Variables and Data Types in Java

Variables:

A variable is a name given to the value. For Example: Where, int i =10;

• int= Data Type
• i = Variable
• 10 = Value
• semicolon(;) is given after the end of the action.

Types Of Variables:

Static Variable

Instance Variable

Local Variable




Let’s know little deeper about Java training institute in Chennai




1.What is Static Variable?

Static Variable is a class level Variable

It can be accessed within the class only

Static Variable can be accessed without the use or creation of an object.

For Static Variable, We have to mention Static

For Example: static int i = 10; static String st= ” NAME”;




2.What is Instance Variable?

Instance Variable is not like Static Variable.

No need to mention any Instance

It’s a copy of its own instance variable




3.What is a Local Variable?

Local Variable is Method Level variable, Java training institute in Chennai

It can be accessed within the method only.

To call the local variable, we have to create an object.

It cannot be accessed outside the method.




So I have covered mostly all variable types …… So let’s jump into another topic is Data Types






Data Types In JAVA




Types of Data Types in Java:




Data Types are classified into two types, they are:




Primitive Data Type

Non-Primitive Data Type




Primitive Data Types:




Primitive Data Types are classified into Eight types of Core java training in Chennai.


Byte

Short

Int

Long

Float

Double

Boolean

Char

Non-Primitive Data Types:




Non-Primitive Data Types are classified into two types. they are:




Arrays

Strings




Primitive Data Type:




Byte:

For Storing whole Numbers

It stores a value between -128 to 127

Size = 1 byte

Value = 0

Short:

For Storing Whole Numbers

It stores value between -32,768 to 32767

Size = 2 byte

Value = 0

Int:

For Storing Whole Numbers

It stores value between -2,147,483,648 to 2,147,483,647

Size = 4 byte

Value = 0

Long:

For Storing Whole Numbers

It stores value between 9,223,372,036,854,775,808 to 9,223,372,036,854,775,807.

Size = 8 byte

Value = 0

Double:

It is used for Fractional Numbers

It stores upto 15 decimal digits

Size = 8 byte

Value = 0

Float:

It is used for Fractional Numbers

It stores upto 7 decimal digits

Size = 4 byte

Value = 0

Boolean:

It is used to tell either true or false

Char:

It is used in character

Size = 2 bytes


For Example:

int i = 10; byte b = 5; short s = 10; long = 123l; float = 23.9f; double = 34.98d; or 34.98 boolean = true; or false; char = ‘A’;




Non-Primitive Data type:




Array:




Array is classified into two types:




1.Single-Dimension Array

2.Multi-Dimension Array

String:

String is a collection of character

It can be initialized into double quotes

For example:




String st=”My Name”;





I hope this will be helpful for the beginners in java ...See you in the Next topic. core java training in chennai