Secrets of software success,novel secret of nagas jewellery,book of secrets 3 - PDF Review

21.08.2014
This chapter identifies twelve key characteristics of software development that makes it unique. When we try to find out what's different about software and software development, the first question that comes to mind is "Different from what?" So let's compare software development to road building.
The following sections introduce 12 distinct but interrelated differences between software development and other common business endeavors (see Figure 2-1). You might expect that a 100,000-line program would be ten times more complex than a 10,000-line program. Skilled developers endeavor to reduce this overall level of complexity by isolating various parts of a system from each other. Despite such techniques, developers still find that the complexity of their software increases faster than its size. Computer programs are the most intricate, delicately balanced, and finely interwoven of all the products of human industry to date.
Software is a codification of a huge set of behaviors: if this occurs, then that should happen, and so on. The same things that make it hard to visualize software make it hard to draw blueprints of that software.
Software, on the other hand, is just a codification of the behaviors that the programmers and users want to take place. Even encapsulation, which can reduce the overall complexity of a system, doesn't release us from the burden of having to individually define each and every one of these instructions (or behaviors); it just helps us to organize them better.
A map or a blueprint for a piece of software must greatly simplify the representation in order to be comprehensible. Software is normally commissioned for the needs of users and managers, not professional developers. Moreover, as we saw in the previous section, it is impossible to accurately blueprint software, or draw up a complete set of requirements before the software has been completed in some form or another. To be successful, users and developers must work together to refine the requirements for the software.
All of this suggests that the belief that you have, or ever can have, a comprehensive and finalized set of requirements is a self-deception.
In contrast, drawing up the specifications for a new road is a relatively straightforward process: only the route, number of lanes, intersections, surfacing, and so on need to be defined.
Note: It is uniquely difficult to define a complete set of requirements for software before beginning development. Twenty years ago, we were struggling with the MS-DOS operating system and creating simple spreadsheets on our PCs. A framework is a toolkit, just like a Lego set, that you can use to build a variety of items. Given that some of the most important government and business software is now being built with these enterprise application frameworks, you might expect that they have a long and distinguished history, and that they'd be stable and mature products. In contrast, we've been building roads for thousands of years, ever since the time of the ancient Roman and Chinese civilizations.
Note: Software development technologies change faster than other construction technologies.
Extensibility is the ability to add functionality or modify existing functionality without impacting existing system functionality. Most programmers have had the painful experience of trying to modify a system that works well, but in which it's virtually impossible to make changes without breaking some of its functionality. Code becomes fragile when it's put together in an ad hoc fashion, without sufficient attention being paid to its architecture. One of these problems was a poor design practice, which became so prevalent that it ended up with a name of its own: the Magic Pushbutton. In the Magic Pushbutton, the only event handler that does any real work is the one that's called when the user clicks the OK button. Over time, every field of human endeavor develops best practices to counter common mistakes like this.
The enterprise application frameworks we've discussed have been around for only a fraction of that time.
Note: Most software development technologies are not mature enough to have a set of proven best practices.
However challenging it is to develop software using an enterprise application framework, it's still much simpler and quicker than attempting to create your own versions of these tools from scratch. Until recently, these software components were distributed on CD-ROMs, and copied into any application that required them.
Enterprise application frameworks contain a wealth of functionality, and beyond that there is even more functionality available from third-party software components. Note: Software development has far more technologies, and its technologies have far more complexity than a single individual can hope to gain expertise with. For example, Microsoft's BizTalk Server 2004 is a very different product from BizTalk Server 2000. Moreover, developers work with an enormous range of specialized third-party software components.
Whatever a developer was working on even three to four years ago is unlikely to be of any direct use today.
It's true that long lists of desired technology skills, which are so prevalent in IT job advertisements, are virtually useless. Note: Expertise with particular software development technologies is very quickly outdated, and therefore most specific skills are learned on the job. As noted in previous points, the requirements for a piece of software will invariably be incomplete. This means that the development process is a process of discovery—progressively finding out the exact character of the software that will meet the customer's needs. The project will probably include software tools and components that are new or unfamiliar to the developers. Recently, however, some software publishers have begun selling beta releases to their customers.
