Quick introduction to Java Programming language - Part 1

Java supports data structure the array is used to stored fixed size collection of elements of same type. For Example if we need to store number from 1 to 10 instead of declaring individual variable we can declare one array variable having number from 1 to 10.

Declaring Array Variables:

To use an array in a program variable should be declared to reference the array and type of array should be mentioned.

dataType[] RefVararray;
double[] SalaryList;

Creating Arrays: 

Array can be created by using new keyword. 

RefVararray = new dataType[arraySize];

The above declaration does below things:

1. Creates array using new dataType[arraySize];
2. It assigns reference of newly created array to variable RefVararray.

int[] myUserList = new int[10];

The above statement creates an integer array myUserList with array of 10 elements. The index of the 10 elements will be from 0 to 9.

The Arrays Class:

The java.util.Arrays class contains few static methods for searching and sorting arrays, filling array and comparing arrays. These methods can be overloaded for all primitive types.

Processing Arrays:

For processing array elements for or foreach loop is used since all elements in the array are of same size and type.

public class ExampleArray {
    public static void main(String[] args) {
		int[] numList = {5,9,8,7};  
		for (inti = 0; i<numList.length; i++) {
			System.out.println(numList[i] + " ");
		}      
	}
}