Sams Teach Yourself Visual J++ 6 in 21 Days
(Publisher: Macmillan Computer Publishing)
Author(s): Rick Leinecker
ISBN: 0672313510
Publication Date: 11/01/98

Introduction

Visual J++ is an important addition to software developers’ tools. You can use it to create amazing Java applets for Web sites. These applets can take static HTML and bring it to life with animations, professional-looking user interfaces, and real-time display based on current data. Besides Java applets, Visual J++ gives you a viable alternative to using Visual C++ and Visual Basic for building applications. Visual J++ is a truly object-oriented language. For this reason, many software developers who are more comfortable with object-oriented approaches will choose it for their programming tasks.

I’ve tried to give you the information you need in this book yet keep it free of boring and overly technical discussions. Many authors throw the kitchen sink into every example, and it’s hard to pick out the code that’s related to the topic at hand. To avoid this situation, I keep examples simple and limit them to the current topic.

I’ve created a section on my Web site that will contain updates and answers to questions that readers send me. You can find the section if you go to www.infinitevision.net and follow the links to Books and then Learn Visual J++ 6 in 21 Days.

Feel free to email me at ivt-rcl@interpath.com. Remember, though, I’m a software developer and I might be in the middle of a project! During these times, I’m very busy. I can usually answer emails in a day or two, but during crunch times it might be closer to a couple of weeks.

Who Should Read This Book?

This book covers everything you need to bring you from no experience to a point at which you’ll easily be able to create applications and applets with Visual J++. As a matter of fact, if you are conscientious and read one chapter each day, you’ll amaze yourself at how good you’ll get at Visual J++ programming.

Here’s who should read this book:

•  Web developers who want to jumpstart their sites by creating Java applets.

•  Programmers who feel comfortable with object-oriented programming and want to use Visual J++ to develop applications.

•  Developers who like some of the things Visual J++ has to offer, such as easy imaging and image-processing methods.

•  Programmers who want to take advantage of the explosion in distributed computing and participate in Web-based solutions.

•  Those who are going to teach Visual J++ for a class or seminar and want an organized approach to covering the material.

If you find yourself in any of these categories, this book is for you.

What This Book Contains

This book contains 21 days’ worth of lessons—one lesson per day. Each chapter is designed to be read in a single day. It’s like a course in Visual J++ that you can read and study on your own time and at your own pace.

This is not a reference book that’s full of lists and dry class and method descriptions. It attempts to be like a friendly instructor who wants you to learn how to program with Visual J++. For lists and class and method descriptions, you can use the online help. You’ll find that for learning Visual J++, though, the discussions in this book are clear and easily understood.

I start by teaching you introductory topics you need, such as how to create and edit projects. Then, you’ll learn the basics of user-interface objects, such as editable text fields and menus. A section on graphics comes next—this is my personal favorite! Then, you’ll learn some of the nuts and bolts of Visual J++ programming in an elements section that covers topics such as exceptions and strings. The last section covers more advanced topics, such as ActiveX controls and how to use J/Direct.

What You Need in Order to Begin

The main thing you’ll need is Visual J++ 6. If you bought Visual Studio 6, you have a copy. You can also download a copy from Microsoft’s Web site. To download a copy of Visual J++, go to www.microsoft.com/VisualJ. Then, follow the links to the Visual J++ download page.

If you’re developing Java applets, you can run them on your local computer. But it’s helpful to have a Web site to which you can upload applets and test them in a live environment.

Your 21 Days at a Glance

Day 1 gets you started. You’ll learn about the Visual J++ environment, and how to create and build projects. You’ll create and build two programs to get you going.

Day 2 teaches you about the Java language. You’ll learn about variables, control statements, and expressions. This all-important chapter gives you the knowledge you need in order to understand the syntax of Java.

Day 3 shows you how to make your applets live on the Web. You’ll learn about Web directory structure and HTML tags for applets.

Day 4 shows you how to debug Visual J++ programs. This might be one of the most important topics in the book because it will help you figure out what’s wrong when something doesn’t work.

Day 5 introduces windows. On this day you’ll learn how to create and manipulate windows. You’ll also learn about window events. Finally, you’ll learn about some important object-oriented topics, such as classes and method overriding.

Day 6 shows you how to create and use menus. At the end of Day 6 you’ll have no trouble using these important user-interface items.

Day 7 shows you how to create and use user-interface components in Visual J++ applets. Items such as combo boxes, list boxes, and editable fields are covered in full detail.

Day 8, similar to day 7, shows you how to create and use user-interface components in Java applications. Handling events generated by these items is also covered in detail.

Day 9 shows you how to create dialog boxes in Visual J++ applications and interact with them from the main program. Visual J++ makes dialogs a snap, and this chapter teaches you how.

Day 10 starts the graphics section. You’ll learn about fonts and text. How to create fonts of different sizes and colors. How to center text in a window.

Day 11 shows you how to draw to your program’s window. Lines, rectangles, ovals, and the like are all covered.

Day 12 is about images. Visual J++ makes loading and using images easy. This chapter brings you through the methods for applications and applets.

Day 13 teaches you about image processing. It’s an important subject, especially if it reduces the number of files on a Web server and the amount of data that must be sent over the phone line to users.

Day 14 might be your favorite. It covers animation—most developers really enjoy this topic. You might get creative and build some great animation programs.

Day 15 covers the all-important topic of exceptions. This might be a new topic to many readers, making this chapter all the more important.

Day 16 deals with the topic of mouse input. You’ll learn how to get and receive mouse events.

Day 17 teaches you how to create and use threads. It’s a fairly advanced subject but one that all Visual J++ programmers will eventually need.

Day 18 covers the topic of strings. Strings are used in almost every part of Visual J++ programming, and this chapter covers the topics thoroughly.

Day 19 teaches you about stream I/O. You’ll learn how to read from disk files and how to copy files.

Day 20 is about ActiveX. This buzzword crops up in just about every article about Windows computing. And this chapter gives you the know-how to understand and make use of the concepts.

Day 21 covers an advanced but important topic: J/Direct. This feature was added to Visual J++ to give programmers greater power and flexibility.

Conventions Used in This Book

This book uses different typefaces to differentiate between code and regular English, and also to help you identify important concepts.

•  Actual code is typeset in a special monospace font.

•  Italic highlights terms when they first appear in the text and is sometimes used to emphasize important points.

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Note:  Note boxes give you information that is especially important. Sometimes they provide extra information that helps you understand a topic better.

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Tip:  Tips give you ways to make something better or make a process easier.

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Caution:  Warnings indicate something you should be aware of to avoid malfunctions or problems.

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The Input icon marks the beginning of a section of source code that gives an example of something talked about in the text.

The Output icon marks a section that describes or shows a screen shot of a program in operation.

The Analysis icon marks the beginning of a section in which a program is analyzed. These sections are important for your understanding of the topic.

When new terms are introduced in the text, many times they’ll show up with a New Term icon.