Classifieds

INTRODUCTION
ClassifiedsOnline is being launched because a need for a destination where the local community could come together and help each other is seen. Community members within a city can come here to find an apartment to live in, sell their old car, or music system, promote their small business, find a life partner, join a salsa class, find people who share their interests, get an audience for a local event, trade any item that they might want or have to offer and make new friends while doing all of the above.

PURPOSE:ClassifiedsOnline fulfills the requirements of an individual related to classifieds (situation vacant / buy n sell / matrimonial … and !ellow "ages. #t$s a destination where the local community could come together and help each other. % person can search for a house on rent without the involvement of a property dealer and save the e&tra money which he/she would have paid as commission. 'oreover, the person do all this in a single click of the mouse button i.e., searching / traversing ( posting advertisements etc. can be done while sitting at home.

)

What is ClassifiedsOnline all about?
ClassifiedsOnline is a web application that automatically matches posters of %*$s with potential viewers through a communication network in which a host system communicates with the "osters and "otential +iewers. ,he host system obtains and stores a first set of records each corresponding to a particular ad. ,his set of records can then be searched by a remote data terminal associated with a potential viewer. ,he results of this search are then provided to the potential poster, who indicates specific ad listings that the viewer may be interested in. ,he viewer provides identifying information which is then provided to the poster of the indicated ad. "rovisions are made to ensure that the ad posters who list ads support the system. -urther, the system permits automatic evaluation of potential viewers to screen posters whose information does not match minimum criteria. #t$s a system for selectively displaying ad listings to potential viewers and for obtaining ad viewer profile information associated with said potential viewers which is provided to ad posters of ad described in said ad listings.

ClassifiedsOnline provides the platform but does not directly participate in, nor is it involved in any Classifieds transactions. Classifieds are posted not by my system, but users of my system. 'y system requires a user to register before sending a quote. 'y system will send the information as filled in by the user on the form to registration for those who participate in a variety of its services. ,he system has an administrator who keeps an eye on the overall functioning of the system. ,he system gets revenue by displaying .anner %dvertisements which is done and controlled by the administrator. ,he system entitled / Classifieds0nline (0nline classifieds and !ellow "ages1 is application software, which aims at providing services to the local community and providing them with an option of selecting the %*$s of their choices and further decide to continue with the transaction. #t is developed by using 2344 technology and related database. require

3

OBJECTI E
,he summary of the objective of this software is to completely automate the process of5 6 6 "rovide better understanding between ad posters and its viewers. "rovide a user friendly environment so that the ad posters can post their ads easily and free of cost. 6 ,o maintain and store ad details, response details, ad viewers details, ad posters details 6 "rovide e&cellent and easy to access means of communication medium between ad posters and its viewers. 6 "rovide value to its contributors by making available to them its vast global audience reach 6 "rovide Classifieds as a service to enable its users to connect with one another. 6 "rovide local commerce site, uniquely integrating Classifieds and !ellow "ages. ,he system offers unmatched values such as 7eal 4state, ,ravels, jobs/,raining, 'ovies/4ntertainment, buy/sale, 'atrimonial and more.

8

INTRODUCTION TO TEC!NO"O#$

Int%odu&tion to J' ':
2ava is an object9oriented programming language with a built9in application programming interface (%"# that can handle graphics and user interfaces and that can be used to create applications or applets. .ecause of its rich set of %"#:s, similar to 'acintosh and ;indows, and its platform independence, 2ava can also be thought of as a platform in itself. 2ava also has standard libraries for doing mathematics. 'uch of the synta& of 2ava is the same as C and C<<. 0ne major difference is that 2ava does not have pointers. =owever, the biggest difference is that you must write object oriented code in 2ava. "rocedural pieces of code can only be embedded in objects. #n the following we assume that the reader has some familiarity with a programming language. #n particular, some familiarity with the synta& of C/C<< is useful. #n 2ava we distinguish between applications, which are programs that perform the same functions as those written in other programming languages, and applets, which are programs that can be embedded in a ;eb page and accessed over the #nternet. 0ur initial focus will be on writing applications. ;hen a program is compiled, a byte code is produced that can be read and e&ecuted by any platform that can run 2ava. ,he 2ava programming language consists out of a 2ava compiler, the 2ava virtual machine, and the 2ava class libraries. ,he 2ava virtual machine (2+' is a software implementation of a computer that e&ecutes programs like a real machine. ,he 2ava compiler translates 2ava coding into so9called byte9code. ,he 2ava virtual machine interprets this byte9code and runs the program. ,he 2ava virtual machine is written specifically for a specific operating system. ,he 2ava runtime environment (274 consists of the 2+' and the 2ava class libraries. ,here were five primary goals in the creation of the 2ava language5 ). #t should be >simple, object9oriented and familiar> 3. #t should be >robust and secure> 8. #t should be >architecture9neutral and portable> ?

?. #t should e&ecute with >high performance> @. #t should be >interpreted, threaded, and dynamic>

Cha%a&te%isti&s of Ja(a:Platfo%) inde*endent5 2ava programs use the 2ava virtual machine as abstraction and do not access the operating system directly. ,his makes 2ava programs highly portable. % 2ava program which is standard complaint and follows certain rules can run unmodified all several platforms, e.g. ;indows or Ainu&. Ob+e&t-o%ientated *%o,%a))in, lan,ua,e5 4&cept the primitive data types, all elements in 2ava are objects. St%on,l--t-*ed *%o,%a))in, lan,ua,e5 2ava is strongly9typed, e.g. the types of the used variables must be pre9defined and conversion to other objects is relatively strict, e.g. must be done in most cases by the programmer. Inte%*%eted and &o)*iled lan,ua,e5 2ava source code is transferred into byte9code which does not depend on the target platform. ,his byte9code will be interpreted by the 2ava +irtual machine (2+' . ,he 2+' contains a so called =otspot9Compiler which translates critical byte9code into native code. 'uto)ati& )e)o%- )ana,e)ent5 2ava manages the memory allocation and de9 allocation for creating new objects. ,he program does not have direct access to the memory. ,he so9called garbage collector deletes automatically object to which no active pointer e&ists.

