Arrays In Java

Question: What is Array in Java ?

Ans: java me Array ek Non primitive data type ek data structure hota hai jo multiple variable ko ek sath store krne me help karta hai .

Syntax of Array

Syntax of Array - - - -

type [] arryName = new type[size];

1) type=  Type ka mtlb hame jis type ka array chahiye jaise int,float, double 
2) [ ] = ye square bracket jaha v honge java me iska mtlb hai we are creating a array

3) arrayName = arrayName just like a variable name 

4) new = new ek keyword hai, new ka use ham krte hai ek non primite data type ke liye memory me space allocate krne ke liye.

Example: 

int [ ] studentMarks = new int[3];

Isme Index 0 se hota hai isliye ham 0 se likh rhe

package HelloWorld;

import java.util.Scanner; //this is a Scanner class

public class LearningJava {

public static void main (String [] args) {

int [ ] Marks = new int[3];

Marks [0] = 93;

Marks [1] = 10;

Marks [2] = 12;

System.out.print(Marks);

}

}

Output: [I@1ddc4ec2 

Yaha jab aap print karoge to ek jargon print hoga jo ki class and array ka mixture hoga dssd

agr actual data print krna hai to ham [] bracket ke sath print krenge 

package HelloWorld;

import java.util.Scanner; //this is a Scanner class

public class LearningJava {

public static void main (String [] args) {

int [ ] Marks = new int[3];

Marks [0] = 93;

Marks [1] = 10;

Marks [2] = 12;

System.out.print(Marks[1]);

}

}

Kuch is trh to print me 1 st index me jo value hogi wo print ho jayegi

10

Output ye rhega


How to get input array from user 

package HelloWorld;

import java.util.Scanner; //this is a Scanner class

public class LearningJava {

public static void main (String [] args) {

// how to get input array from user

Scanner scan = new Scanner (System.in); // this is scanner class for take input

int size = scan.nextInt(); //take input fro size from user

// hamne user se integer input size le liya

int [] numBer = new int[size]; // usi size ke liye hamne ek array bna diya

for(int i = 0 ;i<=size;i++) { //hamne ek loop banaya hai jo 0 index se start krke size jitni user dega tb tk chlayenge

// this is for output System.out.println(numBer[i]);

}

}

}

• Agar ham kisi bhi array ki value assign nhi krte hai to uski default value hi print hoti hai 
• int ki default value 0 hoti hai 
• char ki default value false
• isi trh double and float ki 0.0 default value hoti hai 
  
  
  
  
Question: how i can take input from user in Array ?
Ans: 

package aRray;

import java.util.*;

public class myArray {

public static void main(String[] args) {

Scanner scan = new Scanner(System.in);

int size = scan.nextInt(); ///Size for array

int [] aRray = new int[size];

/* 1) yaha ham int ka array bana rhe

2) array me ham [] square bracket laga rhe it will represent that this is array

3) array ka variable name aRray rkha hai , int type ka array banaya hai jiska

name hamne aRray rha hai , ise ham declaration of array kehenge

4) memory allocation karenge new int ke name se jisme new memory hai aur memory space type

int hai

5) size hamne user se liya hai isliye us variable ka name hamne yaha identifier bna diya hai*/

for(int i = 0; i < size ; i++) {

/* 6) yaha ham ek loop le rhe for loop jise ham zero se initialize kr rhe, kyo ki index value zero hoti hai*/

aRray[i] = scan.nextInt();

} for(int i = 0 ; i < size; i++) {

/* is loop se ham aRray[i] me store kiye gaye values ko ek ek karke print kr rhe */

System.out.println(aRray[i]);

}

}

}

This is way to take input

Note: In Array there is no any pre defined functions or methods nhi hota hai jisse kisi bhi array ko direct remove kiya ja sake .