This trail covers the fundamentals of programming in the Java language.
Object-Oriented Programming Concepts cuts through the hype surrounding object-oriented technology and teaches you its core concepts: objects, messages, classes, and inheritance. You need to understand these concepts before learning how they are applied in the Java language. This lesson contains a bibliography for further reading on the subject. Feel free to skip this lesson if you are already familiar with object-oriented programming.
The Nuts and Bolts of the Java Language explains a simple Java program line by line. Following this example, you will read about the syntax and semantics of the Java language.
Because Java's syntax is similar to that of other programming languages, particularly C and C++, much of this material will be familiar to seasoned programmers. You may wish to skim this lesson for its main points and use it as a reference.
Objects and Classes in Java shows you how Java implements the concepts described in the first lesson of this trail. You will learn how to create, use, and destroy objects and how to write the classes from which objects are created. The last section introduces you to the
Spotapplet and uses it to discuss the practicalities of subclassing another class, implementing an interface, and using an inner class to implement an adapter class. Every Java programmer needs to be facile with the technology presented by this lesson.
More Features of the Java Language is a lesson about family planning. The topics discussed here-inheritance, interfaces, nested classes, and packages-are all features of the Java language that help you to organize and structure your classes and their relationships to one another. This lesson not only shows you how to use these features of Java, but also talks about when and why you would use them.
If you don't need this information right away and want to get on with the business of writing some applets, feel free to leave this lesson for later and go straight to the next trail, Writing Applets.
Common Problems (and Their Solutions) explains the solutions to some problems you might run into while learning the Java language.