Development with Java:,he programmer writes 2ava source code in a te&t editor which supports plain te&t. Bormally the programmer uses an IDE (integrated development environment for programming. %n #*4 support the programmer in the task of writing code, e.g. it provides auto9formatting of the source code, highlighting of the important keywords, etc. @

%t some point the programmer (or the #*4 calls the 2ava compiler (javac . ,he 2ava compiler creates platform independent code which is called bytecode. ,his byte9code is stored in >.class> files. .ytecode can be e&ecuted by the 2ava runtime environment. ,he 2ava runtime environment (274 is a program which knows how to run the bytecode on the operating system. ,he 274 translates the bytecode into native code and e&ecutes it, e.g. the native code for Ainu& is different than the native code for ;indows. "latform9independent 2ava is essential to the 2ava 44 strategy, and an even more rigorous validation is required to certify an implementation. ,his environment enables portable server9side applications, such as ;eb services, 2ava Cervlets, and 4nterprise 2ava.eans, as well as with embedded systems based on 0CDi, using 4mbedded 2ava environments. ,hrough the Dlass-ish project, Cun is working to create a fully functional, unified open source implementation of the 2ava 44 technologies.

B-te&ode e%ifie%
% basic philosophy of 2ava is that it is inherently safe from the standpoint that no user program can crash the host machine or otherwise interfere inappropriately with other operations on the host machine, and that it is possible to protect certain methods and data structures belonging to trusted code from access or corruption by untrusted code e&ecuting within the same 2+'. -urthermore, common programmer errors that often lead to data corruption or unpredictable behavior such as accessing off the end of an array or using an uninitialiEed pointer are not allowed to occur. Ceveral features of 2ava combine to provide this safety, including the class model, the garbage9collected heap, and the verifier. ,he 2+' verifies all bytecode before it is e&ecuted. ,his verification consists primarily of three types of checks5
 

.ranches are always to valid locations *ata is always initialiEed and references are always type9safe F



%ccess to private or package private data and methods is rigidly controlled.

,he first two of these checks take place primarily during the verification step that occurs when a class is loaded and made eligible for use. ,he third is primarily performed dynamically, when data items or methods of a class are first accessed by another class. ,he verifier permits only some bytecode sequences in valid programs, e.g. a jump (branch instruction can only target an instruction within the same method. -urthermore, the verifier ensures that any given instruction operates on a fi&ed stack location, allowing the 2#, compiler to transform stack accesses into fi&ed register accesses. .ecause of this, that the 2+' is a stack architecture does not imply a speed penalty for emulation on register9based architectures when using a 2#, compiler. #n the face of the code9verified 2+' architecture, it makes no difference to a 2#, compiler whether it gets named imaginary registers or imaginary stack positions that must be allocated to the target architecture:s registers. #n fact, code verification makes the 2+' different from a classic stack architecture which efficient emulation with a 2#, compiler is more complicated and typically carried out by a slower interpreter. Code verification also ensures that arbitrary bit patterns cannot get used as an address. 'emory protection is achieved without the need for a memory management unit (''G . ,hus, 2+' is an efficient way to get memory protection on simple architectures that lack an ''G. ,his is analogous to managed code in 'icrosoft:s .B4, Common Aanguage 7untime. ,he original specification for the bytecode verifier used natural language that was incomplete or incorrect in some respects. % number of attempts have been made to specify the 2+' as a formal system. .y doing this, the security of current 2+' implementations can more thoroughly be analyEed, and potential security e&ploits prevented. #t will also be possible to optimiEe the 2+' by skipping unnecessary safety checks, if the application being run is proved to be safe.

H

.onito%-based &on&u%%en&,he aim is binary compatibility. 4ach particular host operating system needs its own implementation of the 2+' and runtime. ,hese 2+'s interpret the bytecode semantically the same way, but the actual implementation may be different. 'ore comple& than just emulating bytecode is compatibly and efficiently implementing the 2ava core %"# that must be mapped to each host operating system.

I

Int%odu&tion to Ja(a Platfo%)s:%n edition of the 2ava platform is the name for a bundle of related programs from Cun that allow for developing and running programs written in the 2ava programming language. ,he platform is not specific to any one processor or operating system but rather an e&ecution engine (called a virtual machine and a compiler with a set of libraries that are implemented for various hardware and operating systems so that 2ava programs can run identically on all of them. ,he 2ava platform consists of several programs, each of which provides a distinct portion of its overall capabilities. -or e&ample, the 2ava compiler, which converts 2ava source code into 2ava bytecode (an intermediate language for the 2+' , is provided as part of the 2ava *evelopment Jit (2*J . ,he 2ava 7untime 4nvironment (274 , complementing the 2+' with a just in time (2#, compiler, converts intermediate bytecode into native machine code on the fly. %lso supplied are e&tensive libraries, precompiled in which are several other components, some available only in certain editions. ,he essential components in the platform are the 2ava language compiler, the libraries, and the runtime environment in which 2ava intermediate bytecode >e&ecutes> according to the rules laid out in the virtual machine specification.

Ja(a i%tual .a&hine/J .0:% 2ava virtual machine (2+' is a virtual machine capable of e&ecuting 2ava bytecode. #t is the code e&ecution component of the 2ava software platform. % 2ava virtual machine is software that is implemented on virtual and non9virtual hardware and on standard operating systems. % 2+' provides an environment in which 2ava bytecode can be e&ecuted, enabling such features as automated e&ception handling, which provides >root9cause> debugging information for every software error (e&ception , independent of the source code. % 2+' is distributed along with a set of standard class libraries that implement the 2ava application programming interface (%"# . %ppropriate %"#s bundled together with 2+' form the 2ava 7untime 4nvironment (274 .

?

