We can't promise you fame, fortune, or even a job if you learn the Java programming language. But it is likely to make your programs better, and it requires less effort than do other languages. We believe that the Java programming language will help you do the following:
- Get started quickly: Although the Java programming language is a powerful object-oriented language, it's easy to learn, especially for programmers already familiar with C or C++.
- Write less code: Comparisons of program metrics (class counts, method counts, and so on) suggest that a program written in the Java programming language can be four times smaller than the same program in C++.
- Write better code: The Java programming language encourages good coding practices, and its garbage collection helps you avoid memory leaks. Its object orientation, its JavaBeans component architecture, and its wide-ranging, extensible API let you reuse other people's code and introduce fewer bugs.
- Develop programs more quickly: Your development time may be twice as fast as writing the same program in C++. Why? You write fewer lines of code with the Java programming language, and it is a simpler programming language than C++.
- Avoid platform dependencies with 100% Pure Java™: You can keep your program portable by avoiding the use of libraries written in other languages. The 100% Pure Java™ Product Certification Program has a repository of historical process manuals, white papers, brochures, and similar materials online at: http://java.sun.com/100percent/
- Write once, run anywhere: Because 100% Pure Java programs are compiled into machine-independent bytecodes, they run consistently on any Java platform.
- Distribute software more easily: You can easily upgrade certain types of programs, such as applets, from a central server. Applets take advantage of the feature of allowing new classes to be loaded "on the fly," without recompiling the entire program.
Let's get started learning the Java programming language with a simple program, "Hello World." Depending on which platform you are using, you will want to read one of the next three sections: First Steps (Win32) (page 8) gives detailed instructions on compiling your first program on the Windows platform, First Steps (UNIX/Linux) (page 16) has instructions for the UNIX and Linux platforms, and First Steps (MacOS) (page 24) covers the MacOS platforms. Then don't miss the section A Closer Look at HelloWorld (page 32), which explains some basic features of the Java programming language as demonstrated in the HelloWorld program.