large quantity

Management :- database handling activties

Creation of database

Adding data to the datbase

Modifying database to the database

Removing data from database Accessing data from database

System :- a complex program or software

Complex sowftware that [performs management activities like

creation,addition of data modifying ,removing data on a database is

called as database management system .


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INTEGRITY RULES

Integrity rules are needed to inform the DBMS about certain constraints

in the real world.

Specific integrity rules apply to one specific database.

Example: part weights must be greater than zero.

General integrity rules apply to all databases.

Two general rules will be discussed to deal with: primary keys and foreignkeys.

PRIMARY KEYS

Primary key is a unique identifier for a relation.

There could be several candidate keys, as long as the they satisfy two

properties:

1. uniqueness

2. minimality

From the set of candidate keys, one is chosen to be the primary key.

The others become alternate keys.

EXAMPLE: The relation R has several candidate keys.

ID SSN License_Number NAME

If we select ID to be the primary key, then the other candidate keys

become alternate keys.

THE ENTITY INTEGRITY RULE

No component of the primary key of a base relation is allowed to accept

nulls.


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WHAT ARE NULLS?

Null may mean "property does not apply". For example, the supplier may

be a country, in which case the attribute CITY has a null value because

such property does not apply.

Null may mean "value is unknown". For example, if the supplier is aperson, then a null value for CITY attribute means we do not know the

location of this supplier.

Nulls cannot be in primary keys, but can be in alternate keys.

EXAMPLE: SSN may be null for one and only one person (why?)

FOREIGN KEYS

A foreign key is an attribute of one relation R2, whose

values are required to match those of the primary key of some

other relation R1 (R1 and R2 can be identical)

EXAMPLE: SP relation has attribute S#, and S relation hasprimary key S#. Then S# in SP is considered a foreign key.

REFERENTIAL INTEGRITY RULE

EXAMPLE: The three 3NF relations are:

SP(S#,P#,QTY)

SC(S#,CITY)

CS(CITY,STATUS)

The referential diagrams are:

SP ---S#---> SC ---CITY---> CS

DELETE INTEGRITY RULE:We should not delete (S5,London) from SC if S5 is present in

SP.

INSERT INTEGRITY RULE:

We should not insert (S3,P2,200) into SP unless S3 is present


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in SC.


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FEASIBILITY

ANALYSIS

FEASIBILITY STUDY

Feasibility studies aim to objectively and rationally uncover the strengths and

weaknesses of the existing business or proposed venture, opportunities and

threats as presented by the environment, the resources required to carry through,

and ultimately the prospects for success. In its simplest term, the two criteria to

judge feasibility are cost required and value to be attained. As such, a well-

designed feasibility study should provide a historical background of the


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business or project, description of the product or service, accounting statements,

details of the operations and management, marketing research and policies,

financial data, legal requirements and tax obligations. Generally, feasibility

studies precede technical development and project implementation.

Five common factors (TELOS)

Technology and system feasibility

The assessment is based on an outline design of system requirements in terms of

Input, Processes, Output, Fields, Programs, and Procedures. This can be

quantified in terms of volumes of data, trends, frequency of updating, etc. in

order to estimate whether the new system will perform adequately or not.

Technological feasibility is carried out to determine whether the company has

the capability, in terms of software, hardware, personnel and expertise, to

handle the completion of the project.

In our project we usejava in which we use Servlets, java server page Java

Beans, Database Connectivity. Oracle 10 g for database.

ECONOMIC FEASIBILITY

Economic analysis is the most frequently used method for evaluating theeffectiveness of a new system. More commonly known as cost/benefit analysis,

the procedure is to determine the benefits and savings that are expected from a

candidate system and compare them with costs. If benefits outweigh costs, then

the decision is made to design and implement the system. An entrepreneur must

accurately weigh the cost versus benefits before taking an action.

Cost-based study: It is important to identify cost and benefit factors, which can

be categorized as follows: 1. Development costs; and 2. Operating costs. This is

an analysis of the costs to be incurred in the system and the benefits derivable

out of the system.


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Time-based study: This is an analysis of the time required to achieve a return on

investments. The future value of a project is also a factor.

In our project the software which we use for develop our project is totally freeeither it is java, Oracle 10 g. So there is no economically cost.