2+'s are available for many hardware and software platforms. ,he use of the same bytecode for all 2+'s on all platforms allows 2ava to be described as a >write once, run anywhere> programming language, as opposed to >write once, compile anywhere>, which describes cross9platform compiled languages. ,hus, the 2+' is a crucial component of the 2ava platform. 2ava bytecode is an intermediate language which is typically compiled from 2ava, but it can also be compiled from other programming languages. -or e&ample, source code can be compiled to 2ava bytecode and e&ecuted on a 2+'. 0racle, the owner of 2ava, produces a 2+', but 2+'s using the >2ava> trademark may be developed by other companies as long as they adhere to the 2+' specification published by 0racle and to related contractual obligations. ,he heart of the 2ava platform is the concept of a >virtual machine> that e&ecutes 2ava bytecodes programs. ,his bytecode is the same no matter what hardware or operating system the program is running under. ,here is a 2#, compiler within the Java Virtual Machine, or 2+'. ,he 2#, compiler translates the 2ava bytecode into native processor instructions at run9time and caches the native code in memory during e&ecution. ,he use of bytecode as an intermediate language permits 2ava programs to run on any platform that has a virtual machine available. ,he use of a 2#, compiler means that 2ava applications, after a short delay during loading and once they have >warmed up> by being all or mostly 2#,9compiled, tend to run about as fast as native programs. Cince 274 version ).3, Cun:s 2+' implementation has included a just in time compiler instead of an interpreter. %lthough 2ava programs are cross platforms or platform independent, the code of the 2ava +irtual 'achines (2+' that e&ecute these programs is not. 4very supported operating platform has its own 2+'. % 2ava virtual machine (2+' , an implementation of the 2ava +irtual 'achine Cpecification, interprets compiled 2ava binary code (called bytecode for a computer:s processor (or >hardware platform> so that it can perform a 2ava

program:s instructions. 2ava was designed to allow application programs to be built that could be run on any platform without having to be rewritten or recompiled by the programmer for each separate platform. % 2ava virtual machine makes this possible @

because it is aware of the specific instruction lengths and other particularities of the platform. ,he 2ava +irtual 'achine Cpecification defines an abstract 99 rather than a real 99 machine or processor. ,he Cpecification specifies an instruction set, a set of registers, a stack, a >garbage heap,> and a method area. 0nce a 2ava virtual machine has been implemented for a given platform, any 2ava program (which, after compilation, is called bytecode can run on that platform. % 2ava virtual machine can either interpret the bytecode one instruction at a time (mapping it to a real processor instruction or the bytecode can be compiled further for the real processor using what is called a just9in9time compiler.

Ja(a Runti)e En(i%on)ent/JRE0:0racle:s 2ava e&ecution environment is termed the 2ava 7untime 4nvironment, or 274. "rograms intended to run on a 2+' must be compiled into a standardiEed portable binary format, which typically comes in the form of .class files. % program may consist of many classes in different files. -or easier distribution of large programs, multiple class files may be packaged together in a .jar file (short for 2ava archive . ,he 2ava application launcher, java, offers a standard way of e&ecuting 2ava code. Compare java. ,he 2+' runtime e&ecutes .class or .jar files, emulating the 2+' instruction

set by interpreting it, or using a just9in9time compiler (2#, such as 0racle:s =otspot. 2#, compiling, not interpreting, is used in most 2+'s today to achieve greater speed. ,here are also ahead9of9time compilers that enable developers to precompile class files into native code for particular platforms. Aike most virtual machines, the 2ava virtual machine has a stack9based architecture akin to a microcontroller/microprocessor. =owever, the 2+' also has low9level support for 2ava9like classes and methods, which amounts to a highly idiosyncratic memory model and capability9based architecture.

F

'**li&ation P%o,%a))in, Inte%fa&e:%n '**li&ation P%o,%a))in, Inte%fa&e ('PI is a source code9based specification intended to be used as an interface by software components to communicate with each other. %n %"# may include specifications for routines, data structures, object classes, and variables. %n %"# specification can take many forms, including an #nternational Ctandard such as "0C#K or vendor documentation such as the 'icrosoft ;indows %"#, or the libraries of a programming language, e.g. Ctandard ,emplate Aibrary in C<< or 2ava %"#. %n %"# can be5


Aanguage9dependent, meaning it is only available by using the synta& and elements of a particular language, which makes the %"# more convenient to use. Aanguage9independent, written so that it can be called from several programming languages. ,his is a desirable feature for a service9oriented %"# that is not bound to a specific process or system and may be provided as remote procedure calls or web services. -or e&ample, a website that allows users to review local restaurants is able to layer their reviews over maps taken from Doogle 'aps, because Doogle 'aps has an %"# that facilitates this functionality. Doogle 'aps: %"# controls what information a third9party site can use and how they can use it.



;e often have to rely on others to perform functions that you may not be able or permitted to do by yourself, such as opening a bank safety deposit bo&. Cimilarly, virtually all software has to request other software to do some things for it. ,o accomplish this, the asking program uses a set of standardiEed requests, called application programming interfaces (%"# , that have been defined for the program being called upon. %lmost every application depends on the %"#s of the underlying operating system to perform such basic functions as accessing the file system. #n essence, a program:s %"# defines the proper way for a developer to request services from that program. *evelopers can make requests by including calls in the code of their applications. ,he synta& is described in the documentation of the application being called. .y H

providing a means for requesting program services, an %"# is said to grant access to or open an application. .uilding an application with no %"#s is basically like building a house with no doors. ,he %"# for all computing purposes is how you open the blinds and the doors and e&change information.> %"#s also e&ist between applications. ;hen an industry settles on a data standard, a common %"# allowing access to applications that process that data often follows, ;alker says. 'iddleware works by providing a standardiEed, %"#9like interface that can allow applications on different platforms or written in different languages to interoperate. %lthough %"#s provide a quick and easy way to tap into an application, they can be constraining for certain power users such as independent software vendors, says %dam .raunstein, an analyst at 7obert -rances Droup #nc. in ;estport, Conn. 0pen source code e&poses every instruction and operation in an application and therefore offers the most fle&ibility. .ut understanding source code can be time9 consuming, and it also e&poses the author:s intellectual property. ;hen Bovell #nc. was rumored to be considering opening up the source code for its Bovell *irectory Cervices (B*C software last year, then9+ice "resident Chris Ctone said most corporate developers didn:t want to delve into open source code. #nstead, he said, they wanted additional sets of %"#s they could work with more quickly. Co far, Bovell has kept B*C code closed. Corporate developers should consider including %"#s in applications they develop, especially if they e&pect the applications to last and interact with other applications, .raunstein says. %s time goes on, the likelihood that another developer will need to tap an application:s services increases. =e says having the foresight to include %"#s saves subsequent developers from having to find and review the source code.

