First Java Program

Class 1, Part 2

Intro to Java 30-IT-396

Numbers without a Fraction

Store both positive and negative values. But, no decimal.
Optimize the memory for numbers that do not need fractions. Ideal for that use. Examples:

Counters
Day of month
Age
Number of Employees

The only real difference is memory size.

Primitive Type	Size	Range
int (most popular)	4 bytes	-2,147,483,648 to 2,147,483,647
short	2 bytes	-32,768 to 32,767
long	8 bytes	-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807
byte	1 byte	-128 to 127

Those numbers might sounds large, but just wait until you have an overflow!

Hash totals, for example.

Food for thought: why is the negative value one greater than the positive value in each case?

Floating Point Types

Created by: Brandan Jones December 17, 2001