LEGAL FEASIBILITY

Determines whether the proposed system conflicts with legal requirements, e.g.A data processing system must comply with the local Data Protection Acts.

Since all the software we are using is free, so we are not violating any anti

piracy law.

OPERATIONAL FEASIBILITY

Operational feasibility is a measure of how well a proposed system solves the

problems, and takes advantage of the opportunities identified during scope

definition and how it satisfies the requirements identified in the requirements

analysis phase of system development. This software fulfill all the needs of car

showroom departmental stores.

SCHEDULE FEASIBILITY

A project will fail if it takes too long to be completed before it is useful.

Typically this means estimating how long the system will take to develop, and if

it can be completed in a given time period using some methods like payback

period. Schedule feasibility is a measure of how reasonable the project timetable

is. Given our technical expertise, are the project deadlines reasonable? Some


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projects are initiated with specific deadlines. You need to determine whether the

deadlines are mandatory or desirable.

Since, we are using rapid development tools . Therefore the software will beeasily completed on schedule.

HARDWARE

REQUIREMENTS


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HARDWARE REQUIREMENT

1.PROCESSOR :-

PENTIUM(ANY) OR DAUL (CORE)

2. RAM :-512 MB+

3. HARD DISK:-

SATA 40 GB OR ABOVE

4.MONITOR 14.1 OR 15-17 INCH

5.KEYBOARD ,MOUSE


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SOFTWARE

REQUIREMENTS


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SOFTWARE REQUIREMENTS

OPERATING SYSTEM :-

WINDOWS 7,

WINDOWS XP AND HIEHGER

JSP(JAVA SERVER PAGE)

ORACLE 10g


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DATA FLOW

DAIGRAM

DATA FLOW DAIGRAMA data flow diagram is graphic representation of the flow of data through

business functions or processes. More generally, a data flow diagram is used for

visualization and data processing. It illustrates the process, data stores, and


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external entities, data flows in a business or other system and the relationships

between these things. Physical DFDs represent physical files and transactions,

or while logical or conceptual DFDs can be used to represent business functions

or processes. DFDs can be of an existing system, or can describe the

requirements for a proposed or planned system. A DFD of an existing system

should represent the functions and processes that are already in place, flaws and

all. A required system DFD is a diagram of a system that will be implemented

in the place of the current one, The data flow diagram shows the flow of data or

information. It can be partitioned into single processes or functions. Data flow

diagrams can be grouped together of decomposed into multiple processes. There

can be physical DFD s that represents the physical files and transactions, or they

can be business DFD (aka logical, or conceptual).

When it is used

This is an excellent communication tool for analysts to model

processes and functional requirements. One of the primary tools ofthe structured analysis efforts of the 1970s it was developed and

enhanced by the likes of Yourdon, McMenamink, Palmer, Gane and

Sarson. It is still considered one of the best modeling techniques for

eliciting and representing the processing requirements of a system.

Used effectively, it is useful and easy to understand modeling tool. It

has broad application and usability across most software

development projects. It is easily integrated with data modeling,

word flow modeling tool, and textual specs. Together with these, it

provides analysts and developers with solid models and specs.

Alone, however, it has limited visibility. It is simple and easy to

understand by users and can be easily extended and refined with

further specification into a physical version for the design and the

development teams.


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DATA FLOW


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DIAGRAM

SYMBOLS

DATAFLOW DAIGRAM SYMBOL

Process


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Depending on the level of the diagram it may represent the whole

system as in a Context(level 0) diagram or a business area,

process(activity), function, etc. in lower levels.

Symbol: Circle or a rounded rectangle. In the physical model, a

program label is identified in the bottom of the symbol.

External Entity

Symbol: Rectangular box, which may be shaded. A person or group,

which interacts with the system. Something outside the system. It isnot a user.

Usually external to the business or the system but may be internal.

Data Store

A repository of information. In the physical model, this represents a

file, table, etc. In the logical model, a data store is an object or entity.

Symbol: Two parallel lines, or an open ended rectangle.

Entity


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Data Flows

The directional movement of data to and from External Entities, the

process and Data Stores. In the physical model, when it flows into a

data store, it means a write, update, delete, etc. flows out of Data

Stores, mean read, query, display, select types of transaction.