I

Inte,%ated De(elo*)ent En(i%on)ent:%n inte,%ated de(elo*)ent en(i%on)ent (IDE is a software application that provides comprehensive facilities to computer programmers for software development. %n #*4 normally consists of5
  

a source code editor build automation tools a debugger

%n integrated development environment (#*4 is a programming environment that has been packaged as an application program, typically consisting of a code editor, a compiler, a debugger, and a graphical user interface (DG# builder. ,he #*4 may be a standalone application or may be included as part of one or more e&isting and compatible applications. ,he .%C#C programming language, for e&ample, can be used within 'icrosoft 0ffice applications, which makes it possible to write a ;ord.asic program within the 'icrosoft ;ord application. #*4s provide a user9friendly framework for many modern programming languages, such as +isual .asic, 2ava, and "ower.uilder. #*4s for developing =,'A applications are among the most commonly used. -or e&ample, many people designing ;eb sites today use an #*4 (such as =omeCite, *reamweaver, or -ront"age for ;eb site development that automates many of the tasks involved. Come #*4s contain compiler, interpreter, or both, such as 'icrosoft +isual

Ctudio and 4clipseL others do not, such as Charp *evelop and AaEarus. ,he boundary between an integrated development environment and other parts of the broader software development environment is not well9defined. Cometimes a version control system and various tools are integrated to simplify the construction of a DG#. 'any modern #*4s also have a class browser, an object inspector, and a class hierarchy diagram, for use with object9oriented software development.

M

#*4s are designed to ma&imiEe programmer productivity by providing tightly9knit components with similar user interfaces. ,his should mean that the programmer has to do less mode switching versus using discrete development programs. =owever, because an #*4 is a complicated piece of software by its very nature, this higher productivity only occurs after a lengthy learning process. ,ypically an #*4 is dedicated to a specific programming language, allowing a feature set that most closely matches the programming paradigms of the language. =owever, there are some multiple9language #*4s, such as 4clipse, %ctive Ctate Jomodo, #ntelli2 #*4%, 0racle 2*eveloper, recent versions of Bet.eans, 'icrosoft +isual Ctudio, Denuitec 'y4clipse, ;in*ev, and Kcode.

#*4s typically present a single program in which all development is done. ,his program typically provides many features for authoring, modifying, compiling, deploying and debugging software. ,he aim is to abstract the configuration necessary to piece together command line utilities in a cohesive unit, which theoretically reduces the time to learn a language, and increases developer productivity. #t is also thought that the tight integration of development tasks can further increase productivity. -or e&ample, code can be parsed while being written, providing instant feedback on synta& errors. ;hile most modern #*4s are graphical, #*4s in use before the advent of windowing systems (such as 'icrosoft ;indows or K ;indow Cystem (K)) were te&t9based, using function keys or hotkeys to perform various tasks (,urbo "ascal is a common e&ample . ,his contrasts with software development using unrelated tools, such as vi, DCC or make. % free, open9source #ntegrated *evelopment 4nvironment for software developers. %ll the tools needed to create professional desktop, enterprise, web, and mobile applications with the 2ava platform, as well as with C/C<<, "=", 2avaCcript and Droovy. NetBeans IDE 123 introduces support for 2ava -K 3.N, as well as tools for visual debugging of Cwing and 2ava-K user interfaces. %dditional highlights include Dit support integrated into the #*4, new "=" debugging features, various 2ava 44 and 'aven improvements, and more. Bet.eans refers to both a platform framework for 2ava desktop applications, and an integrated development environment (#*4 for developing with 2ava, 2avaCcript, "=", "ython (no longer supported after Bet.eans H , Droovy, C, C< )N

<, Ccala , Clojure, and others. ,he Bet.eans #*4 H.N no longer supports 7uby and 7uby on 7ails, but a third party has begun work on a separate plug9in. ,he Bet.eans #*4 is written in 2ava and can run on ;indows, 'ac 0C, Ainu&, Colaris and other platforms supporting a compatible 2+'. % pre9e&isting 2+' or a 2*J is not required.,he Bet.eans platform allows applications to be developed from a set of modular software components called modules. %pplications based on the Bet.eans platform (including the Bet.eans #*4 can be e&tended by third party developers. ,he Bet.eans "latform features a very powerful Windo4 .ana,e)ent S-ste), letting you declaratively define default window positions, resiEing and do&5in,6undo&5in, windows, )ini)i7e6)a8i)i7e9 *e%sist 4indo4 state, group behavior, etc. e%sion 123 introduces a couple of new features here. !ou can see them in the #*4 and reuse them in your Bet.eans "latform applications. ,he most important enhancement seems to be >Pe%s*e&ti(es>, which are named >Roles> here as a way of switching between 4indo4 la-outs. ;hen registering a window you can now add one or more roles to it in the %nnotation. 0ne e&tremely useful new feature is the new ;indow Aayout *esigner allowing you to create new Aayouts via drag and drop. !ou can invoke this functionality using the new >"a-out of Windo4s: 4i7a%d. ,he ;iEard will launch your application in a special mode, and allow you to create or change ;indow "ositions, aka >'odes> and save the changes to a layer file and the files required for defining new 'odes.

St%uts:,he %pache Ctruts web framework is a free open9source solution for creating 2ava web applications.;eb applications differ from conventional websites in that web applications can create a dynamic response. 'any websites deliver only static pages. % web application can interact with databases and business logic engines to customiEe a response.

))

;eb applications based on 2ava Cerver "ages sometimes commingle database code, page design code, and control flow code. #n practice, we find that unless these concerns are separated, larger applications become difficult to maintain. 0ne way to separate concerns in a software application is to use a 'odel9+iew9 Controller ('+C architecture. ,he Model represents the business or database code, the View represents the page design code, and the Controller represents the navigational code. ,he Ctruts framework is designed to help developers create web applications that utiliEe '+C architecture. ,he framework provides three key components5
•

% >request> handler provided by the application developer that is mapped to a standard G7#. % >response> handler that transfers control to another resource which completes the response. % tag library that helps developers create interactive form9based applications with server pages.

•

•

,he framework:s architecture and tags are buEEword compliant. Ctruts works well with conventional 74C, applications and with nouveau technologies like C0%" and %2%K. ,he %pache Ctruts "roject is the open source community that creates and maintains the %pache Ctruts framework. ,he project consists of a diverse group of volunteers who share common values regarding collaborative, community9based open source development. ,he %pache Ctruts "roject is proud to share these values with our parent organiEation5 ,he %pache Coftware -oundation. ,he project is called >Ctruts> because the framework is meant to furnish the >invisible underpinnings> that support professional application development. Ctruts provides the glue that joins the various elements of the standard 2ava platform into a coherent whole. 0ur goal is to leverage e&isting standards by producing the missing pieces we need to create enterprise9grade applications that are easy to maintain over time. ,he %pache Ctruts "roject offers two major versions of the Ctruts framework. Ctruts ) is recogniEed as the most popular web application framework for 2ava. ,he ).& framework )3

is mature, well9documented, and widely supported. Ctruts ) is the best choice for teams who value proven solutions to common problems. % strut 3 was originally known as ;eb;ork 3. %fter working independently for several years, the ;eb;ork and Ctruts communities joined forces to create Ctruts 3. ,he 3.& framework is the best choice for teams who value elegant solutions to difficult problems.

