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History: Sun Microsystems originally created a small language called "Oak" to be used
in devices such as microwave ovens. Eventually, they realized they had a considerably more diverse and robust
languange in Oak. Soonafter they renamed it "Java", and started to market it as a general purpose
language created by Netscape to be used as an additon to HTML. It was originally called "LiveScript",
and the name change was a marketing ploy to redirect some of the "buzz" centered around Java towards
Java has been considered the forerunner to replace C++ as the most widely used programming language. This is in no small part due to the relative ease with which Java can create GUIs (Graphical User Interfaces).
The Programming Language: To write any program, you must either understand the machine
code of your computer, or use a "high level" language such as Java. With these higher level
languages we start by using a text editor (such as pico) to enter our program into a file.
This file, which is in English words and phrases, must then be changed into "machine code" a language
which can be best described as ones and zeros. This is the language computers really understand, not
English (or Spanish, or French, etc.)
To get this machine code, we first convert the original file into
"bytecodes" by "compiling" the source code.
You compile code by typing "javac" (no quotes) followed by the source file name.
The compiler will create an executable file with the same name as the source code and a ".class"
A software package called the Java Virtual Machine (JVM), then
converts the file with bytecodes into machine code during program execution.
You invoke the JVM by typing "java" (no quotes) followed by the first part of the executable file name (i.e. without the ".java" extension).
Questions? e-mail: consult