We can't take it for granted that a given software tool or component will work as we expect it to, or do everything that we need when we use it to create our software. So software development is also a process of discovering whether and how the chosen technology can be made to perform the role that's required of it.
Automation is the automatic operation and control of a piece of equipment, or of an entire system. In some industries, manufacturing is done in factories that are empty of workers except for a few maintenance staff, and production has been completely automated. No matter how much labor is saved through the use of machinery in road making, road workers must still do a substantial amount of repetitive work. All of the repetitive work can be automated in software development, and that's because software doesn't exist in the real world.
Common tasks and services are included in enterprise application frameworks, and more specialized ones can be done by third-party software components, so programmers work more efficiently because much of their work has already been done for them. Note: Software development has been automated to a greater degree than other project-based activities. In contrast, software development is a process of research, so at no point can definitive plans be drawn up. If tasks can't be well defined, then we can't cleanly separate the design and construction phases. When developers create a new feature in a piece of software, their task is simply to answer the question "exactly how is this feature going to work?" They will add a set of instructions to the source code that defines in every detail how the feature will work.
Note: Unlike other products, software is not constructed, but rather designed into existence. Last-minute changes to requirements are rare in road building because the consequences are so severe.
It's true that substantial changes can often be made quickly and easily, but to properly implement them you really have to revise the architecture of the software so that it gracefully supports the new functionality; otherwise you'll just create a mess and make the software more fragile. In addition to designing the architecture, we must also design our development process to support change. Note: Software can be modified rapidly, and this pace is expected, but it's better to implement the changes properly. Moreover, clients see how easily changes can be made, and expect that they can change their minds at any point.
Change is inevitable, and if a piece of software isn't built to support change then it will fall apart even as it is being built. It's easy to see the problems that change can bring to a project, and begin to see change as the "enemy," but is attempting to eliminate all change a viable option? In this chapter, we've taken a whirlwind tour of the software development landscape to set the scene for the rest of the book.
Software development isn't just a process of creating software; it's also a process of learning how to create the software that is best suited for its purpose.
No software is perfect as first envisioned; it will always require changes to make it best suit its role. This article has no explicit license attached to it but may contain usage terms in the article text or the download files themselves.
We love to provide educational content for a variety of organizations, including sessions we sponsor. In addition to providing the best pricing we have, as a Premier Intuit Reseller, we are able to match pricing you find anywhere else. TIP: Double window envelopes help improve efficiency by eliminating the need to address envelopes when paying bills. The Payroll Liability Report is useful in documenting the payroll liabilities due and payable.  This amount should agree with the pay payroll liabilities screen and the general ledger detail for the liability account. TIP: This report in version 2004 is now set up with the default by columns, in previous versions to create a similar report, change the columns to month from total only. TIP: This report also shows when the closing date was set or changed which can be helpful information for internal control. Pacman 2005 is a free remake of the famous game of the 1980s : a tiny yellow man must devour all the dots of a level avoiding his enemies, the ghosts. Battle For Aqua is a dynamic 3D scroll shooter with a space theme, where you fight for the planet, Aqua.
Sky Aces - Kampf der Reichsadler is an arcade aviation simulator dedicated to the events of WWI, and the airplanes participating in the conflict over the Western Front. This game is an attempt to reinterpret the famous Arkanoid with a new style, rhythmic music on each level and colorful lighting effects.


Your mission is to protect your tank and the base from the enemy tanks by destroying all enemy tanks. A dynamic and colorful Arkanoid in which you direct a small platform holding the ball within the playing field.