Symbol: Solid line with arrow. Each data flow is identified with a

descriptive name that represents the information ( data packet ) onthe data flow.


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0-LEVEL DATA

FLOW DIGRAM


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0-LEVEL DATA FLOW DIGRAM

Login Info Query

Acknowledgement Result

EXPLANATION OF 0 LEVELS

In the 0-level DFD a server is connect with client. First of all, client send

the request to the server for user authentication. Server sends response to

client authentication. If the authentication becomes successful then themessaging starts.

EducationalForum & Online

Messaging

S stem

CLIENT


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1-LEVEL DATA

FLOW DIGRAM


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1-LEVEL DATA FLOW DIGRAM

Login login process

Login DB

Login Status

Result Query/Answer

Query

Ans ID

Ans DB Psst Details

Query DB

Answer

LoginUSER

Query


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1.LEVEL DFD OFONLINE

MESSAGING

SYSTEM

1-LEVEL DFD OF ONLINE

MESSAGING SYSTEM


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EXPLANATION OF 1.LEVEL DFD OF

ONLINE MESSAGING SYSTEM

The First level DFD shows that one user is connected to the server and

server is connected to the user of the database and user sends the request

for authentication to the server and the server after verification server is

verification

USER

acknowledgement

USER LIST

MESSAGING

STA

RT

MAS

SEGI

NG

RESPONCEAcknowledge(

User

R

E

P

L

Y

Send

information

REPLY

Request(

authentication )

respon

serve

S

e

ar

c

h


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also send a response to user. And then server is connected to the user list

and check out the user when that use

T r is fount in user list then server send a request to the connecting with the

user connectivity. When this work is completed then user connectivitycheck the user-ID coming from the user side is new or old. When all above

process is completed, now any user can communicate with anyone present

in the user list and share the TEXT files.


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ENTITY

RELATIONSHIP

DIAGRAM

1

M

M

userpass

address

emaili

d

Phon

no.Login Table

Submit

query

Question

Qid

User

idQuery DataBase

Posted


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M

The Entity-Relationship Model

The Entity-Relationship (ER) model was originally proposed by Peter in 1976

as a way to unify the network and relational database views. Simply stated the

ER model is a conceptual data model that views the real world as entities and

relationships. A basic component of the model is the Entity-Relationship

diagram which is used to visually represent data objects. Since Chen wrote his

paper the model has been extended and today it is commonly used for database

design for the database designer, the utility of the ER model is:

1. It maps well to the relational model. The constructs used in the ER model can

easily be transformed into relational tables.

2. It is simple and easy to understand with a minimum of training. Therefore,

the model can be used by the database designer to communicate the design to

the end user.


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3. In addition, the model can be used as a design plan by the database developer

to implement a data model in specific database management software.

Basic Constructs of E-R Modeling

Entities

Entities are the principal data object about which information is to be collected.

Entities are usually recognizable concepts, either concrete or abstract, such as

person, places, things, or events which have relevance to the database. Some

specific examples of entities are EMPLOYEES, PROJECTS and

INFORMATION. An entity is analogous to a table in the relational model.

Entities are classified as independent or dependent (in some methodologies, the

terms used are strong and weak, respectively). An independent entity is one that

does not rely on another for identification. A dependent entity is one that relies

on another for identification. An entity occurrence (also called an instance) is an

individual occurrence of an entity. An occurrence is analogous to a row in the

relational table.

Relationships

Relationship represents an association between two or more entities.

Relationships are classified in terms of degree, connectivity, cardinality, and


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existence. These concepts will be discussed below.

Attributes

Attributes describe the entity of which they are associated. A particular instance

of an attribute is a value.The domain of an attribute is the collection of all

possible values an attribute can have. Attributes can be classified as identifiers

or descriptors. Identifiers, more commonly called keys, uniquely identify an

instance of an entity. A descriptor describes a non-unique characteristic of anentity instance.

Classifying Relationships

Relationships are classified by their degree, connectivity, cardinality, direction,

type, and existence.

Degree of a Relationship

The degree of a relationship is the number of entities associated with the

relationship. Then-aryrelationship is the general form for degree n. Special

cases are the binary, and ternary, where the degree is 2, and 3, respectively.

