Scanner class in java

In previous post , we have see Console class in java. In this post, we will see usage of Scanner class.

In java, Scanner class is used to read the input from keyboard. Even though, there are numerous ways to read the keyboard input, Scanner is one of them.

The Java Scanner class breaks the input into tokens using a delimiter that is whitespace bydefault. It provides many methods to read and parse various primitive values.The resulting tokens may then be converted into values of different types using the various next methods

It can parse primitive types and strings using regular expressions.It implements Iterator and closeable Interfaces.

Few Constructors Of scanner class: 

1. Scanner(File source): Constructs a new Scanner that produces values scanned from the specified file.
2. Scanner(File source, String charsetName): Constructs a new Scanner that produces values scanned from the specified file.
3. Scanner(InputStream source): Constructs a new Scanner that produces values scanned from the specified input stream.
4. Scanner(InputStream source, String charsetName): Constructs a new Scanner that produces values scanned from the specified input stream.
5. Scanner(String source): Constructs a new Scanner that produces values scanned from the specified string.

Commonly used methods of Scanner class:

Example of Scanner class:

public class SacnnerEx {
	public static void main(String[] args){	
		  Scanner sc=new Scanner(System.in);  
		     
		   System.out.println("Enter your Empid");  
		   int rollno=sc.nextInt();  
		   System.out.println("Enter your name");  
		   String name=sc.next();  
		   System.out.println("Enter your Salary");  
		   double fee=sc.nextDouble();  
		   System.out.println("EmpID:"+rollno+" name:"+name+" Salary:"+fee);  
		   sc.close();  
		 }
}