Java Variables | Java Tutoeial | Java Variable Example

Java Variables

A variable is a holder which holds the esteem while the java program is executed. A variable is alloted with a datatype.

Variable is a name of memory area. There are three kinds of factors in java: neighborhood, occurrence and static.

There are two kinds of information types in java: crude and non-crude.

Variable

Variable is name of held zone assigned in memory. As such, it is a name of memory area. It is a mix of "fluctuate + capable" that implies its esteem can be changed.

int data=50;//Here data is variable

Types of Variables

There are three types of variables in java:

• local variable
• instance variable
•  static variable

1 Local Variable

A variable announced inside the body of the strategy is called neighborhood variable. You can utilize this variable just inside that strategy and different strategies in the class aren't even mindful that the variable exists.

A nearby factor can't be characterized with "static" watchword.

2 Instance Variable

A variable pronounced inside the class however outside the body of the strategy, is called case variable. It isn't pronounced as static.

It is called example variable since its esteem is occasion explicit and isn't shared among occurrences.

3 Static Variable

A variable which is proclaimed as static is called static variable. It can't be neighborhood. You can make a solitary duplicate of static variable and offer among every one of the examples of the class. Memory allotment for static variable happens just once when the class is stacked in the memory.

Example to understand the type of variable in java

class A{  int data=50;//instance variable  static int m=100;//static variable  void method(){  int n=90;//local variable  }  }//end of class

Java Variable Example :- Add Two Number

class Simple{      public static void main(String[] args){      int a=10;      int b=10;      int c=a+b;      System.out.println(c);      }}

OutPut :-

20

Java Variable Example :- Widening

class Simple{  public static void main(String[] args){  int a=10;  float f=a;  System.out.println(a);  System.out.println(f);  }}

OutPut :-

10 10.0

Java Variable Example :- Narrowing (Typecasting)

class Simple{      public static void main(String[] args){      float f=10.5f;      //int a=f;//Compile time error      int a=(int)f;      System.out.println(f);      System.out.println(a);      }}

OutPut :-

10.5 10

Java Variable Exmple :- Overflow

class Simple{      public static void main(String[] args){      //Overflow      int a=130;      byte b=(byte)a;      System.out.println(a);      System.out.println(b);      }}

OutPut :-

130 -126

Java Variable Exmple :- Adding Lower Type 

class Simple{  public static void main(String[] args){   byte a=10;  byte b=10;  //byte c=a+b;//Compile Time Error: because a+b=20 will be int  byte c=(byte)(a+b);  System.out.println(c);  }}

OutPut :-

20