Scanner is a class in java.util package used for obtaining the input of the primitive types like int, double, etc. and strings. It is the easiest way to read input in a Java program, 

• To create an object of Scanner class, we usually pass the predefined object System.in, which represents the standard input stream. We may pass an object of class File if we want to read input from a file.
• To read numerical values of a certain data type XYZ, the function to use is nextXYZ(). For example, to read a value of type short, we can use nextShort()
• To read strings, we use nextLine().
• To read a single character, we use next().charAt(0). next() function returns the next token/word in the input as a string and charAt(0) function returns the first character in that string.

// Java program to read data of various types using Scanner class. 
import java.util.Scanner; 
public class ScannerDemo1 
{ 
    public static void main(String[] args) 
    { 
        // Declare the object and initialize with 
        // predefined standard input object 
        Scanner sc = new Scanner(System.in); 
  
        // String input 
        String name = sc.nextLine(); 
  
        // Character input 
        char gender = sc.next().charAt(0); 
  
        // Numerical data input 
        // byte, short and float can be read 
        // using similar-named functions. 
        int age = sc.nextInt(); 
        long mobileNo = sc.nextLong(); 
        double cgpa = sc.nextDouble(); 
  
        // Print the values to check if the input was correctly obtained. 
        System.out.println("Name: "+name); 
        System.out.println("Gender: "+gender); 
        System.out.println("Age: "+age); 
        System.out.println("Mobile Number: "+mobileNo); 
        System.out.println("CGPA: "+cgpa); 
    } 
} 
Input :

Geek
F
40
9876543210
9.9
Output :

Name: Geek
Gender: F
Age: 40
Mobile Number: 9876543210
CGPA: 9.9