MATERIAL GATE PASS SYSTEM
INDEXABSTRACT
Introduction
Introduction to Project
Introduction to Organization
System Analyses
Introduction
Existing System
Proposed System
Feasibility Study
System Requirement
Introduction
Functional Requirements
System Requirements
Software Requirements
Hardware Requirements
System Design
Introduction
High Level Design
System Design
Subsystem Design
Block Design
Low Level Design
UML Diagrams
Data Flow Diagrams
Use case Diagrams
Sequence Diagrams
Class Diagrams
Object Diagrams
Activity Diagrams
State chart Diagrams
Activity Diagrams
Collaboration Diagrams
Component Diagrams
Deployment Diagrams
Coding
Testing
Screen Shots
Conclusion
BibliographyABSTRACTThis Project Drug Order Management System is
a solution to Aurobindo Pharma to take the orders from its
distributors who are geographically distributed. This new system
not only takes the orders from distributors for Aurobindo Pharma
but it also facilities.The administration, as well as the report
generation for the firm.Each user of this system is given a unique
id and password along with some Information for our report
generation, and administration. Later the user id will be used for
his identification. The system maintains vendors, category of
products they are supplying, products under each category,
discount, and payment modes such as DD, Cheque, and online payment
mode Credit Card. This system also maintains the order details, to
provide the valuable reports regarding sales to the organization
whenever they want. Here we are providing the administration part
too for the organization.This system provides information entered
but also analyzes data. Each users details are kept private and no
other body can tinker with them.
Existing System
1. In this we could store the data manually.2. In the existing
system data storing was not so easy.
3. Retrieving data is very difficult.
Proposed System
The proposed system can be accessed from any part of the world,
as opposed to stand alone or manual system, and provides
information at any time, anywhere.
Even though it is a web-based application it will keep the
details of its clients private and no body is allowed to tinker
with the details.
No need to own any computer for this specific ordering of
products, it just requires user to register with the system.It
provides easy to use and user friendly interface for the user.
The organization people can do administration over the products,
vendor, customer (only deletion in case of dealer ship
cancellation) etc.
Modules1. Administration Module2. Reports Module3. EndUser
Module4. WebUserInterface Module.
Administration ModuleIn this module admin can add product
details, vendors details,category details,discount details,stock
detals and view customer details.And also he could update,delete
the product, vendors,category details,discount details,stock
details.Reports Module
In this module we could view all the information regarding like
how many number of customers, vendors.We can view differerent
catogaries of products.we could view different discount details and
also we view stock details.EndUser Module
In this module customers send orders for products to
admin.WebUserInterfaceWeb user Interface will provide the interface
to the user to communicate with the system.
System Specifications
Software Requirements
Operating System
:
Windows XP
User Interface
:
HTML, CSS
Client-side Scripting
:
JavaScript
Programming Language
:
Java
Web Applications
:
JDBC, Servlets, JSP
Database
:
Mysql
Server Deployment
:
Apache Tomcat
Hardware Requirements
Processor
:
Pentium IV
Hard Disk
:
160GB
RAM
:
1GB
Process flow Diagram or architecture Diagram
Introduction
This Project Drug Order Management System is a solution to
Aurobindo Pharma to take the orders from its distributors who are
geographically distributed. This new system not only takes the
orders from distributors for Aurobindo Pharma but it also
facilities.The administration, as well as the report generation for
the firm.
Each user of this system is given a unique id and password along
with some Information for our report generation, and
administration. Later the user id will be used for his
identification. The system maintains vendors, category of products
they are supplying, products under each category, discount, and
payment modes such as DD, Cheque, and online payment mode Credit
Card. This system also maintains the order details, to provide the
valuable reports regarding sales to the organization whenever they
want. Here we are providing the administration part too for the
organization.This system provides information entered but also
analyzes data. Each users details are kept private and no other
body can tinker with them.
