What to Install on Your Computer to Create Java Programs
A Java programmer uses existing programs as tools to create new programs. The existing programs and new programs might perform very different kinds of tasks. For example, a Java program (a program that you create) might keep track of a business’s customers.
To create that customer-tracking program, you might use an existing program that looks for errors in your Java code. This general-purpose error-finding program can find errors in any kind of Java code — customer-tracking code, weather-predicting code, gaming code, or the code for an app on your mobile phone.
So how many tools do you need for creating Java programs? As a novice, you need three tools:
You need a compiler.
A compiler takes the Java code that you write and turns that code into something that can run on your computer.
You need a Java Virtual Machine (JVM).
A Java Virtual Machine runs your code (and other peoples’ Java code) on your computer.
You need an integrated development environment (IDE).
An integrated development environment helps you manage your Java code and provides convenient ways for you to write, compile, and run your code.
To be honest, you don’t actually need an integrated development environment. In fact, some developers take pride in using plain, old text editors such as Windows Notepad or the vi editor in UNIX. But, as a novice developer, a full-featured IDE makes your life much, much easier.
The World Wide Web has free, downloadable versions of each of these tools. By clicking a button on a Java.com page, you install a Java Virtual Machine on your computer. At Eclipse, you download the Eclipse integrated development environment, which comes with its own built-in Java compiler. (You get two of the three tools in one download. Not bad!)