The Writing Java Programs series covers everything you need
to know about the Java language. In addition, some of the lessons
describe the use of classes in the java.lang package.
Object-Oriented Programming Concepts: A Primer
cuts through all the hype surrounding object-oriented technology and teaches you
its core concepts: objects, messages, classes and inheritance. It's important to
understand these key concepts before delving into the specifics of the Java language.
This lesson also 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 Anatomy of a Java Application
talks about the
components of a stand-alone Java program in the context of
a small application that prints the current date and time.
Through this lesson, you will see classes and objects, two
fundamental building blocks of object-oriented programming,
in action within the context of a Java program.
The Nuts and Bolts of the Java Language
introduces you to several components of the Java language
by explaining a simple Java application line by line. You will learn
about the syntax and semantics of the Java language, plus several features
of the Java programming environment.
Objects, Classes, and Interfaces
takes the concepts that you learned in Object-Oriented Programming Concepts: A Primer
and walks you through how to make use of those concepts in the Java language. You will
learn how to create, use and destroy objects, how to write your own classes, including information
about writing methods and creating subclasses, and you will learn how to create and use
interfaces. This lesson is a complete do-it-yourself "Object-Oriented Programming in Java" lesson.
The String and StringBuffer Classes
illustrates how to manipulate character data using
the String and StringBuffer classes. Through this lesson you will
also learn about accessor methods and how the compiler uses Strings and
StringBuffers behind the scenes.
Command Line Arguments
shows you how to accept and process
arguments provided on the command line to a Java application.
Note that the Java interpreter only passes command line arguments
to Java applications--applets use parameters instead.
For more information about applet parameters, see
Defining and Using Applet Parameters
Threads of Control
discusses in detail the use of threads that enable your Java
applications or applets to perform multiple tasks at
the same time. This lesson describes when and why you might
want to use threads, shows you how to create and manage threads
and thread groups in your Java program, and shows you how to
avoid common pitfalls such as deadlock and race conditions.
Handling Errors using Exceptions
discusses how you can use Java's exception mechanism to handle
errors in your programs. In this lesson you will learn what an exception is,
how to throw and catch exceptions, what to do with an exception once you've
caught it, and how to best use the exception class hierarchy provided by the
Java development environment.
Input and Output Streams
begins with a description of your likely first encounter with Java I/O streams.
Then this lesson provides an overview of the InputStream and OutputStream family
of classes. From there, this lesson provides many examples of how you to use the
most "popular" I/O streams, including two examples on how to write your own filtered
streams.
