Lesson 2. The ABCs of Programming

A Java program is made up of classes and objects, which are made up of methods and variables. Methods are made up of statements and expressions, which are made up of operators.

At this point, you might be worried that Java is like a set of Russian nesting matryoshka dolls. Each doll has a smaller doll inside it, as intricate and detailed as its larger companion, until you reach the smallest one.

This lesson clears away the big dolls to reveal the smallest elements of Java programming. It sets aside classes, objects, and methods and examines the basic things you can do in a single line of Java code. The following subjects are covered:

Statements and expressions

  • Variables and primitive data types

  • Constants

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