JAVA USER INPUT

Java allow user's to give input for a java program and expect the output accordingly. In this module we will learn how to take the input from user in java using the object of Scanner class. There are many ways to take the input from user, that we will learn later.

Table of Contents

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  • How to get the User Input in Java ?
  • Java Scanner Class methods

How to get the User Input in Java ?

In our previous tutorial we have learnt how to take the input from command line. If not then kindly have a look at Java Command Line Arguments. Now we will learn about taking the user input using object of Scanner class.

Scanner class lies within java.util package that means we have to import java.util package before we can use the object of Scanner class.

import java.util.Scanner;

It is used to read input of Primitive data types (int, char, byte, float, double, long) in Java. Below is the syntax for creating object of Scanner class.

Syntax

Scanner sc=new Scanner(System.in);

Example 1

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// Java program to read an integer using System.in
import java.util.*;
public class ReadInputExample{
     public static void main(String args[]){  
         Scanner sc= new Scanner(System.in); // object of Scanner class created
         System.out.print("Enter your age ");
         int age = sc.nextInt();  // it will read user input
         System.out.println("Your age is : " + age);
    }
}

OUTPUT

Enter your age 22Your age is : 22

Example 2

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// Java program to read an integer using System.in
import java.util.*;
public class ReadInputExample{
     public static void main(String args[]){  
         Scanner sc= new Scanner(System.in); // object of Scanner class created
         System.out.print("Enter your College name ");
         String name= sc.nextLine();  // it will read user input
         System.out.println("Your College name is : " + name);
    }
}

OUTPUT

Enter your College name: IIT KanpurYour College name is : IIT Kanpur

In the above examples given we have used nextInt() and nextLine() methods to read integer and string. You can also read other types using the given table below under section Java Scanner Class methods. Give a try yourself.

Java Scanner Class methods

There are various methods provided by Java Scanner class to read different Primitive data types.

MethodsShort Description
nextInt()It is used to read the int value provided by the user
nextByte()It is used to read the byte value provided by the user
nextFloat()It is used to read the float value provided by the user
nextShort()It is used to read the short value provided by the user
nextLong()It is used to read the long value provided by the user
nextDouble()It is used to read the double value provided by the user
nextLine()It is used to read the String value provided by the user
nextBoolean()It is used to read the boolean value provided by the user

In this module we have learnt how to get the User Input in Java and Java Scanner Class methods. This was the last module of Java Basics.

Now we will learn about Java Control Statements in the next tutorial.