St%uts *%os:•

Use of JSP ta, )e&hanis) ,he tag feature promotes reusable code and abstracts 2ava code from the 2C" file. ,his feature allows nice integration into 2C"9based development tools that allow authoring with tags.

•

Ta, lib%a%;hy re9invent the wheel, or a tag libraryO #f you cannot find something you need in the library, contribute. #n addition, Ctruts provides a starting point if you are learning 2C" tag technology.

•

O*en sou%&e !ou have all the advantages of open source, such as being able to see the code and having everyone else using the library reviewing the code. 'any eyes make for great code review.

•

Sa)*le . C i)*le)entation Ctruts offers some insight if you want to create your own '+C implementation.

•

.ana,e the *%oble) s*a&e *ivide and conquer is a nice way of solving the problem and making the problem

)8

Int%odu&tion to J;EE: ,he multi9tier architecture such as C0.7% has got its own advantages in terms of scalability, performance and reliability. #n a multi9tier architecture, a client does not interact directly with the server. #nstead, it first contacts another layer called 'iddleware. ,he middleware instantiates the server applications and messages the server object. #t returns results to the clients. ,he presence of a middleware layer allows programmers to concentrate on business logic of application. ,he middleware handles low9lever services, such as thread handling, security, and transactions management. Cun 'icrosystems introduced the 2344 application server and the enterprise 2ava .ean (42. specifications as a venture into the multi9tier component architecture. 2344 functions as a middle tier server in three tier architectures. #t provides certain specifications that can be used to implement enterprise solutions for certain all types of business requirements. 2344 also offers cost effective solution for business solution. 2344 is used for developing, deploying and e&ecuting applications in a distributed environment. ,he 2344 applications server acts as a platform for implementing various server side technologies Cervlets, 2ava Cerver "ages (2C" and 4nterprise 2ava .ean (42. . 2344 allows you to focus on your business logic program. ,he business logic is coded in java program, which are reusable component that can be accessed client program 42. runs on 2344 server. #n 2344 security is handled almost entirely by platform and its admin. ,he developer does not have to worry about writing the security logic.

•

J;EE '**li&ation:

2344 applications are comple& access data from a variety of source and cater to a variety of client. ,o manage these applications the business function conducted in the middle )?

tier. ,he 2344 platform acts as a middle tier and provides the necessary environment needed by the application. ,he 2344 building multi9tier application. ,o create a 2344 application we need to create following three components5 /30 J;EE a**li&ation &lient /;0 Ente%*%ise Bean /<0 Web &o)*onent 4ach of these components is packaged into a file with a specified file format. % 2344 application client is a 2ava application that run in a environment that enable it to access to the 2344 services. % 2344 application client is packaged into a .jar (2ava archive file. ,he web components are packaged into a .war (;eb archive file. %n 4nterprise .ean consists of three files5 the 42. class, =ome and 7emote #nterfaces. ,he 4nterprise .eans are bundled into an 42..jar file. ,he .jar, .war and 42..jar are assembled into a 2344 application, which is an .ear file. ,he .ear file is then deployed to the 2344 server. ,he race for market share in the database industry has increased with the advent of client9 server platforms. 0racle is one of the most successful companies that has released a number of development tools including CPA Q"AGC, "A/CPA that enables faster and easier application development and its management. platform provides1 write once, run anywhere1, portability and scalability for multi9tier application. #t also minimiEes comple&ity for

0racle is the robust *atabase Cystem, it support very large database. 'oreover 0racle is widely used as back end for client / server applications. %dministrative tools of 0racle help in securing the *ata / #nformation.

)@

P%o&ess of &%eatin, a J;EE a**li&ation:

4nterprise .ean (.jar file

Component (.jar file

%ssembled 2344 %pplication Cerver (.jar file *eployed

2344 Cerver

)F

JDBC ,here are many classifications of databases available as =ierarchical database, Betwork database, 7elational database, 0bject databases and soon. *ue their fle&ibility 7elational database management systems are most successful bread of databases in the history of computing. 4&5 9 0racle, #.'db3, and 'icrosoft CPA Cerver. % technology that enables 2C" base applications to interact directly with database engines is called 2ava *atabase Connectivity and is an integral part of 2ava platform. 2*.C/2C" based web application access the database connections. ,hese connections must be managed carefully by the application especially if a large number of concurrent users may be accessing them. ,o make this performance optimiEation 2*.C uses a mechanism called connection pooling. ,he evaluation of this open database access technology has led to a 'irada of driver architecture.

)H

Inte%a&tion of JSP Pa,e 4ith JDBC %pplication Cerver 'achine Client 'achine B%o4se% 4ith !T."
JSP JDBC Web

server

4ngine

*river

*. Cerver 'achine RDBMS Server

=ere the browser using the web application is not required to support java at all. ,he 2C" has full control over how many 2*.C connections are made to the server. ,he client never makes direct 2*.C connection to the server. ,his solution can work readily through a firewall, only standard =,," is used between the web server and the client.

%s a bonus this solution sends itself to easily secured information simply by adding secured socket layer support to the web server. .ecause of this separation of the presentation from the business logic, which is separated from the database logic, this sort )I

of system is often called three tiers of the system. %lthough the application server and database server can also running on the same server machine. ,here is still one minor problem with this scenario. "roject personal accessing the 2C" page containing the embedded 2*.C code can easily and inadvertently modify the database access code and this may result in an erroneous application or even corrupted database. ,here are 3 solutions for this5 ). Create java beans or java classes that encapsulate all the 2*.C operations. ,his is significantly better solution. .ut instantiation, initialiEation and parameteriEation of the java class or the beans can still represent a significant amount of embedded java code with in the 2C". 3. Create a tag e&tension set to Rpushdown$ all the database access logic. ,he data access logic programmers write the set of custom tags. ,he 2C" application logic designers will then use the set of custom tag to create their application.