INTRODUCTION TO ORGANIZATIONNeoApp ProfileNeoApp develops custom
software solutions for companies in a variety of industries. Since
its beginning in August 2008, NeoApp has offered efficient,
reliable and cost-effective solutions with good quality by
implementing CMMI practices from its development facility located
at Hyderabad.
NeoApp has expertise in latest technologies and caters to your
exacting requirements. NeoApp helps you from concept to completion
of a project with full range of service offerings.
Most importantly, NeoApp combines the right strategy with the
right products and the right people, ensuring technical
superiority, high quality deliverables and timely implementations.
NeoApp supports different delivery and billing models to fit your
requirements. By having NeoApp involved with your software
development projects, you benefit with reduced costs and faster
development cycles. To reduce the development costs NeoApp strictly
adhere on reusable component model with plug and play
architecture.
Offshore outsourcing model became easily adoptable and has
increased benefits beyond cost reductions. The offshore outsourcing
with NeoApp includes full spectrum services and multi fold
benefits.
NeoApp, with its experience in executing offshore projects
ranging from large enterprise solutions to small plug-in
applications, helps customers achieve the offshore outsourcing
goals.
NeoApp establishes suitable project execution methodologies for
each project and accomplishes offshore execution on time and on
budget. NeoApp pays high importance to quality of deliverables and
has mandatory quality doors in place for each project ensuring
success of the overall project.
NeoApp works with you from conceptualization to completion and
has the required expertise to pick up the project at any stage in
its life cycle.
1. Business concept and system study
2. Requirement Study
3. Design Architecture and develop specifications
4. Design the framework of the solution
5. Develop the solution
6. QA the solution against requirements
7. Continuous support for the solution
8. Develop prototypes for proof of concept
9. Engineer the solution
10. Release as per plan
The team and project approach of NeoApp has resulted in above
expected deliveries of projects. NeoApp works with you in refining
the project at every stage and with its vast and experienced talent
pool, NeoApp brings value with innovation to the project.
NeoApp offers complete solutions to application maintenance
requirements helping organizations to cut costs and optimize
resource utilization. NeoApp performs the following tasks on a
variety of technology platforms beginning with Legacy to Client
Server to Browser based internet application.
1. Application Development
2. Application Maintenance
3. Application Support
NeoApp with its experience in wide range technologies and
ability to learn quickly help you ensuring availability of your
systems to your customers. NeoApp performs systems monitoring and
undertakes evolutionary development of these applications as
required and deemed fit.SYSTEM ANALASYS
Analysis is the process of understanding the existing system by
gathering and interpreting the facts, diagnosing the problems. It
is not just to determining the how best to solve the manual system
problems, it should also work for the system observes the
feasibility of system then design, coding phases will be executed.
Analysis phase delivers requirements specification .The system
specification serves as an interface between the designer and
developer as well as between developers and users. This describes
the external behavior of the software without bothering about the
internal implementation. Specification must be carefully checked
for suitability, omission, inconsistencies and ambiguities.
Problem analysis is performed to getting a clear understanding
of the needs of the clients and the users and what exactly desired
form the software. Analysis leads to the actual specification.
During the process of analysis, a massive amount of information is
collected in the form of interviews, questionnaires, and
information from documentation, and so forth. The major problem
during analysis is resolving how to organize the information from
documentation, and so forth. So the information can be effectively
evaluated for completeness and consistency.
Existing System
4. In this we could store the data manually.
5. In the existing system data storing was not so easy.
6. Retrieving data is very difficult.
Proposed System
The proposed system can be accessed from any part of the world,
as opposed to stand alone or manual system, and provides
information at any time, anywhere.
Even though it is a web-based application it will keep the
details of its clients private and no body is allowed to tinker
with the details.
No need to own any computer for this specific ordering of
products, it just requires user to register with the system.It
provides easy to use and user friendly interface for the user.
The organization people can do administration over the products,
vendor, customer (only deletion in case of dealer ship
cancellation) etc.
