The Awesome Power of PowerJ

Tim Hatton

1998 | 378 pages
ISBN: 1884777538
$43.95 Softbound print book  

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DESCRIPTION

PowerJ is the bridge between the rapid application development world of PowerBuilder and the multiplatform world of Java. The Awesome Power of PowerJ show you how you can write Java programs the very first day with PowerJ, even if you don't know Java. Through a hands-on approach that makes liberal use of figures and code snippets, you will learn how to use PowerJ to build effective Java applets and applications.

Whee you're an IS manager considering Java, a webmaster looking for a fast way to write and deploy Java code or a developer with a hot Java project, you need this book. What's inside:

WHAT THE EXPERTS SAY ABOUT THIS BOOK...

"... well organized, easy to read and to the point. The chapter on database interaction with Java was especially useful."
-Tonya Pope, Virtual Reality Manager, Main Street Multimedia

"... covers its subject in a clear and userful manner. I read the entire book in a single sitting: a high compliment indeed."
-Mark Mitchell, Development Director, Silicon Graphics

"I liked the author's informal writing style ... anyone interested in PowerJ from beginner through advanced will find this book useful."
-David Miller, Rippe & Kingston Systems, Inc.

ABOUT THE AUTHOR...

Tim Hatton is a principal of CreativeSoft, Inc., an early user of the Power++ product upon which the PowerJ interface is based. He has many years of experience as a developer of real-world applications using PowerSoft products.

Introduction

Welcome to the world of Java programming using PowerJ, a Rapid Application Development tool from Powersoft, the makers of PowerBuilder. With PowerJ, Powersoft does for Java programming what they did for client-server development with PowerBuilder - they make it easy and fast.

With PowerJ, you can write Java programs the very first day even if your Java experience is limited. This is made possible by an award-winning drag-and-drop programming interface (first used by PowerSoft in their Optima++ C++ development environment) that actually uses a Wizard to construct Java language statements for you and pastes those statements into a code editor window. Since these statements are constructed by PowerJ itself, they are error free.

Of course, you still need to know programming since you will be required to use flow control statements such as if? else or while to control the execution of your code, but the real guts of the Java language are hidden from you.

That is not to say that PowerJ is a beginner's-only environment. PowerJ will serve the needs of every level of developer. Beginners can rely heavily upon the assistance of the drag and drop interface while advanced Java developers can use the code editor to write the code directly. And everybody can benefit from the debugging features and the form design features that make development using PowerJ a snap.

Who should read this book

This book is for beginning and intermediate Java developers who want to learn or get up to speed on developing Java applications using PowerJ. It is also for those who do not know Java, but still want to be able to deliver Java applications. PowerJ excels at teaching you Java as you go.

Aside from the Java basics chapter, little time is spent teaching you the syntax of the Java language (many books have been written about that) and most of the focus is put on how to accomplish a task using the PowerJ product.

If you are a beginning Java programmer you should start your reading with Chapter One, the Java Basics chapter.

If you are already familiar with both Java and object oriented programming concepts you can start with Chapter Two, which is an overview of the PowerJ Integrated Development Environment. And if you are familiar with both Java and the Power++/PowerJ environment (from using Optima++), you can start with Chapter Three which begins the in-depth exploration of how to use PowerJs to develop Java applications.

So What is Java All About?

It's hard to believe that just a few short years ago Internet access was the domain of a relatively few academic organizations and "computer people." Today, nearly 40% of the American people are on the Internet in one form or the other.

So, what has made the Internet so popular? In a word, multimedia. It is the promise of wonderful multimedia content, delivered right to your home or office, on demand, that fueled the print and broadcast media's hype of the Internet and attracted all those new users.

The trouble is, until just a couple of years ago the ability to easily create and deliver that content did not exist. The ability to move massive amounts of data across small copper wires at modem speeds served as a sever constraint to the development of real multimedia broadcast capabilities and still does (although the problem is beginning to be solved). But the available bandwidth was only a small part of the problem.

The problem was that there was no development tool that had the ability to run on the many different client computers that end users were using to access the Internet. Not to mention the multiple operating systems that were available for each hardware platform.

