A variable provides us with named storage that our programs can manipulate. Each variable in Java has a specific type, which determines the size and layout of the variable's memory; the range of values that can be stored within that memory; and the set of operations that can be applied to the variable.
You must declare all variables before they can be used. Following is the basic form of a variable declaration -
data type variable [ = value][, variable [ = value] ...] ;
Here data type is one of Java's data types and the variable is the name of the variable. To declare more than one variable of the specified type, you can use a comma-separated list.
Following are valid examples of variable declaration and initialization in Java -
int a, b, c; // Declares three ints, a, b, and c. int a = 10, b = 10; // Example of initialization byte B = 22; // initializes a byte type variable B. double pi = 3.14159; // declares and assigns a value of PI. char a = 'a'; // the char variable a iis initialized with value 'a'