FEASIBILITY STUDYAll projects are feasible given unlimited
resources and infinite time! Unfortunately, the development of
computer-based system or product is more likely plagued by a
scarcity of resources and difficult delivery dates. It is both
necessary and prudent to evaluate the feasibility of a project at
the earliest possible time. Months or years of effort, thousands or
millions of dollars, and untold professional embarrassment can be
averted if an ill-conceived system is recognized early in the
definition phase.
Feasibility and risk analysis are related in many ways. If
project risk is great the feasibility of producing quality software
is reduced. During product engineering, however, we concentrate our
attention on four primary areas of interestTechnical
Feasibility
This application in going to be used in an Internet environment
called www (World wide web). So, it is necessary to use a
technology that is capable of providing the networking facility to
the application. This application as also able to work on
distributed environment. Application on developed with J2EE (Java 2
Enterprise Edition platform) Technology. One major advantage in
application is platform neutral. We can deploy and used it in any
operating system.
GUI is developed using HTML.to capture the information from the
customer. HTML is used to display the content on the browser. It
uses TCP/IP protocol. It is an interpreted language. It is very
easy to develop a page/document using HTML some RAD(Rapid
Application Development) tools are provided to quickly
design/develop our application. So many objects such as button,
text fields, and text area etc are provide to capture the
information from the customer.
We can use this application in any OS. They can have their own
security and transactional advantages. But are the responsible for
selecting suitable and secured OS, which is suitable to our
application.
The back-end Oracle 8i and front-end application are platform
independent. So we can port this enterprise application in any
environment. Both are having their individual configuration to get
better performance and backup issues.
Economical Feasibility
In present system customer need to go to billers place to pay
the bill. So he/she needs to spend some time to complete this
protocol. It is time consuming process some times customer not able
to spend that much of time. In such case needs to pay some
additional payment to the biller for late payment.
If it is developed in electronic payment system, He can pay the
bill from any where in the world. No need to travel to pay the
bills. For doing this process electronically have to spend some
time.
Operational FeasibilityIn our application front end is developed
using GUI. So it is very easy to the customer to enter the
necessary information. But customer has some knowledge on using web
applications before going to use our application.
SYSTEM REQUIREMENTSINTODUCTION
Software Requirements Specification plays an important role in
creating quality software solutions. Specification is basically a
representation process. Requirements are represented in a manner
that ultimately leads to successful software implementation.
Requirements may be specified in a variety of ways. However there
are some guidelines worth following: -
Representation format and content should be relevant to the
problem
Information contained within the specification should be
nested
Diagrams and other notational forms should be restricted in
number and consistent in use.
Representations should be revisable.
The software requirements specification is produced at the
culmination of the analysis task. The function and performance
allocated to the software as a part of system engineering are
refined by establishing a complete information description, a
detailed functional and behavioral description, and indication of
performance requirements and design constraints, appropriate
validation criteria and other data pertinent to requirements.
Functional RequirementsThis section contains specification of
all the functional requirements needed to develop this module or
sub-module.
Requirement IDRequirement SpecificationPriority
(A/B/C)
DOMS_01System should provide a provision for admin to login.
DOMS_02System should provide a provision for admin to add
product details.
DOMS_03System should provide a provision for admin to update
product details.
DOMS_04System should provide a provision for admin to delete
product details.
DOMS_05System should provide a provision for admin to view
customers details.
DOMS_06System should provide a provision for admin to delete
customers details.
DOMS_07System should provide a provision for admin to add
vendors details.
DOMS_08System should provide a provision for admin to update
vendors details.
DOMS_09System should provide a provision for admin to delete
vendors details.
DOMS_10System should provide a provision for admin to add
catogery details.
DOMS_11System should provide a provision for admin to update
catogery details.
DOMS_12System should provide a provision for admin to delete
catogery details.
DOMS_13System should provide a provision for admin to add
discount details.
DOMS_14System should provide a provision for admin to update
discount details.
DOMS_15System should provide a provision for admin to delete
discount details.
DOMS_16System should provide a provision for admin to add stock
details.
DOMS_17System should provide a provision for admin to update
stock details.
DOMS_18System should provide a provision for admin to add stock
details.
