Easy Tutorial
For Competitive Exams
Aptitude
TNPSC G4
10th CBSE Maths
  1. Home
  2. Java Programming

Java Programming Scanner

What is Scanner class?

Scanner is a class used for obtaining the input of the primitive types like int, double etc. and strings.

To use the Scanner class, we first need to include java.util package in our program.

We include a package in a program with the help of import keyword. We can either import the java.util.Scanner class or the entire java.util package.

To import a class or a package, add one of the following lines to the very beginning of your code.

Example:

import java.util.Scanner;   // This will import just the Scanner class
import java.util.*;   // This will import the entire java.util package

After importing, we need to write the following statement in our program.

Example:

Scanner s = new Scanner (System.in);

Here by writing Scanner s, we are declaring s as an object of Scanner class.

System.in within the round brackets tells Java that this will be System Input i.e. input will be given to the system.

Methods in Scanner Class:

Method Inputs
nextInt() Integer
nextFloat() Float
nextDouble() Double
nextLong() Long
nextShort() Short
next() Single word
nextLine() Line of Strings
nextBoolean() Boolean

How to input a Integer value?

we will input an integer value from the user using nextInt() method.

Example:

import java.util.Scanner;
class IntegerDemo{
  public static void main(String[] args){
    Scanner s1 = new Scanner(System.in);
    System.out.println("Enter an integer");
    int a;
    a = s1.nextInt();
    System.out.println("The entered integer is" + a);
  }
}

Output:

Enter an integer
14
The entered integer is14

How to input a word?

we will input an word from the user using next() method.

Example:

import java.util.*;
class WordDemo{
  public static void main(String[] args){
    Scanner s1 = new Scanner(System.in);
    System.out.println("Enter your first name");
    String f = s1.next();
    System.out.println("Enter your last name");
    String l = s1.next();
    System.out.println("Your name is " + f + l);
  }
}

Output:

Enter your first name
Robert
Enter your last name
Jhon
Your name is RobertJhon

How to input a line or Sentence?

we will input a line or sentence from the user using nextLine() method.

Example:

import java.util.*;
class SentenceDemo{
  public static void main(String[] args){
    Scanner s1 = new Scanner(System.in);
    System.out.println("Enter your name");
    String name = s1.nextLine();
    System.out.println("Your name is " + name);
  }
}

Output:

Enter your name
Robert Jhon
Your name is Robert Jhon

The only difference between the methods nextLine() and next() is that nextLine() reads the entire line including white spaces, whereas next() reads only upto the first white space and then stops.

Example:

import java.util.*;
class DifferenceDemo{
  public static void main(String[] args){
    Scanner s1 = new Scanner(System.in);
    System.out.println("Enter your name");
    String w = s1.next();
    System.out.println("Your name is " + w);
    System.out.println("Again enter your name");
    String st = s1.nextLine();
    System.out.println("Your name is " + st);
  }
}

Output:

Enter your name
Robert Brown Jr.
Your name is Robert 
Again enter your name 
Your name is Brown Jr.

Here, next took only the first word. Rest of the words were taken by nextLine.

How to input different datatypes?

Above table shows different methods to get the input like integer,double float,string.etc.,

Example:

import java.util.*;
class DifferentDataDemo{
  public static void main(String[] args){
    Scanner s1 = new Scanner(System.in);
    System.out.println("Enter integer");
    int n = s1.nextInt();
    
    System.out.println("Enter double");
    double db = s1.nextDouble();
   
    System.out.println("Integer :" + n);
    System.out.println("Double :" + db);
  }
}

Output:

Enter integer
45
Enter double
23.242
Integer :45
Double :23.242

Solve this!!

42401.Which package should be imported to use Scanner class?
import java.util.System.in;
import java.util.Scanner;
import java.util.System;
import java.util.Input;
42402.Which method does not store string value after space?
next()
nextString()
nextLine()
Both 1 and 3
42403.Which is the correct syntax to declare Scanner class object?
Scanner objectName= Scanner();
Scanner objectName= new Scanner();
Scanner objectName= Scanner(System.in);
Scanner objectName= new Scanner(System.in);
42404.Which Scanner class method is used to read integer value from the user?
next()
nextInteger()
nextInt()
readInt()
Share with Friends