JSP En,ine

2C"$s

Custom tag e&tension

Custom 2ava beans/classes

2*.C *river

0ther *. access ,echnologies

)M

B'C=-END
.S '&&ess 'icrosoft 0ffice %ccess, previously known as 'icrosoft %ccess, is a relational database management system from 'icrosoft that combines the relational 'icrosoft 2et *atabase 4ngine with a graphical user interface and software9development tools. #t is a member of the 'icrosoft 0ffice suite of applications, included in the "rofessional and higher editions or sold separately. #n mid9'ay 3N)N, the current version of 'icrosoft %ccess 3N)N was released by 'icrosoft in 0ffice 3N)NL 'icrosoft 0ffice %ccess 3NNH was the prior version. %ccess stores data in its own format based on the %ccess 2et *atabase 4ngine. #t can also import or link directly to data stored in other applications and databases

3N

RE>UIRE.ENTS 'N'"$S$S
S$STE. STUD$ 'ND PROB"E. ?OR.U"'TION T!E E@ISTIN# S$STE. ,he e&isting system i.e, classifieds and yellow pages system works by manually supplying information regarding an %dvertisement to be placed in the media (say Bewspapers, magaEines etc. which must be checked thoroughly before given for final print.. ,he e&isting system has got lot of intricacies within itself and need lot of human effort and paper works. %ll above the data need to be maintained properly and maintaining this is a tedious and risky process as a small printing error may completely change the sense of the %dvertisement. 'oreover to view a data or to keep a record of a particular %dvertisement may need lot of paper to be searched.

Come of the negative aspects of the e&isting system are as follows5 ) 3 Course of action is time consuming. ;herever a need for search arises, the process evolves search through paper records. 7eadability of records is constrained. %ll the records may not be handled or written by the same person. Co the format and style of records differ and hence it is difficult to understand. 8 ? @ "aper records are easily damaged in course of time. ,he life time of paper record is unreliable less that it easily gets spoiled. 4&penditure is high. 'anual system needs added man power. #t is difficult for the user to categoriEe and do the comparative study of the %*$s on the basis of just reading about it on a piece of "aper. ,o overcome these, the proposed system has been suggested.

3)

T!E PROPOSED S$STE. ,he proposed system is a computeriEed one. ,his has greater accuracy and efficiency. ,his takes only limited time for retrieval of desired result from the user. ,he proposed system can be used to maintain efficiently the postings and retrieval of any type of %dvertisement posted by a "oster. ,he proposed system is also useful and helpful in checking out different %dvertisements by a +iewer so that he/she can easily categoriEe and select the appropriate %* for him/herself depending on the requirement and his/her choice. =e/she can also create his/her mail account using my system. Cince my system is allowing .anner %dvertisements to obtain revenue out of it, a user can post his/her company$s or firm$s %dvertisement using my system. ,he system includes two users5 ) 3 %dministrator "oster ( post %*$s Deneral Gser +iewer ( view %*$s ,he user gets into the system using user name and a unique password. 4ach user has his own accessibility permission to accomplish his task flawlessly. ,he administrator also has a #* and password to get access to the system so that no unauthoriEed person is able to keep an eye on the working of the complete system. %dvantages of the proposed system are ) 3 8 ? 4asy access to the data ,he new system is more user friendly, reliable and fle&ible. "op9up menus to carry out transactions for a new user, and for other alert messages. ,imely 7eport generation.

ClassifiedsOnline (online classified ( yellow pages is being made as web9 application. 33

"roject can be categoriEed in two ways59 • • "o&al '%ea Net4o%5 *%o+e&ts2

Dist%ibuted P%o+e&ts. Aocal %rea Betwork projects are those projects where application has to be

incorporated in the Aocal area network of the client i.e within its premises only. #n case of A%B, server is not remotely located and client accesses the application through the network. =ere the question of platform independence does not arise and we can use the technologies like5 +isual .asic, -o& pro, *3k or C, C<<, etc. *istributed projects are those projects where application is remotely situated. #n these kinds of projects, application is remotely situated on to the remote server from where client machine accesses the application. ;%B and #nternet is a kind of distributed application where client machine connects to the remote server and application is downloaded on to the client machine. =ere the question of platform independence arises and we use technologies like 2ava Cervlet, 2ava Cerver "ages, 2ava .eans, 7'#, etc.

38

Data ?lo4 Dia,%a)s
*ata flow diagrams represent the flow of data through a system. % *-* is composed of5 ). *ata movement shown by tagged arrows. 3. ,ransformation or process of data shown by named bubbles. 8. Cources and destination of data represented by named rectangles. ?. Ctatic storage or data at rest denoted by an open rectangle that is named. % data flow diagram (*-* is a graphical representation of the >flow> of data through an information system, modelling its process aspects. 0ften they are a preliminary step used to create an overview of the system which can later be elaborated. *-*s can also be used for the visualiEation of data processing (structured design .

% *-* shows what kinds of data will be input to and output from the system, where the data will come from and go to, and where the data will be stored. #t does not show information about the timing of processes, or information about whether processes will operate in sequence or in parallel.

+arious Cymbols used in *-* are59

3?

Conte8t "e(el D?D fo% ClassifiedsOnline

IEWER

Cearch Contacts +iew Contacts Cearch %ds +iew %ds

7egistration Aogin

POSTER

ClassifiedsOnlin
e

"ost a new %d. 4dit ( 'aintain ads +iew 7esponses

Cend 7esponse

/ Online &lassifieds A $ello4 Pa,es 0

'aintain Category

'D.INISTR'TOR

+iew 7egd. Gsers

Chow .anner %ds
3@

D'T'B'SE DESI#N
D'T' STRUCTURES: ,his part of the *esign consists the overall database schema or we can say that tables which consists various types of records. ,able of aa database consists attributes, entities, tuples for storing and manipulating records Come of the tables are as follows5

•

'D: ,his table maintains details of the different %dvertisements.

•

C'TE#OR$: ,his table maintains details of the different categories listed by the %dministrator.

3F

•

.E.BERS: ,his table maintains details of the members of the system including admin.

3H

CODIN#
,his means program construction with procedural specifications has finished and the coding for the program begins5

• • •

0nce the design phase was over, coding commenced

Coding is natural consequence of design.

Coding step translate a detailed design representation of software into a programming language realiEation.

•

'ain emphasis while coding was on style so that the end result was an optimiEed code.