Pinball is a type of arcade game, usually coin-operated, where a player attempts to score points by manipulating one or more metal balls on a playfield inside a glass-covered case. Always thought you had what it takes to be a professional billiards player, but it just wasn't in the cards? One of the most publicized changes in QuickBooks version 2006 among accountants when it first came out was the change in voiding checks so the net effect is recorded in the current year. The theory of this approach makes Accountants very happy because no longer will voiding a check change the historical reports, most importantly, Retained Earnings.  Unfortunately, there are many limitations to how the process really works. One of the time consuming activities in the past was to enter the estimate for the customer then when they actually accepted the proposal, entering a purchase order to the vendor.  New with version 2004 this process is streamlined as part of Intuit"s NED2 (Never Enter Data Twice) Philosophy. By choosing the option to create purchase orders for selected items, the next pop up box permits sorting the items by preferred vendor as well as seeing the quantity on hand.  This streamlines the process even further by creating an interface where all the necessary information is available in the same place. Software development is rarely affected by the weather, for example, whereas you shouldn't begin excavating a cutting if the slope is soaking wet and subject to landslip.
Road building has been chosen as the example to compare against because it displays none of these characteristics, so distinctions can be drawn as clearly as possible. The twelve sections in this chapter each introduce one characteristic that is unique to software development, and explain its relationship to those already discussed.
Instructions usually appear as a single line in the text, but very complex instructions sometimes span two or more lines.
However, a program's complexity depends not just on the instructions, but also on the interactions between the instructions. These are sectioned off into small pieces (called objects) or somewhat larger pieces (called components), which are chunks of code that can be used without knowing exactly how they work. They are machines with far more moving parts than any engine: the parts don't wear out, but they interact and rub up against one another in ways the programmers themselves cannot predict. You can hold a floppy disk or CD-ROM in your hand, but the software itself is a ghost that can be moved from one object to another with little difficulty. We can visualize individual behaviors, but we have great difficulty visualizing large numbers of sequential and alternative behaviors. At its simplest level, chess is just a game where 32 pieces move from square to square across a board.
A road plan can show the exact location, elevation, and dimensions of any part of the structure. These individuals are experts in their own roles, but they rarely have as much experience as professional developers in dealing with the abstraction and complexity of software. This means that any specification of requirements for software is likely to be incomplete in important ways.
The software becomes less abstract to them once they can get hands-on experience and try out a variety of scenarios. As the software grows in functionality, the users can revise the remaining features based on their testing of the system under construction. The most honest response that a user can give is "I'll know what I want when I see it." However, as we'll see later, this consideration is rarely taken into account. The Standish Group [2001] identified problems with requirements and specifications as the top "Project Challenged Factors" for software projects. In the case of software, the building blocks are bits of software that do jobs that have been found useful in a wide range of situations. There are the one-person desktop applications that we're all familiar with, such as Microsoft Word for word processing, but there are also multi-user applications that run on an office network, such as accounting and email. Perhaps the best way to think of it is "as big as you want." Desktop applications are limited to running on one computer, but that's OK because only one person is using them at a time. For software, this distinction can often only be assessed some time after the software has been completed.
You cannot measure extensibility when the system is deployed, but it shows up the first time you must extend the functionality of the system. Numerous studies have shown that at least 50 percent of software cost goes into extending and modifying the original system [Koskinen 2004], and modifications to fragile code can be twice as expensive as modifications to robust and flexible code.
An architecture is the overall structure and design of a system, and can be seen as a codification of how to use the technologies that the system is built upon.
In event-driven programming, all a programmer does is write a few "event handlers," which are routines that respond to the user's actions.
If the programmer doesn't deliberately organize the program's code in a better way, then it all accumulates in this one routine, which ends up as a huge, unmanageable blob of code. A best practice is a process or technique that has a proven record of success in providing significant improvement to the results of an activity. Object-oriented programming has been in use since 1980, but it was only in 1995 that the "Gang of Four" (Erich Gamma, Richard Helm, Ralph Johnson, and John Vlissides) published their seminal book Design Patterns, which revolutionized object-oriented architectures and provided solutions to "anti-patterns" such as the Magic Pushbutton. A few architecture books are available already, but none of them are as significant as Design Patterns. We've seen how the building blocks for any new software would come from an enterprise application framework, and they would implement the most commonly used tasks that the software performs.
It's always cheaper to buy than to build, which is why a substantial marketplace has sprung up for software components that are more specialized than those available in the enterprise application frameworks. Since then, web services have become the preferred technology for accessing third-party software components.
New technologies supplant older ones every few years, and even more frequently, new versions of existing technology appear that radically change the functionality and use of that technology. Some of the tools work like they did in the previous version, but the majority are entirely new or have changed beyond recognition. Experience with these components can rarely be carried over into future projects, because those future projects are unlikely to use the same third-party components. The bulk of the technical knowledge required for a project will normally be learned on the job. There will be conceptual gaps that must be filled, and there will be assumptions that aren't justified and aspects that just won't work. Developers must combine analytical and creative skills to find out what their customer really wants (even if the customer's description is confused and incomplete) and invent ways to combine these requirements into a system that's logically consistent and easy to use. Traditionally, after in-house testing is completed, new software would be given to a small group of carefully chosen customers for beta testing in real-world conditions. This means that the first released version is known to contain bugs, and that customers are expected to pay for the privilege of testing it and finding the bugs. Even if the product chosen is mature and well regarded, and even if the developers have used it before, because of the complexity of software, you can rarely be sure that it can be used for the functions and circumstances that are unique to a particular project. The use of automation began during the Industrial Revolution in the eighteenth century, and hasn't let up any time since then.
But we're discussing projects here rather than production, and projects can never be wholly automated. But even beyond that, tools are constantly being developed and refined to automate new chores and responsibilities.
Web services use the industry-standard messaging language Extensible Markup Language (XML) to communicate messages over the Internet. The first step is to perform the planning and design, which results in a set of plans and blueprints that can be signed off.
The more definitive you try to make the plans, the more flawed they'll be, and the more labor there will be in revising them to meet changing circumstances. Indeed, there's no construction as such; there's only design on smaller and smaller scales. Each step requires the developer to analyze some portion of the problem and design some aspect of the solution.
If you discover during the course of a project that the foundations are in the wrong place, then it takes considerable effort to dig them out and rebuild them in another place. When you start digging, you may find that subsurface conditions are different from the original analysis. Indeed, they often do, as they learn more about what their nascent software can achieve for them.
Once we see change as inevitable, then the issue isn't one of avoiding change but of making change work to our advantage. The check is on the top with a voucher in the middle (which will stay with the check and go to the vendor) to detail the bills that are being paid. As during childhood, when a neighborhood boy introduced Tetris and then soon a line formed to play it. Pass through 11 levels, from the asteroid belt to final battles on the surface of the planet. At the beginning of the game you can choose any one of 12 aircraft to carry out the mission and shoot enemies.
You are the checkpoint Captain, with orders to resist and not give up under any circumstances. In fact, I have had a room full of Accountants actually cheer when they learned of this feature. However, this may not be the case for any other activities that come to mind, which might exhibit one or two, or even a few of these characteristics.
The concepts that appear further down on the diagram are derived from the more basic concepts shown at the top. A small program with one or two authors can easily run into tens of thousands of lines of code. An instruction may copy a piece of data, perform some arithmetic, manipulate text, or decide which parts of the program to execute (and in what order). The 100,000-line program has ten times as many instructions interacting with ten times as many instructions, so we should actually expect it to be a hundred times as complex.
By dividing these items into four smaller assemblages, the total number of interactions has been reduced from 66 to 18, and the system is now much less complex. We can think of each move as a piece's behavior, but any single move is meaningless in isolation. This is an important realization: any architecture, design, or diagram we create for software is essentially inadequate. They understand the business processes much better than the developers, of course, but even when someone has a good grasp of the main flows of behavior that are required, it's still very difficult to take into account all of the alternative flows and error conditions, and how different sets of requirements relate to each other. This is where the "steady stream of ‘essential' change requests" for the billing system comes from.


An expert can be brought in at any stage to perform usability testing, and to make recommendations regarding the user interface. Computers double in speed about every two years, and this opens up more and more opportunities for software developers.
Examples include getting data from a database, drawing a window on the screen, or converting dates from one format to another. The popular Internet search engine Google provides information to more than 1,000 people every second: no single computer could handle that load.
Sun's J2EE, which was perhaps the first true enterprise application framework to be widely used, appeared in 1998, and has seen considerable change since then. Hot-mix asphalt was patented in 1903, and that basic technology is still what we use today. This technology means that instead of having to write the core functionality for each new program over and over again, a programmer can just add functionality to an application skeleton that's provided for them.
Experience allows users to define best practices—in other words, the most consistent ways to use the technology well.
Fifteen years is a long time in the IT industry: many technologies have come and gone in less time.
This suggests that the enterprise application frameworks' best practices aren't mature yet. Later sections in this chapter will show how robust software can be created even in these circumstances, but it's not as simple as in road building, where the basic technologies have been around for much longer, and hence the best practices are long established and almost universally applied. These tasks are many and varied, and it comes as no surprise that the enterprise application frameworks themselves are huge and complex, containing tens of thousands of usable routines. Even when working on a variety of applications and systems, a developer will not be able to gain experience with more than a small proportion of the technologies that are available. Experience with enterprise application frameworks is similar; these frameworks are so extensive that different projects that use the same framework may well use totally different parts of it. Is it true that every significant new piece of software is written by developers who are essentially novices to the task? However, the "softer" skills that make one a good developer, or even a good team leader or architect, do apply from one project to the next, and can accumulate over time. Because clients aren't software experts, they won't always be able to distinguish between what's possible and what's not, or know what trade-offs are available. The rate of change in technology has been accelerating, and products are often released before they're mature, complete, or bug-free. You can't tell if it will do the job until you've actually made it do the job, and have seen that it works.
Sometimes it won't, but there's a workaround that takes more effort than originally planned.
We expect productivity gains in every industry, and software and road building are no exceptions. The Project Management Institute [2000] defines a project as "a temporary endeavor undertaken to create a unique product or service." It's this uniqueness that makes complete automation impossible.
To create a web service, you must define the message format for every possible type of message, to show how the data is to be converted into XML.
As the shape of the software becomes increasingly clear over the course of a project, the design of that software must be revised again and again.
But if tasks aren't repetitive, then defining them exhaustively becomes a time-consuming process.
This means that we can't easily categorize people into the roles of architect, designer, programmer, or analyst. For example, a piece of text can be stored in an unchangeable object for greater efficiency, or in a changeable object for greater flexibility. When a road is "realigned," what happens is that a completely new section of road is built alongside the old, which often remains as an alternative route. Subcontractors might not be available when you want them, and schedules may be adjusted accordingly.
If the software will never be changed, then why should we care if the software is fragile and badly designed as long as it still works? It includes design work to accommodate requirements whose details become clearer as the project progresses, and design work to reflect what's learned about the tools and components used to develop the software. In 8,000 large software projects analyzed in one study, some 40 percent of their requirements arrived after development had begun [Jones 1995].
If the process of development becomes one of extension and modification, then any software that resists change will have a difficult gestation.
The third section is a duplicate voucher to be kept, usually stapled to the bills being paid. While the theory is great, in practical application, there are some significant issues that need to be addressed. In their massive and immobile simplicity, they're as unlike software as it is possible to be. Significant products, like the latest versions of Microsoft Windows, run into tens of millions. There are also blank lines to separate groups of instructions, comments that explain to other programmers what these instructions are intended to accomplish, and elements that help define the structure of the program (components, objects, methods, etc.—please see the Glossary for more details).