DOMS_19System should provide a provision for admin to view
product details.
DOMS_20
System should provide a provision for admin to view order
details
DOMS_21System should provide a provision for admin to view
catogery details.
DOMS_22System should provide a provision for admin to view
discount details.
DOMS_23System should provide a provision for admin to view
vendors details.
DOMS_24System should provide a provision for admin to view
registration details.
DOMS_25System should provide a provision for enduser to
registration.
DOMS_26System should provide a provision for enduser to
login.
DOMS_27System should provide a provision for enduser to send
order details to the admin.
DOMS_28System should provide a provision for end user to
logout.
DOMS_29System should provide a provision for admin to
logout.
Non-Functional RequirementsUsability: Usability is the ease of
use and learns ability of a human-made object. The object of use
can be a software application, website, book, tool, machine,
process, or anything a human interacts with. A usability study may
be conducted as a primary job function by a usability analyst or as
a secondary job function by designers, technical writers, marketing
personnel, and others.
Reliability: The probability that a component part, equipment,
or system will satisfactorily perform its intended function under
given circumstances, such as environmental conditions, limitations
as to operating time, and frequently and thoroughness of
maintenance for a specified period of time.
Performance: Accomplishment of a given task measured against
preset standards of accuracy, completeness, cost, and speed.
Supportability: To which the design characteristics of a stand
by or support system meet the operational requirements of an
organization.
Implementation: Implementation is the realization of an
application, or execution of a plan, idea, model, design,
specification, standard, algorithm, or policy.
Interface: An interface refers to a point of interaction between
components, and is applicable at the level of both hardware and
software. This allows a component whether a piece of hardware such
as a graphics card or a piece of software such as an internet
browser to function independently while using interfaces to
communicate with other components via an input/output system and an
associated protocol.
Legal: It is established by or founded upon law or official or
accepted rules of or relating to jurisprudence; legal loophole.
Having legal efficacy or force, a sound title to the
property
Relating to or characteristic of the profession of law, the
legal profession.
Allowed by official rules; a legal pass receiver.
Software Requirements Operating System
:
Windows XP
User Interface
:
HTML, CSS
Client-side Scripting
:
JavaScript
Programming Language
:
Java
Web Applications
:
JDBC, Servlets, JSP
Database
:
Mysql
Server Deployment
:
Apache Tomcat
Hardware Requirements
Processor
:
Pentium IV
Hard Disk
:
160GB
RAM
:
1GB
DESIGNDESIGN SPECIFICATION
Design of software involves conceiving planning out and
specifying the externally observable characteristics of the
software product. We have data design, architectural design and
user interface design in the design process. These are explained in
the following section. The goals of design process it to provide a
blue print for implementation, testing, and maintenance
activities.
DATA DESIGN
The primary activity during data design is to select logical
representations of data objects identified during requirement
analysis and software analysis. A data dictionary explicitly on the
elements of the data structure. A data dictionary should be
established and used to define both data and program design.
DESIGN METHODOLOGY
The two basic modern design strategies employed in software
design are
Top Down Design
Bottom Up Design
Top Down Design is basically a decomposition process, which
focuses on the flow of control. At later stages it concern itself
with the code production. The first step is to study the overall
aspects of the tasks at hand and to break it into a number of
independent modules. The second step is to break each one of these
modules further into independent sub-modules. The process is
Repeated one to obtain modules, which are small enough to group
mentally and to code in a straightforward manner. One important
feature is that at each level the details of the design at the
lower level are hidden. Only the necessary data and control that
must be called back and forth over the interface are defined.
In a bottom-up design one first identifies and investigates
parts of design that are most difficult and necessary designed
decision are made the reminder of the design is tailored to fit
around the design already chose for crucial part. It vaguely
represents a synthesis process explained in previous section.
One storage point of the top-down method is that it postpones
details of the decision until the last stage of the decision. It
allows making small design changes when the design is half way
through. There is danger that the specifications will be
incompatible and this will not be discovered until late in the
design process. By contrast the bottom-up strategy first focuses on
the crucial part so that feasibility of the design is tested at
early stage.
In mixing top-down and bottom-up design it often appears that we
start in the middle of the problem and work our way both up and
down there. In a complex problem, it is often difficult to decide
how to modularize the various procedures in such cases one might
consider a list of system inputs and decide what functions are
necessary to process these inputs. This is called back to front
design. Similarly one can start with the required outputs and work
backwards evolving so called front-back design. We have applied
both the top down and bottom up approach in our design
approach.
DATABASE DESIGN
Databases are normally implemented by using a package called a
Data Base Management System (DBMS). Each particular DBMS has
somewhat unique characteristics, and so such, general techniques
for the design of database are limited. One of the most useful
methods of analyzing the data required by the system for the data
dictionary has developed from research into relational database,
particularly the work of E.F.Codd. this method of analyzing data is
called Normalization. Unnormalized data are converted into
normalized data by three stages. Each stage has a procedure to
follow.
NORMALIZATION
The first stage is normalization is to reduce the data to its
first normal form, by removing repeating items showing them as
separate records but including in them the key fields of the
original record.
The next stage of reduction to the second normal form is to
check that the record, which one is first normal form, all the
items in each record are entirely dependent on the key of the
record. If a data item is not dependent on the key of the record,
but on the other data item, then it is removed with its key to form
another record. This is done until each record contains data items,
which are entirely dependent on the key of their record.
The final stage of the analysis, the reduction of third normal
form involves examining each record, which one is in second normal
form to see whether any items are mutually dependent. If there are
any item there are removed to a separate record leaving one of the
items behind in the original record and using that as the key in
the newly created record.
BUSINESS MODELING:
The information flow among business function is modeled in a way
that answers the following questions: what information drives the
business process? What information is generated? What generate it?
Where does the information go? Who process it?
DATA MODELING:
The information flow defined as a process of the business
modeling is refined into a set of data objects that are needed to
support the business. The characteristics 9called attributes0 of
each object are identified and relationships between these objects
are defined.
PROCESS MODELING:
The data objects defined in the data-modeling phase are
transformed to achieve the information flow necessary to implement
a business function. Processing description is created for
addition, modifying, deleting, or retrieving a data object.
OBJECT DESIGN
During the object design, we fill the gap between the
application objects and the off-the-self components, which provide
a high level abstraction. It is done by identifying additional
solution objects and refining the existing objects.
Reusing Pattern Solutions:Application objects also called domain
objects, represent concepts of the domain that are relevant to the
system. Solution objects represent components that dont have a
counterpart in the application part domain, such as persistent data
stores, user interface objects, or middleware.
Specification inheritance and implementation:
The focus of inheritance during Object Design is on Redundancy
reduction and enhancement of extensibility. The implementation of
inheritance for the sole purpose of reusing the code is known as
Implementation inheritance, by which we reuse code quickly by sub
classing an existing class and refining its behavior.
INPUT DESIGN
The input design is the link between the information system and
the user. It comprises the developing specification and procedures
for data preparation and those steps are necessary to put
transaction data in to a usable form for processing can be achieved
by inspecting the computer to read data from a written or printed
document or it can occur by having people keying the data directly
into the system. The design of input focuses on controlling the
amount of input required, controlling the errors, avoiding delay,
avoiding extra steps and keeping the process simple. The input is
designed in such a way so that it provides security and ease of use
with retaining the privacy. Input Design considered the following
things:
What data should be given as input?
How the data should be arranged or coded?
The dialog to guide the operating personnel in providing
input.
Methods for preparing input validations and steps to follow when
error occur.
OBJECTIVES
1.Input Design is the process of converting a user-oriented
description of the input into a computer-based system. This design
is important to avoid errors in the data input process and show the
correct direction to the management for getting correct information
from the computerized system.
2. It is achieved by creating user-friendly screens for the data
entry to handle large volume of data. The goal of designing input
is to make data entry easier and to be free from errors. The data
entry screen is designed in such a way that all the data
manipulates can be performed. It also provides record viewing
facilities.