Enter Java

Responding to this need, the developers at Sun created the Java language. One use of Java is to deliver true cross platform development capabilities by transmitting a form of the code itself to each client, where it is executed in a virtual machine. The virtual machine is different for each platform, taking advantage of each platform's capabilities. The only thing that remains the same is that the virtual machine can execute the Java code that it sent to it. The code is the same for all clients and the virtual machines can execute it.

Of course, all this is possible using methods other than Java. Programs can be written for the CGI interface that can do anything a Java application can do. But there are differences and drawbacks. One is that CGI programs execute on the server and only the result of that execution is sent to the client. Also CGI, has the reputation of being hard to learn.

More than pretty graphics But if Java was just a language for delivering multimedia content, it is doubtful that it would be as popular as it is now becoming. The fuel that is now feeding the Java fire is its use as a multi-tiered, business application development language. Java applets and applications are being used to deliver business related contentd over the internet. These applications play off of Java's strength as a multi-platform development language. Business can write real-time database driven applications and use Java's cross-platform support to deliver that content vis the Internet to users world wide. No matter what network they use, no matter what hardware, no matter what web browser.

With Java, you write it once and deliver it to many locations, without change.

Why Learn Java?

Java is the hottest language to hit the computer industry in the past ten years. Fueling the fire to make Java hot is the phenomenal rate of growth of the internet. As the internet continues to grow at a rapid pace, demand for Java development, the glue that makes all those glamorous web pages work, will also continue to increase exponentially. although Java is a general purpose language that has uses for beyond the Internet, relatively it is the Internet uses that are driving Java's growth. For traditional applications there are other mor entrenched languages.

But being a C++-derived language makes Java difficult to read, understand and write for many developers. Several products have been released from the major players in the industry to enable Rapid Application Development for the Java developer. Microsoft's Visual J++ and Symantec's Cafe are examples.

Each of those products was a step in the right direction, but they fail to deliver the full promise of Java based RAD to the masses of programmers who do not already know C++. PowerJ is different. Its unique interface finally delivers RAD Java Development to the masses.

Why Learn PowerJ?

The PowerSoft Corporation, (now part of Sybase) is author of one of the biggest success stories of the 1990's - PowerBuilder. PowerBuilder was the first product that delivered true RAD for the client/server programmer. With its unique datawindow architecture, PowerBuilder all but cornered the market on client/server development. Now PowerSoft will try to do it again with PowerJ, their new Java RAD tool.

PowerJ is derived from PowerSoft's Power++ which is a full blown C++ development tool. Most of what is discussed in this book will be familiar to those who have programmed using Power++. In fact, both products use the same user interface so you can develop code in C++ or Java with the same ease of use.

Why use PowerJ to Develop your Business Applications?

As more and more shops enter the Java world managers are increasdingly faced with the decision of what environment to use to develop their Java programs. PowerJ should be given serious consideration.

Why? Mostly because of its ease of use. Java is new in terms of programming languages. While you may have C++ programmers on staff or you may have PowerBuilder programmers on staff, it is unlikely that you will have Java experts on staff. What you probably will have are some developers that are proficient in other languages who have learned Java on the side. They know the basics of Java and they know programming constructs, but they are not really Java experts.

Since you probably need to get your Java programs written and deployed sooner rather than later, you are faced with the need to either train your staff extensively before beginning development or to hire new, Java proficient developers. PowerJ will give you the best of both worlds. With PowerJ you can bring your existing developers up to speed on Java at the same time that they are delivering real world Java applications.

The more they use PowerJ the more they will learn Java. The key is to build your smaller applications first and move into the more complex applications as your developers gain knowledge (but isn't that true of any language. Shops that attempt to use a new language to completely re-write their business processes in one shot seldom succeed unless they go outside for help).

Finally, a Note About Using the Mouse

Since PowerJ is a drag-and-drop environment you will use the mouse extensively. So there will be many times when I tell you to click something or to drag something and drop it somewhere else. When I say click something, I mean to use the left mouse button. When you need to use the right mouse button, I always will say to right click. Doubleclicks always mean use the left button. When I say to drag something I mean to click it with the left button and move the mouse to the new location and then relase the left button.

Of course, if you have a left-handed mouse all this is reversed.

With all that in mind, let's get started on our way to learning Java programming with PowerJ.