Taking User Input in Java
So far we were working on pre-initialized data. But real life application also requires different inputs from the application user.
In order
to take user input, we use Scanner class
in Java.
But,
before using Scanner class, we need to include java.util package. java.util
package contains the Scanner class with all its required methods to be used
while writing program for taking user
input.
First,
you need to create an object of the Scanner
class.
After
that you can use all the methods
available inside the Scanner class to take different form of user input.
Scanner Class Methods in Java (Input
Types):
|
Methods |
Uses of the Method |
|
nextLine() |
This method is used to read a String value |
|
nextChar() |
This method is used to read a Character value |
|
nextBoolean() |
This method is used to read a Boolean value |
|
nextInt() |
This method is used to read a Integer value |
|
nextShort() |
This method is used to read a Short value |
|
nextLong() |
This method is used to read a Long value |
|
nextFloat() |
This method is used to read a Float value |
|
nextDouble() |
This method is used to read a Double value |
Example of User Input:
1) Simple Interest Calculation
package userInput;
import java.util.Scanner;
public class ScannerUserInput {
public static void main(String[] args) {
Scanner
sc = new Scanner(System.in);
System.out.println("Enter the
principal amount:");
int principal = sc.nextInt();
System.out.println("Enter the
rate of interest:");
float rate = sc.nextFloat();
System.out.println("No. of
Years:");
int time = sc.nextInt();
float simpleInterest = principal * rate * time / 100;
System.out.println("The simple
interest is "+simpleInterest);
}
}
Output:
Enter the principal amount:
10000
Enter the rate of interest:
10
No. of Years:
1
The simple interest is 1000.0
2) User Input - String Value:
package userInput;
import java.util.Scanner;
public class ScannerUserInput {
public static void main(String[] args) {
Scanner
sc = new Scanner(System.in);
// int
principal = sc.nextInt();
System.out.println("Enter your
first name:");
String
firstname = sc.nextLine();
System.out.println("Enter your
last name:");
String
lastname = sc.nextLine();
System.out.println("Your full
name is "+firstname+" "+lastname);
}
}
Output:
Enter your first name:
Rima
Enter your last name:
Saha
Your full name is
Rima Saha
3) Simple Billing Application for Ration
Shop:
package userInput;
import java.util.Scanner;
public class ScannerUserInput {
public static void main(String[] args) {
Scanner
sc = new Scanner(System.in);
// Heading
System.out.println("===================");
System.out.println("E-Ration Shop
Billing");
System.out.println("===================");
System.out.println(" ");
// Ration
Rate List
int ricerate = 10;
int sugarrate = 15;
int koilrate = 7;
// User
Input
System.out.println("Rice
(KG):");
int rice = sc.nextInt();
System.out.println("Sugar
(KG):");
int sugar = sc.nextInt();
System.out.println("Kerosene Oil
(lt.):");
int koil = sc.nextInt();
// Total
price calculation
int ricecost = ricerate * rice;
int sugarcost = sugarrate * sugar;
int koilcost = koilrate * koil;
int total = ricecost + sugarcost + koilcost;
System.out.println(" ");
System.out.println("===================");
// Billing
System.out.println("Print
Bill");
System.out.println("===================");
System.out.println(" ");
System.out.println("Rice .....
("+rice+" kg x Rs.10/kg)
= Rs."+ricecost+"/-");
System.out.println("Sugar .....
("+sugar+" kg x
Rs.15/kg) = Rs."+sugarcost+"/-");
System.out.println("Kerosene Oil
..... ("+koil+" lt x Rs.7/lt.) = Rs."+koilcost+"/-");
System.out.println(" ");
System.out.println("===================");
System.out.println("Total billing
amount is Rs."+total+"/-");
System.out.println("===================");
System.out.println(" ");
System.out.println(" ");
System.out.println("THANK
YOU");
System.out.println("E-RATION
SHOP");
}
}
Output:
===================
E-Ration Shop Billing
===================
Rice (KG):
35
Sugar (KG):
10
Kerosene Oil (lt.):
8
===================
Print Bill
===================
Rice ..... (35 kg x Rs.10/kg) =
Rs.350/-
Sugar ..... (10 kg x Rs.15/kg) =
Rs.150/-
Kerosene Oil ..... (8 lt x Rs.7/lt.) =
Rs.56/-
===================
Total billing amount is Rs.556/-
===================
THANK YOU
E-RATION SHOP
No comments: