Variable and Datatype in Java

Variable and Datatype in Java

In this page, we will learn about the variable and java data types.Variable is a name of memory
location. There are three types of variables:local, instance and static. There are two types of
datatype in java, primitive and non-primitive.

Variable 

Variable is name of reserved area allocated in memory.

eg:   int data=50;  Here "data" is variable

Types of Variable

 There are three types of variables in java

Local Variable
A variable that is declared inside the method is called local variable.

Instance Variable
A variable that is declared inside the class but outside the method is called instance variable .
It is not declared as static.

Static variable
A variable that is declared as static is called static variable. It cannot be local.
We will have detailed learning of these variables in next blog.

Example to understand the types of variables

class A{

int data=50;//instance variable

static int m=100;//static variable

void method(){
int n=90;//local variable
}

}//end of class


Data Types in Java

In java, there are two types of data types

   1. primitive data types
   2. non-primitive data types

Data Type     Default Value     Default size

boolean              false                    1 bit
char                  '\u0000'                2 byte
byte                       0                     1 byte
short                      0                     2 byte
int                          0                     4 byte
long                       0L                   8 byte
float                       0.0f                 4 byte
double                   0.0d                8 byte