variable_type variable_name = variable_value;
String: store text and are enclose by double quotes
String fruit = "Apple";
Int: stores whole numbers (integers) without decimals
int x = 5;
float: stores decimal numbers (floating points) such as 5.6, 12.2
float myFloat = 12.2;
char: stores single upper-case or lower-case characters such as 'A' or 'b'. the characters
char myChar = 'A';
boolean: stores values with two states, true or false
boolean isRaining = true; boolean notRaining = false;
Picking the name for a variable
- Cannot user special characters such as % $ # ? or space.
- You cannot use reserved words like double or class.
- Names are case sensitive.
- Variable names must start with a letter or underscore (_) character, and the remaining characters must be letters, numbers, or underscores.
- Use Camel case. It uses uppercase letters to denote word boundaries, as in isRaining from the example above.
Names by Java convention:
- Variable names start with a lowercase letter.
- Class names start with an uppercase letter.