Variables in Java

title: Variables in Java description: Java mein variables kya hain aur kaise declare karte hain

Variable kya hai?

Variable ek named memory location hai jisme data store hota hai.

Variable Declaration

java exampleWoHoTech

dataType variableName = value;
int age = 25;
String name = "Rahul";
double salary = 50000.50;
boolean isStudent = true;

Variable ke Types

1. Local Variable

Method ke andar declare hota hai
Sirf us method mein accessible
Default value nahi hoti, initialize karna zaruri

java exampleWoHoTech

void myMethod() {
    int x = 10; // local variable
}

2. Instance Variable

Class ke andar, method ke bahar
Har object ka apna copy
Default value milti hai

java exampleWoHoTech

class Student {
    String name;  // instance variable
    int age;
}

3. Static Variable (Class Variable)

static keyword se declare
Sabhi objects share karte hain
Class load hone par create hota hai

java exampleWoHoTech

class Counter {
    static int count = 0;  // static variable
}

Variable Naming Rules

Letter, _, ya $ se start hona chahiye
Space nahi honi chahiye
Java keywords use nahi kar sakte
Case-sensitive: age aur Age alag hain

Naming Conventions (camelCase)

java exampleWoHoTech

int studentAge;    // Good
int student_age;   // Valid but not preferred
int StudentAge;    // Class ke liye use hota hai

title: Variables in Java description: Java mein variables kya hain aur kaise declare karte hain

Variable kya hai?

Variable ek named memory location hai jisme data store hota hai.

Variable Declaration

java exampleWoHoTech

dataType variableName = value;
int age = 25;
String name = "Rahul";
double salary = 50000.50;
boolean isStudent = true;

Variable ke Types

1. Local Variable

Method ke andar declare hota hai
Sirf us method mein accessible
Default value nahi hoti, initialize karna zaruri

java exampleWoHoTech

void myMethod() {
    int x = 10; // local variable
}

2. Instance Variable

Class ke andar, method ke bahar
Har object ka apna copy
Default value milti hai

java exampleWoHoTech

class Student {
    String name;  // instance variable
    int age;
}

3. Static Variable (Class Variable)

static keyword se declare
Sabhi objects share karte hain
Class load hone par create hota hai

java exampleWoHoTech

class Counter {
    static int count = 0;  // static variable
}

Variable Naming Rules

Letter, _, ya $ se start hona chahiye
Space nahi honi chahiye
Java keywords use nahi kar sakte
Case-sensitive: age aur Age alag hain

Naming Conventions (camelCase)

java exampleWoHoTech

int studentAge;    // Good
int student_age;   // Valid but not preferred
int StudentAge;    // Class ke liye use hota hai

Variables in Java

Variable kya hai?

Variable Declaration

Variable ke Types

1. Local Variable

2. Instance Variable

3. Static Variable (Class Variable)

Variable Naming Rules

Naming Conventions (camelCase)

Continue learning this concept

Variables in Java

Variable kya hai?

Variable Declaration

Variable ke Types

1. Local Variable

2. Instance Variable

3. Static Variable (Class Variable)

Variable Naming Rules

Naming Conventions (camelCase)

Continue learning this concept