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COMPUTER SOFTWARE APPLICATION - CITS

JAVA Arrays

Normally, an array is a collection of similar type of elements which has contiguous memory location
Java array is an object which contains elements of a similar data type. Additionally, The elements of an array are
stored in a contiguous memory location. It is a data structure where we store similar elements. We can store only
a fixed set of elements in a Java array.Array in Java is index-based, the first element of the array is stored at the
0th index, 2nd element is stored on 1st index and so on.

Unlike C/C++, we can get the length of the array using the length member. In C/C++, we need to use the sizeof
operator.
In Java, array is an object of a dynamically generated class. Java array inherits the Object class, and implements
the Serializable as well as Cloneable interfaces. We can store primitive values or objects in an array in Java. Like
C/C++, we can also create single dimensional or multidimensional arrays in Java. Moreover, Java provides the
feature of anonymous arrays which is not available in C/C++.

Advantages
Code Optimization: It makes the code optimized, we can retrieve or sort the data efficiently.
Random access: We can get any data located at an index position
Disadvantages

Size Limit: We can store only the fixed size of elements in the array. It doesn’t grow its size at runtime. To solve
this problem, collection framework is used in Java which grows automatically.
Types of array:

Single Dimensional Array
Multidimensional Array
Syntax to Declare an Array in Java
dataType[] arr; (or)
dataType []arr; (or)
dataType arr[];
Instantiation of an Array in Java
arrayRefVar=new datatype[size];
Example of Java Array
Let’s see the simple example of java array, where we are going to declare, instantiate, initialize and traverse an
array.
Java Program to illustrate how to declare, instantiate, initialize
and traverse the Java array.
class Testarray{
public static void main(String args[]){
int a[]=new int[5];//declaration and instantiation
a[0]=10;//initialization
a[1]=20;
a[2]=70;

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CITS : IT&ITES - Computer Software Application - Lesson 85 - 93