
Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Different Ways to Iterate Over an Array in Java
In general, arrays are the containers that store multiple variables of the same datatype. These are of fixed size and the size is determined at the time of creation. Each element in an array is positioned by a number starting from 0.
You can access the elements of an array using name and position as −
System.out.println(myArray[3]); //Which is 1457
Creating an array in Java
In Java, arrays are treated as referenced types you can create an array using the new keyword similar to objects and populate it using the indices as −
int myArray[] = new int[7]; myArray[0] = 1254; myArray[1] = 1458; myArray[2] = 5687; myArray[3] = 1457; myArray[4] = 4554; myArray[5] = 5445; myArray[6] = 7524;
Or, you can directly assign values with in flower braces separating them with commas (,) as −
int myArray = { 1254, 1458, 5687, 1457, 4554, 5445, 7524};
Iterating over an array
You can iterate over an array using for loop or forEach loop.
Using the for loop − Instead on printing element by element, you can iterate the index using for loop starting from 0 to length of the array (ArrayName.length) and access elements at each index.
Example
public class IteratingArray { public static void main(String args[]) { //Creating an array int myArray[] = new int[7]; //Populating the array myArray[0] = 1254; myArray[1] = 1458; myArray[2] = 5687; myArray[3] = 1457; myArray[4] = 4554; myArray[5] = 5445; myArray[6] = 7524; //Printing Contents using for loop System.out.println("Contents of the array: "); for(int i=0; i<myArray.length; i++) { System.out.println(myArray[i]); } } }
Output
Contents of the array: 1254 1458 5687 1457 4554 5445 7524
Using the for each loop − Since JDK 1.5, Java introduced a new for loop known as foreach loop or enhanced for loop, which enables you to traverse the complete array sequentially without using an index variable.
You can iterate the contents of an array with less effort using this.
Example
import java.util.Arrays; public class IteratingArray { public static void main(String args[]) { //Creating an array int myArray[] = new int[7]; //Populating the array myArray[0] = 1254; myArray[1] = 1458; myArray[2] = 5687; myArray[3] = 1457; myArray[4] = 4554; myArray[5] = 5445; myArray[6] = 7524; //Printing Contents using for each loop System.out.println("Contents of the array: "); for (int element: myArray) { System.out.println(element); } } }
Output
Contents of the array: [1254, 1458, 5687, 1457, 4554, 5445, 7524]