1.9 Arrays in Java.

Array : Array can hold only homogeneous data elements.

Example :

student[] s = new student[100];

s[0] = new student(); //correct

s[1] = ne customer(); //wrong

-> but we can resolve this proble using object array.

object[] o = new object[100];

o[0] = new student(); //correct

o[1] = new customer(); //correct

1. Array are fixed in soze.

2. Array are hold homogeneous datatype.

3. underlying data structure not accepted.

10

25

46

-----

89

    0                1               2                            n-1    

array size : n elements

index range : 0 to n-1

arrayNmae[2] : 3rd element

Array Declaration: 

int[] arr1; //array of int type.

float[] array1; //array of float type.

char[] array1; //array of char type.

ArrayNmae = new arrayType[size];

arr1 = new int[5];

arr2 = new float[10];

arr3 = new char[20];

int arr1;

arr1 = new int[5];

25

40

56

98

120

        0            1                2               2            3

Strore Varues :

arr1[0] = 25;

arr1[1] = 40;

arr1[2] = 56;

arr1[3] = 98;

arr1[4] = 120;

System.out.println(arr1[3]);

for(int i =0 ; i<5; i++)

{

System.out.println(arr1[i])

}

Example Program1 :

class Program1

{

public static void main(String args[])

{

System.out.println("progrm started");

int arr1; //declaration

arr1 = new int[5]; //initialization

//Store Values.

arr1[0] = 25;

arr1[1] = 40;

arr1[2] = 56;

arr1[3] = 98;

arr1[4] = 120;

System.out.println("4th element"+arr1[3]);

System.out.println("Array elements");

for(int i =0 ; i<5; i++)

{

System.out.println(arr1[i])

}

}

}

for more details follow video given below.