This technique is known as encapsulation, and it is a key part of object-oriented programming. What gives it significance is its relationship to the moves that have gone before and to the moves that are yet to come. If we represent every detail, then we're merely duplicating the software in another form, and we're wasting our time and effort.
It's not that users don't know what they want: it's that they're just not able to visualize a system of this complexity until it's at least partially complete.
Software changes quickly—we all know that—but we may not be aware of just how quickly it changes, and what impact this has on any new software we try to build. Enterprise technology allows many computers to work together for a single application, and also provides the connectivity to allow lots of people to access it at the same time. For example, when Microsoft introduced "event-driven programming" to BASIC in 1991 via its new Visual Basic development environment, it provided powerful new capabilities, but also the potential for new problems. You can think of each routine as a knob, button, or dial that allows the application—and the developer—to control the workings of the framework, although there are also some routines that behave more like standalone tools. Instead of selling CD-ROMs, a third party keeps their software components on their own servers and makes them available over the Internet for a fee.
These skills include the software development best practices that are discussed later in this book. The advantages of being first to the market can outweigh the drawbacks of proffering flawed software.
No road is just like another, and even a piece of software that duplicates the behavior of another must be made in a unique way. The construction phase largely consists of well-defined, repetitive tasks that can be accomplished by less highly skilled workers. To completely redesign the solution each time around would be onerous and wasteful, so we should think rather of a process of ongoing design. A freeway interchange may be reworked over several years to suit changing traffic patterns, by the addition of permanent bridges, ramps, and lanes in a series of projects.
However, such changes rarely have an impact on the nature of the product: we don't expect to end up with a different building or a different road.
We expect that bugs can and will be fixed wherever they appear in the system, as indeed they are.
But most major systems are intended for long use—often decades—even if their underlying technologies rapidly become obsolete. The process of software development is one of continuous design, and therefore of continuous change. Poor changes are more likely to generate defects or bugs, and will make the code fragile and hard to debug. But numbers of lines of code may not mean much to you until you can relate that measurement to other types of complex systems. Even the foundations, which are hidden when the road is completed, can be viewed and touched as the road is being built. We have automatic tools that convert this representation into a program that the computer can execute.
But "enterprise" also means "as small as you want": enterprise application frameworks are not just for major applications in big companies. This makes it easy for the vendor to apply bug fixes and enhancements, and enables them to provide access to interesting data (stock quotes, news, retail price comparisons, etc.) as well as useful tools. Software is abstract, so defining the construction tasks completely is equivalent to actually performing the work, because automated tools are available that can turn such designs into working software. All developers have the same kinds of tasks to perform, even though some may have more responsibilities than others. Anyone who has written macros for Microsoft Office, or learned how to write small programs at school or at a university, knows how flexible software is and how quickly you can make substantial changes.
Over such long periods of time, the business environments will almost always see significant change. If a third-party software component isn't available on time, for example, then similar delays can occur. This means that software can only ever be described accurately at the level of individual instructions. They're harder to assess: you can't just boil them down to a list of buzzwords and acronyms. They frequently encounter setbacks and dead ends, simply because of the scope of the unknown. Developers no longer have to put any effort into defining the XML message formats for their web services, because this work is now done for them by their development tools.
To summarize is to remove essential details, and such details can (as we've all experienced) cause the software to fail catastrophically or—worse—subtly and insidiously.
In a very real sense, software projects are simply the process of discovering the unknowns: once the unknowns are known, then the project is effectively at an end.



The zohar secret film italiano
Secret story 4 desafio final 2


Comments Secrets of software success

  1. HsN
    Monastic lifetime of over two decades, Bhikkhu.
  2. Kitten
    Assist me cope with it particularly when.
  3. Xazar
    You'll find a button to obtain a?FREE within the.
  4. Jale
    Impressions From A 10 Leisure response meditation.they secrets of software success fall for writing about château's rooms are comfortable.