Data and Expressions - Java Software Solutions: Foundations of Program Design - page 75

SR 2.15 How many values can be stored in an integer variable?
SR 2.16 What are the four integer data types in Java? How are they different?
SR 2.17 What type does Java automatically assign to an integer literal? How
can you indicate that an integer literal should be considered a different
type?
SR 2.18 What type does Java automatically assign to a floating point literal?
How can you indicate that a floating point literal should be considered
a different type?
SR 2.19 What is a character set?
SR 2.20 How many characters are supported by the ASCII character set, the
extended ASCII character set, and the Unicode character set?

2.4 Expressions

An expression is a combination of one or more operators and oper-
ands that usually perform a calculation. The value calculated does
not have to be a number, but it often is. The operands used in the
operations might be literals, constants, variables, or other sources
of data. The manner in which expressions are evaluated and used is
fundamental to programming. For now we will focus on arithmetic
expressions that use numeric operands and produce numeric results.

KEY CONCEPT
Expressions are combinations of
operators and operands used to
perform a calculation.

Arithmetic Operators
The usual arithmetic operations are defined for both integer and floating point
numeric types, including addition ( + ), subtraction ( - ), multiplication ( * ), and divi-
sion ( / ). Java also has another arithmetic operation: The remainder operator ( % )
returns the remainder after dividing the second operand into the first. The remain-
der operator is sometimes called the modulus operator. The sign of the result of a
remainder operation is the sign of the numerator. Therefore:

Operation Result

17
-20
10
3

% 4
% 3
% -5
% 8

1
-2
0
3