Java Data Types

Java Data Types
 

What is Data Type?
 

Data type is a classification of the type of data that a variable or object can hold in computer programming.

Ex: character, integer, float etc....

> Java supports explicit declaration of Data types.
(we need to specify the data type before declaring the Variable)

Syntax:data_type variable_name;

data_type variable_name = value;

Example:
int a;

int a = 100;
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Two types of Data types in java:


a) Primitive Data types

b) Non-primitive Data types / Reference Data types
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a) Primitive Data types (8 primitive data types)

Integer types1) byte (8 bits)

Ex:

byte a =100;

2) short (16 bits)

short a = 10000;

3) int (32 bits)

int a = 100000;

4) long (64 bits)

long a = 100000L
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Rational types (Numbers with decimal places)5) float (32 bits)

float a = 1.2;

6) double (64 bits)
ex:
double a = 19.3456;
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Characters7) char (16 bits)

Ex:

char a ='Z'
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Conditional8) boolean (undefined, depends on JVM)

Ex:
boolean a = true
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b) Non-primitive / Reference data types
 

Non-primitive data types in Java are Objects and Arrays.

Note:

Reference types are not passed value, passed by reference

Ex:

Button a = new Button("OK")
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Java String:

> Java String provides a lot of concepts that can be performed on Strings.

> Java String is not a data type in Java, It is a Class.

Declaring String variables and Arrays:

String myTool = "Selenium"; // String Variable

String [] myTools = {"Selenium", "UFT", "RFT", "SilkTest", LoadRunner"}; Array of Strings
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Also Read:

Java Variables

Java Operators 

Java Conditional Statements 

Java Loop Statements

Java Arrays 

Java Methods

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