3.When the data is entered it will check for its validity. Data
can be entered with the help of screens. Appropriate messages are
provided as when needed so that the user will not be in maize of
instant. Thus the objective of input design is to create an input
layout that is easy to follow.
OUTPUT DESIGN
A quality output is one, which meets the requirements of the end
user and presents the information clearly. In any system results of
processing are communicated to the users and to other system
through outputs. In output design it is determined how the
information is to be displaced for immediate need and also the hard
copy output. It is the most important and direct source information
to the user. Efficient and intelligent output design improves the
systems relationship to help user decision-making.
1. Designing computer output should proceed in an organized,
well thought out manner; the right output must be developed while
ensuring that each output element is designed so that people will
find the system can use easily and effectively. When analysis
design computer output, they should Identify the specific output
that is needed to meet the requirements.
2. Select methods for presenting information.
3. Create document, report, or other formats that contain
information produced by the system.
The output form of an information system should accomplish one
or more of the following objectives.
Convey information about past activities, current status or
projections of the
Future.
Signal important events, opportunities, problems, or
warnings.
Trigger an action.
Confirm an action.
High Level DesignSystem Design
Understanding bigger application with its external interfaces is
called System Design.
Sub System Design:
Understanding bigger system into smaller independent working
systems is called subsystem design.
Block Design
In this application each and every user must having their own
User ID and Password, using these User ID and Password only they
can directly enter into their corresponding Login forms.
After enter into their Login forms each user will interact with
the following functionalities.
But according to their responsibilities only they will use the
above functionalities.
WUI (Web User Interface)
Web user Interface will provide the interface to the user to
communicate with the system.
DB Storage
This block helps us to store the data or retrieve the data from
database.
Administration Block
In this module admin can add product details,vendors
details,category details,discount details,stock detals.And also he
could update,delete the product,vendors,category details,discount
details,stock details.
Reports Block
In this module we could view all the information regarding like
how many number of customers, vendors.We can view differerent
catogaries of products.we could view different discount details and
also we view stock details.
EndUser Block
In this module customers send orders for products to admin.
Uml Diagrams
Data Flow Diagrams
The data flow diagram is used for classifying system
requirements to major transformation that will become programs in
system design. This is starting point of the design phase that
functionally decomposes the required specifications down to the
lower level of details. It consists of a series of bubbles joined
together by lines.Bubbles: Represent the data transformations.
Lines: Represents the logic flow of data.
Data can trigger events and can be processed to useful
information. System analysis recognizes the central goal of data in
organizations. This dataflow analysis tells a great deal about
organization objectives are accomplished.Dataflow analysis studies
the use of data in each activity. It documents this finding in
DFDs. Dataflow analysis give the activities of a system from the
viewpoint of data where it originates how they are used or hanged
or where they go, including the stops along the way from their
destination. The components of dataflow strategy span both
requirements determination and systems design. The first part is
called dataflow analysis.
As the name suggests, we didnt use the dataflow analysis tools
exclusively for the analysis stage but also in the designing phase
with documentation.NOTATIONS USED IN DATA FLOW DIAGRAMS
The logic dataflow diagrams can be drawn using only four simple
notations i.e., special symbols or icons and the annotation that
associates them with a specific system. Since the choice of
notation we follow, does not affect impede or catalyze the system
process; we used three symbols from YOURDON notation and one from
Gain and Sarson notation as specified below.
Element References symbols
Data Flow Process
Process
Data Store
Source or Sink
Description:
Process: describes how input data is converted to output
data
Data Store: Describes the repositories of data in a system
Data Flow: Describes the data flowing between process, Data
stores and external entities.
Sources: An external entity causing the origin of data.
Sink: An external entity, which consumes the data.
