Arrays in java..............?

 Arrays:

In Java arrays are dynamically allocated. All array indexes starts from 0. Java has run time array boundary check.

One Dimensional Array:

In Java Arrays are declared in two steps:

a. Declare a array.

 Syntax:

 type variableName[]; e.g. int rollNos[];

b. Allocate memory for the array.

 Syntax: 

variableName = new type[size];

e.g. rollNos = new int[30];

Above two steps can be combined in one step as:

e.g. int rollNos[] = new int[30];

Initializing array:

Syntax: 

variableName[index] = value; e.g. rollNos[0] = 1;

Arrays can be initialized when they are declared as:

Syntax: 

type variableName[] = {initializer list};

e.g. int rollNos[] = {1,2,3,4,5};

Multi Dimensional Array:

Multidimensional arrays are actually arrays of arrays

e,g, int twoD[][] = new int[2][3];

e.g. int twoD[][] = { {2,3,4,5}, {2,2,1,4}, {3,2,4,5} };