Binary relationships, the association between two entities are the most common

type in the real world. A recursive binary relationship occurs when an entity is

related to itself. A ternary relationship involves three entities and is used when a

binary relationship is inadequate. Many modeling approaches recognize only

binary relationships. Ternary or n-ary relationships are decomposed into two or

more binary relationships.

Direction


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The direction of a relationship indicates the originating entity of a binary

relationship. The entity from which a relationship originates is the parent entity;

the entity where the relationship terminates is the child entity. The direction of a

relationship is determined by its connectivity. In a one-to- one relationship the

direction is from the independent entity to a dependent entity. If both entities are

independent, the direction is arbitrary. With one- to-many relationships, the

entity occurring once is the parent. The direction of many-to-many relationships

is arbitrary.

ER Notation

There is no standard for representing data objects in ER diagrams. Each

modeling methodology uses its own notation. The original notation used by

Chen is widely used in academics texts and journals but rarely seen in either

CASE tools or publications by non-academics. Today, there are a number of

notations used, among the more common are Bachman, crow's foot, and

IDEFIX. All notational styles represent entities as rectangular boxes and

relationships as lines connecting boxes. Each style uses a special set of symbols

to represent the cardinality of a connection. The notation used in this document

is from Martin.

The symbols for basic ER constructs

Entities are represented by labeled rectangles.

The label is the name of the entity. Entity names should be singular

nouns.Relationships are represented by a solid line connecting two entities. The

name of the relationship is written above the line. Relationship names should be

verbs.Attributes, when included, are listed inside the entity rectangle. Attributes

which are identifiers are underlined. Attribute names should be singular nouns.

Cardinality of many is represented by a line ending in a crow's foot. If the


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crow's foot is omitted, the cardinality is one.Existence is represented by placing

a circle or a perpendicular bar on the line. Mandatory existence is shown by the

bar (looks like a 1) next to the entity for an instance is required. Optional

existence is shown by placing a circle next to the entity that is optional.

ER DIAGRAM


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There are various object based models the most widely used Entity

Relationships model. It is accepted as the ideal data model in 1976 and since

then several people have added value to its. The ER model is based on the real

world perception that comprises a collection of object objects or entities and the

relationship among these.

The ER diagram is a diagramming techniques. The ER diagram consists the

three following parts.

ENTITIES

RELATIONSHIPS

ATTRIBUTES

ENTITIES

An entities is define as a thing which can be easily identify an entities is anyobject, place, person etc.

Example of an entities are student, courses, mango etc.

RELATIONSHIPS

A relationship is defines as an association among entities or in other word link

between entities.

Example There is a relationship (teach) between student and teacher.

TYPE OF RELATIONSHIP

One to one

One to many(or many to one)

Many to many


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ATTRIBUTES

An attribute is a property of a given entity.

Example Roll no. is a property of an entity of student.

An attribute instance is a particular property of an individual entity


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CONCLUSION

Conclusion

The project edcauational forum and online messaging system ,

The Educational Forum is targeted toward educators, from classroom teachers

to college/university professors, theorists, researchers, graduate-level students,

and policy makers.

The Educational Forum intends to serve as a catalyst for stimulating and

encouraging dialogue and for transforming the thinking about education.

Online messaging system refers to the casual chat between the two or more

users.


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FUTURE


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ENHANCEMENT

FUTURE ENHANCEMENT

The project(educational forum and online messaging system ) is generalized

software and can be easily used. The change in software can be easily

accommodated. The addition and deletion of the modules in software can be

easily adjusted .the software can be enhanced up to any legal extent depending

upon clients requirement.


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BIBLIOGRPHY


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BIBLIOGRAPHYThese are the following links which assist me at each and every step in

completing this project.

1. www.wikipedia.com

2. www.answers.com

3. www.askme.com

Instead of these useful website, following books also help me:

1. Object Oriented Programming with JAVA by

Khalid Mughal.

2. Black Books(J2SE, J2EE).

3. Oracle(Complete Reference).
http://www.wikipedia.com/http://www.wikipedia.com/http://www.answers.com/http://www.answers.com/http://www.askme.com/http://www.askme.com/http://www.askme.com/http://www.answers.com/http://www.wikipedia.com/

Documents

Educational Forum & Online Mesging System Bca