Context Diagram
The top-level diagram is often called a context diagram. It
contains a single process, but it plays a very important role in
studying the current system. The context diagram defines the system
that will be studied in the sense that it determines the
boundaries. Anything that is not inside the process identified in
the context diagram will not be part of the system study. It
represents the entire software element as a single bubble with
input and output data indicated by incoming and outgoing arrows
respectively.Types of data flow diagrams
DFDs are two types
1. Physical DFDSStructured analysis states that the current
system should be first understand correctly. The physical DFD is
the model of the current system and is used to ensure that the
current system has been clearly understood. Physical DFDs shows
actual devices, departments, people etc., involved in the current
system
2. Logical DFD
Logical DFDs are the model of the proposed system. They clearly
should show the requirements on which the new system should be
built. Later during design activity this is taken as the basis for
drawing the systems structure charts.
.
.
DATA FLOW DIAGRAMSCONTEXT LEVEL
LEVEL 1 DATA FLOW DIAGRAM
LEVEL 2 DATA FLOW DIAGRAM
LEVEL 2 DFD FOR PRODUCTS INFORMATION
Er diagram
6.iii. FLOW CHARTS
FLOW CHART FOR LOGIN DAILS
FLOW CHART FOR ADDING NEW PRODUCT
FLOW CHART FOR PRODUCT SELECTION
LowLevel DesignUseCase Diagrams
Sequence Diagrams
Communication Diagram
Class Diagram
Object Diagram
State Diagram
Activity Diagrams
Componet Diagram
Deployeement Diagram
Introduction
The Java web server is JavaSoft's own web Server. The Java web
server is just a part of a larger framework, intended to provide
you not just with a web server, but also with tools. To build
customized network servers for any Internet or Intranet
client/server system. Servlets are to a web server, how applets are
to the browser.
About Servlets
Servlets provide a Java-based solution used to address the
problems currently associated with doing server-side programming,
including inextensible scripting solutions, platform-specific APIs,
and incomplete interfaces.
Servlets are objects that conform to a specific interface that
can be plugged into a Java-based server. Servlets are to the
server-side what applets are to the client-side - object byte codes
that can be dynamically loaded off the net. They differ from
applets in that they are faceless objects (without graphics or a
GUI component). They serve as platform independent, dynamically
loadable, plugable helper byte code objects on the server side that
can be used to dynamically extend server-side functionality.
For example, an HTTP Servlets can be used to generate dynamic
HTML content. When you use Servlets to do dynamic content you get
the following advantages:
Theyre faster and cleaner than CGI scripts
They use a standard API (the Servlets API)
They provide all the advantages of Java (run on a variety of
servers without needing to be rewritten).
Attractiveness of Servlets
There are many features of Servlets that make them easy and
attractive to use. These include:
Easily configured using the GUI-based Administrator tool
Can be loaded and invoked from a local disk or remotely across
the network.
Can be linked together, or chained, so that one Servlets can
call another Servlets, or several Servlets in sequence.
Can be called dynamically from within HTML pages, using
server-side include tags.
Are secure - even when downloading across the network, the
Servlets security model and Servlets sandbox protect your system
from unfriendly behavior.
Advantages of the Servlet API
One of the great advantages of the Servlet API is protocol
independence. It assumes nothing about:
The protocol being used to transmit on the net
How it is loaded
The server environment it will be running in
These qualities are important, because it allows the Servlet API
to be embedded in many different kinds of servers. There are other
advantages to the Servlet API as well. These include:
Its extensible - you can inherit all your functionality from the
base classes made available to you.
it's simple, small, and easy to use.
Features of Servlets
Servlets are persistent. Servlet are loaded only by the web
server and can maintain services between requests.
Servlets are fast. Since Servlets only need to be loaded once,
they offer much better performance over their CGI counterparts.
Servlets are platform independent.
Servlets are extensible. Java is a robust, object-oriented
programming language, which easily can be extended to suit your
needs
Servlets are secure.
Servlets can be used with a variety of clients.
Loading Servlets
Servlets can be loaded from three places
From a directory that is on the CLASSPATH. The CLASSPATH of the
JavaWebServer includes service root/classes/ which is where the
system classes reside.
From the
