Is lesson me hum seekhenge:
- VarArgs kya hota hai
- VarArgs ka syntax
- VarArgs ka use kyun hota hai
- VarArgs vs Array
- Important rules aur examples
VarArgs ka matlab:
ek method me variable number of arguments pass kar sakte hain
Matlab:
kitne arguments aayenge → fix nahi hai
returnType methodName(dataType... variableName) {
}Example:
void printNumbers(int... numbers) {
}class Test {
static void printNumbers(int... nums){
for(int n : nums){
System.out.println(n);
}
}
public static void main(String[] args){
printNumbers(1);
printNumbers(1, 2, 3);
printNumbers(1, 2, 3, 4, 5);
}
}Java internally VarArgs ko array me convert karta hai.
Example:
void show(int... nums)Internally:
void show(int[] nums)VarArgs ko dusre parameters ke saath bhi use kar sakte hain.
class Test {
static void display(String name, int... marks){
System.out.println(name);
for(int m : marks){
System.out.println(m);
}
}
public static void main(String[] args){
display("Sujit", 90, 85, 80);
}
}✔ VarArgs hamesha last parameter hona chahiye
✔ Ek method me sirf ek VarArgs allowed hai
❌ Invalid:
void test(int... a, int... b) {} // error❌ Invalid:
void test(int... a, int b) {} // error| Feature | VarArgs | Array |
|---|---|---|
| Input | flexible | fixed |
| Syntax | simple | complex |
| Use | multiple arguments | fixed data |
class Test {
static void show(int a){
System.out.println("Single");
}
static void show(int... a){
System.out.println("Multiple");
}
public static void main(String[] args){
show(5); // Single
show(1,2,3); // Multiple
}
}class Calculator {
static int sum(int... numbers){
int total = 0;
for(int n : numbers){
total += n;
}
return total;
}
public static void main(String[] args){
System.out.println(sum(10, 20));
System.out.println(sum(10, 20, 30, 40));
}
}sum(); // allowednums array empty hoga:
length = 0
Use karo jab:
number of inputs fix na ho
Example:
sum(), print(), logger
- VarArgs kya hota hai?
- Kya VarArgs internally array hota hai?
- VarArgs me kitne parameters allowed hote hain?
- VarArgs last me hi kyun hona chahiye?
Is lesson me humne seekha:
✔ VarArgs concept
✔ Syntax aur usage
✔ VarArgs vs array
✔ Rules aur edge cases
VarArgs Java me method ko flexible aur reusable banata hai.