,he following points were kept into consideration while coding5

Codin, St-le :-

,he structured programming method was used in all the modules the project. #t incorporated the following features

• •

,he code has been written so that the definition and implementation of each function is contained in one file. % group of related function was clubbed together in one file to include it when needed and save us from the labour of writing it again and again.

Na)in, Con(ention:3I

•

%s the project siEe grows, so does the comple&ity of recogniEing the purpose of the variables. ,hus the variables were given meaningful names, which would help in understanding the conte&t and the purpose of the variable.

•

,he function names are also given meaningful names that can be easily understood by the user.

Indentation:2udicious use of indentation can make the task of reading and understanding a program much simpler. #ndentation is an essential part of a goog program. #f code id intended without thought itv will seriously affect the readability of the program.

•

,he higher9level statements like he definition of the variables, constants and the function are intended, with each nested block intended, stating their purpose in the code.

•

.lank line is also left between each function definition to make the code look neat.

•

#ndentation for each source file stating he purpose of the file is also done.

3M

TESTIN#

Gnit testing

'odule testing

Cub9system testing

Cystem testing %cceptance testing

Unit Testin, :Gnit testing focuses verification effort on the smallest unit of software i.e. the module. Gsing the detailed design and the process specifications, testing is done to uncover errors within the boundary of the module. %ll modules must be successful in the unit test before the start of the integration testing begins. #n this project each service can be thought of a module. ,here are so many modules like Aogin, =7 *epartment, #nterviewer Cection, etc. 4ach module has been tested by giving different sets of inputs. ;hen developing the module as well as finishing the development, the module works without any error. ,he inputs are validated when accepting them from the user. Inte,%ation Testin, :8N

%fter unit testing, we have to perform integration testing. ,he goal here is to see if modules can be integrated properly, the emphasis being on testing interfaces between modules. ,his testing activity can be considered as testing the design and hence the emphasis on testing module interactions. #n this project the main system is formed by integrating all the modules. ;hen integrating all the modules # have checked whether the integration effects working of any of the services by giving different combinations of inputs with which the two services run perfectly before #ntegration.

S-ste) Testin, :-

=ere the Cystem testing involved is the most widely used testing process consisting of five stages as shown in the figure. #n general, the sequence of testing activities is component testing, integration testing, and then user testing. =owever, as defects are discovered at any one stage, they require program modifications to correct them and this may require other stages in the testing process to be repeated.

,esting is the process of detecting errors. ,esting performs a very critical role for quality assurance and for ensuring the reliability of the software. ,he results of testing are used later on during maintenance also. ,esting is vital to the success of the system. Cystem testing makes a logical assumption that if the parts of the system are correct, the goal will be successfully achieved. #n adequate testing or non9testing leads to errors that may not appear until months or even years later (7emember the Bew !ork three day power failure due to a misplaced R.reak$ statement . ,his creates two problems5 ). ,he time lag between the cause and the appearance of the problem. 8)

3.

,he time interval effect of the system errors on files and the records on the system.

% small error can conceivably e&plode into a much larger problem. 4ffective testing early in the process translates directly into long term cost savings from a reduced number of errors. %nother reason for system testing is it$s utility as a user oriented vehicle before implementation. ,he best program is worthless if it does not meet the user requirements. Gnfortunately, the user$s demands are often compromised by efforts to facilitate program or design efficiency in terms of processing time or design efficiency. ,hus in this phase we went to test the code we wrote. ;e needed to know if the code compiled with the design or notO ;hether the code gave the desired outputs on given inputsO ;hether it was ready to be installed on the user$s computer or some more modifications were neededO

'&&e*tan&e Testin, :%cceptance ,esting is performed with realistic data of the client to demonstrate that the software is working satisfactorily. ,esting here is focused on e&ternal behavior of the systemL the internal logic of program is not emphasiEed. ,est cases should be selected so that the largest number of attributes of an equivalence class is e&ercised at once. ,he testing phase is an important part of software development. #t is the process of finding errors and missing operations and also a complete verification to determine whether the objectives are met and the user requirements are satisfied. White Bo8 Testin, :,his is a unit testing method, where a unit will be taken at a time and tested thoroughly at a statement level to find the ma&imum possible errors. 83

# tested step wise every piece of code, taking care that every statement in the code is e&ecuted at least once. ,he white bo& testing is also called Dlass .o& ,esting. # have generated a list of test cases, sample data, which is used to check all possible combinations of e&ecution paths through the code at every module level. ;hite9bo& test focuses on the program control structure. ,est cases are derived to ensure that all statement in the program control structure. ,est cases are derived to ensure that all statement in the program control structure. ,est cases are derived to ensure that all statement in the program has been e&ecuted at least once during testing and that all logical conditions have been e&ercised. .asis path testing, a white bo& technique, makes use of program graphs (or graph matrices to derive the set of linearly independent test that will ensure coverage. Condition and data flow testing further e&ercising degrees of comple&ity. Bla&5 Bo8 Testin, :,his testing method considers a module as a single unit and checks the unit at interface and communication with other modules rather getting into details at statement level. =ere the module will be treated as a block that will take some input and generate output. 0utput for a given set of input combinations are forwarded to other modules. .lack9bo& test are designed to uncover errors functional requirement without regard to the internal workings of a program. .lack9bo& testing techniques focus on the information domain of the software, deriving test cases by partitioning the input and output domain of a program in manner that provides through test coverage. ,he black9 bo& test is used to demonstrate that software functions are operational, that input is properly produced, and that the integrity of e&ternal information are maintained. % black9 bo& test e&amines some fundamental aspect of a system with little or no regard for the integral logical structure of the software.

88

I.P"E.ENT'TION
Int%odu&tion Cystem implementation is the stage when the user has thoroughly tested the system and approves all the features provided by the system. ,he various tests are performed and the system is approved only after all the requirements are met and the user is satisfied. ,he new system may be totally new, replacing an e&isting manual or automated system, or it may be a major modification to an e&isting system. #n either case, proper implementation is essential to provide a reliable system to meet organiEational requirements. Cuccessful implementation may not guarantee improvement in the organiEation using the new system (that is a design question , but improper will prevent it. #mplementation is the process of having systems personnel check out and put new equipment into use, train users, install the new application and construct any files of data needed to use it. ,his phase is less creative than system design. *epending on the siEe of the organiEation that will be involved in using the application and the risk involved in its use, systems developers may choose to test the operation in only one area of the firm with only one or two persons. Cometimes, they will run both old and new system in parallel way to com9pare the results. #n still other situations, system developers stop using the old system one day and start using the new one the ne&t. ,he implementation of the web based or lan based networked project has some e&tra steps at the time of implementation. ;e need to configure the system according the requirement of the software. -or the project we need to install and configure ;eblogic server I.) , database server, and the deployment directory for the project.

