Basic Skills for Working with Data
The Eight Primitive Data Types
| Type | Bytes | Use |
|---|---|---|
| byte | 1 | Very short integers from -128 to 127 |
| short | 2 | Short integers from -32,768 to 32,767 |
| int | 4 | Integers from -2,147,483,648 to 2,147,483,647 |
| long | 8 | Long integers from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 |
| float | 4 | Single-recision, floating-point numbers from -1.7E308 to 1.7E308 with up to 16 significant digits. |
| char | 2 | A single Unicode character that's stored in two bytes. |
| boolean | 1 | A true or false value. |
How to declare and initialize a variable in two statements Syntax:
type variableName.
variableName = value;
Example:
int counter;
counter = 1;
Syntax:
int counter = 1;
Examples:
double price = 14.95;
float interestRate = 8.125F;
long numberOfBytes = 2000L;
int population = 1734323;
int popluation = 1_734_423;
double distance = 3.65e+9;
char letter = 'A';
char letter = 65;
boolen valid = false;
int x = 0, y = 0;
To declare and initialize more than one variable for a single data type in a single statement, use commas to separate the assignments. To identify float values, you must type an f or F after the number. To identify long values, you must type an l or L after the number.