Array in java programming

Array in java programming

Array is a collection of data element in a cell ,every elements are storing under the same name is done using
an array.An array can hold any type of data in a cell .data elements accessing elements of array by index.

Declaring one dimension array in java

type var-name[];

For example :
int[] Dev ;
or , you can also declare it as follows :
int Dev[];
If an array is declared as : int Dev[3], it means it has 4 element from Dev[0] to Dev[3].
Allocating memory to arrays :
var-name = new type[size];
Example :
Dev = new int[12];
Assigning and accessing value from array
You can assign value directly, like this :
Dev[0] = 12; // this will assign value to first element.
Dev[1] = 30 // this will assign value to second element.
Array can also be assigned when they are declared as :
int Dev[] = {3, 12, 21, 30, 39, 48};
You can access array element like this :
System.out.println(Dev[3]); // This will print 4th element of array.
Example an array
public class DevArray {
public static void main(String[] args) {
double[] devList = {1.9, 2.9, 3.4, 3.5};
// Print all the array elements
for (double element: devList) {
System.out.println(element);
}
}
}

Multidimensional array :

In java, multidimensional arrays are actually arrays of arrays. For example, you can declare a two dimensional array as :
int twoD[][]=new int [4][5];
You can also declare a three dimensional array as :
int threeD[][][]= new int [3][4][5];
If an array is declared as : int Dev[3], it means it has 4 element from Dev[0] to Dev[3].
Allocating memory to arrays :
var-name = new type[size];
Example :
Dev = new int[12];

Class TwoDmatrix{
public static void main(String args[]) {
int twoDm[][]= new int[4][5];
int i,j,k=0;
for(i=0;i<4;i++)
for(j=0;j<5;j++) {
twoDm[i][j]=k;
k++;
}
for(i=0;i<4;i++)
for(j=0;j<5;j++) {
System.out.println(twoDm[i][j]+"")
System.out.println();
}
}
}