8?

's*e&ts of I)*le)entation ,he two aspects of implementation are5 • • ,raining "ersonnel Conversion "rocedures

TR'ININ# 4ven well designed and technically elegant systems can succeed or fail because of the way they are used. ,herefore the quality of the training received by the personnel involved with the system in various ways helps or hinders, and may even prevent, the successful implementation of an information system. Cince, =uman 7esource 7ecruitment "rocess is web9based and user friendly, not much effort was required in training process.

CON ERSION: Conversion is the process of changing from the old system to the new system. ,here are two methods of handling systems conversion5 • • "arallel 7un #mmediate cut9off

8@

•

Pa%allel Run

#n this approach, the old system and the new system are used simultaneously for some period of time so that the performance of the new system can be monitored and compared with that of the old system. %lso in case of failure of the new system, the user can fall back on the old system. ,he risk of this approach is that the user may never want to shift to new system.

•

I))ediate &ut-off

#n this method, the use of the old system ceases as soon as the new system is implemented and bought in to palace. ,he old system becomes redundant from the day of implementation of the new system. ,here is the high risk involved in this approach if the new system is not tested rigorously. ,his is because of the fact that if the new system fails, then there will not be anything to fall back upon. ,he advantage of this approach is that both the systems need not be used simultaneously.

I)*le)entation Tools ,he project was implemented using 2ava server pages,=,'A,2ava beans.,he implementation work was carried out in ;indows K"/3NNN server platform.

) 3 8

2344 ;eblogic I.) 0racle Ii

8F

.'INTEN'NCE
'aintenance or enhancement can be classified as5 9 • • • Co%%e&ti(e 'da*ti(e Pe%fe&ti(e2 •

Co%%e&ti(e .aintenan&e means repairing processing or performance failures or making changes because of previously uncorrected problems or false assumptions.

•

'da*ti(e .aintenan&e means changing the program function.

•

Pe%fe&ti(e .aintenan&e means enhancing the performance or modifying the program(s to respond to the user$s additional or changing needs.

'aintenance is actually the implementation of the post implementation review plan. %s important as it is, many programmers and analysts are reluctant to perform or identify themselves with the maintenance effort. ,here are psychological, personality and professional reasons for this. #n any case, a first class effort must be made to ensure that software changes are made properly and in time to keep the system in tune with user specifications.

'aintenance is costly. 0ne way to reduce maintenance costs is through maintenance management and software modification audits. Coftware modification consists of program rewrites system level updates, and re9audits of low ranking programs to verify and correct the soft spots. ,he outcome should be more reliable software, a reduced maintenance backlog, and higher satisfaction and morale among 8H

the maintenance staff. #n =77", care has been taken towards maintenanceL Aoop =oles can be eradicated from the system from time to time according to changing requirements with lesser cost.

8I

S&%een Shots
!O.E P'#E

"O#IN P'#E

8M

RE#ISTER NEW .E.BER

'DD NEW 'D

ie4 'DS ?N

IEW C'TE#ORIES

INSERT INTO C'TE#OR$

?)

EDIT C'TE#ORIES

IEW 'D ?3

?8

?UTURE SCOPE

 "roviding the C'C alerts facility to users to remove the dependency on email account (web .  "roviding the social media site to e&press, review and share in the form of .logs, "hotos, +ideos, discussions in multiple e&plosively popular areas of interest such as 'ovies, ,ravel , events and much more.  Burturing the dream of providing 4mail account facility to users so they can feel the independence of mail account at the same site. ,he idea of having a 'ail account has been dealt in the system but 'any more functionalities can be added to it.

??

DEPENDENCIES
 #t doesn$t matter how efficiently the application works, if the bandwidth is not sufficient the transaction will take more time then e&pected.  0racle and 0racle 2*.C90*.C drivers for connectivity.  2ava ;eb server is required for the application.  %lthough this software is architecturally independent but following hardware resources are required. -or i.e. any #.' compatible "C or any other workstation with mouse support and relevant software.

?@

"I.IT'TIONS
Cince, every system has some limitations so our proposed system is also not untouchable in this regard. %lthough it includes every kind of features, but it can$t be used in a huge organiEation where number of networks are very large, because the database used in this system is an average one. %lso it doesn$t have different kind of access feature for different users. ,hough it was planned for this system to be absolutely perfect but everything as such has some limitations, so does the Cystem. -ollowing may be the drawback in this system. • ,hough this system is developed as a multi user system but it is not a real time system. • ,he interaction with the database, every time they are loaded thus the system tends to be a bit slow. • Bo direct access to Customers

?F

CONC"USIONS
%s evidence of the success of this mission, there are millions of items listed each day in thousands of different categories. ,here are items for almost any interest that one could imagine, from sheet music to automobiles to hand tools to real estate. %nd the variety doesn$t stop there. Beed a computerO 0ne may find it listed in the proper category, in any configuration from very old and obsolete to the latest greatest machine available. ;hat about antiquesO 0ne can find an antique quilt that is up for highest bid, or maybe an old violin, whose beautiful tones have enchanted many though its years. ,ickets. 'aybe a ticket to the ne&t concert of ones favorite artist or play production. 0ne can even find that special bottle of wine, some aged, e&otic cheese, and the perfect Rmood$ music for that special occasion. #n this instance it may be true that on e.ay, they have something for everybody, whatever their tastes may be.

?H

BIBI"IO#R'P!$
BOO=S 9 2ava93 Complete 7eference 9 2ava Cervlet "rogramming 9 "ure 2avaCcript 9 =,'A complete 9 2ava Cerver "rogramming 9 by "atrick Baughton 9 by 0:7eilly 9 by 2ason Dilliam, Charlton ,ry, 7.%llen ;yke 9 .". publications. 9 by %press publication.

RE?ERENCES
• • • • • • • http5//www.sun.com http5//www.coreservlets.com http5//www.serverside.com http5//www.w8schools.com http5//www.google.com http5//www.webopedia.com http5//www.ddj.com

?I