Java user Input-10 Programs
How to get input from user in Java and there different types of input.
Java Scanner Class
Java Scanner class allows the user to take input from the console. It belongs to java.util package. It is used to read the input of primitive types like int, double, long, short, float, and byte. It is the easiest way to read input in Java program.
Syntax
1. Scanner sc=new Scanner(System.in);
Following fig.no.1.chart more useful for taking input at that particular type. So don’t worry about chart right now , I will explain one by one.
PROGRAM :1:
Example of integer input from user
The following example allows user to read an integer form the System .in .So we use
CODE:
import java.util.*;
class Print_Integer
{
public static void main(String[] args)
{
Scanner sc= new Scanner(System.in); //System.in is a standard input stream
System.out.print(“Enter integer number :”);
String a= sc.nextLine(); //taking input from user same as scanf in c
System.out.println(“OUTPUT :”+a);
}
}
OUTPUT:
Enter integer number :5
OUTPUT :5
PROGRAM 2:
Example of String Input from user
Let’s see another example, in which we have taken string input.using sc.nextLine() function.
CODE:
import java.util.*;
class UserInputDemo1
{
public static void main(String[] args)
{
Scanner sc= new Scanner(System.in); //System.in is a standard input stream
System.out.print(“Enter a string: “);
String str= sc.nextLine(); //reads string
System.out.print(“You have entered: “+str);
}
}
OUTPUT:
Enter a string: somnath
You have entered: somnath
Program 3:Example of Taking float number
CODE:
import java.util.Scanner;
class floatexample
{
public static void main(String[] args)
{
Scanner sc= new Scanner(System.in); //System.in is a standard input stream
System.out.print(“Enter a float: “);
float flt= sc.nextFloat(); //reads string
System.out.print(“You have entered: “+flt);
}
}
OUTPUT:
Enter a float: 5.6
You have entered: 5.6
Program 4:Example of Taking Double number
This program is simlar to previous one only difference is that we have taken input as double and function are used nextDouble().
CODE:
import java.util.Scanner;
class doubleexample
{
public static void main(String[] args)
{
Scanner sc= new Scanner(System.in); //System.in is a standard input stream
System.out.print(“Enter a double: “);
double dbl= sc.nextDouble(); //reads string
System.out.print(“You have entered: “+dbl);
}
}
OUTPUT:
Enter a double: 1.99988
You have entered: 1.99988
Program 5:
CODE:
import java.util.Scanner;
class booleanexample
{
public static void main(String[] args)
{
Scanner sc= new Scanner(System.in); //System.in is a standard input stream
System.out.print(“Enter a Boolean: “);
boolean bl= sc.nextBoolean(); //reads string
System.out.print(“You have entered: “+bl);
}
}
OUTPUT:
Enter a Boolean: false
You have entered: false
This is 5 program about taking input of a different type.
Now we will do some operation on that we have taken different type of input.
Program 6:Addition of two integer using nextint()
Expln:This program addition of 3 integer numbers usig nextint()
CODE:
import java.util.*;
class UserInputthreeadd
{
public static void main(String[] args)
{
Scanner sc= new Scanner(System.in); //System.in is a standard input stream
System.out.print(“Enter first number- “);
int a= sc.nextInt();
System.out.print(“Enter second number- “);
int b= sc.nextInt();
System.out.print(“Enter third number- “);
int c= sc.nextInt();
int d=a+b+c;
System.out.println(“Total= “ +d);
}
}
OUTPUT:
Enter first number- 5
Enter second number- 6
Enter third number- 8
Total= 19
Program 7:Multiplication of two integer using nextint()
Expln:This program of a multiplication of 2 integer numbers usig nextint()
This program is similar to previous one only we are taking two integers and mutilpying.
CODE:
import java.util.*;
class MultiplicationUserInputDemo
{
public static void main(String[] args)
{
Scanner sc= new Scanner(System.in); //System.in is a standard input stream
System.out.print(“Enter first number- “);
int a= sc.nextInt();
System.out.print(“Enter second number- “);
int b= sc.nextInt();
int d=a+b;
System.out.println(“Multiplication of two numbers = “ +d);
}
}
OUTPUT:
Enter first number- 5
Enter second number- 6
Multiplication of two numbers = 30
*This way you can perform Multiplication,Subtraction and division and other.
Program 8:merging of two string using + and taking input through nextline()
CODE:
import java.util.*;
class Mergingstring
{
public static void main(String[] args)
{
Scanner sc= new Scanner(System.in); //System.in is a standard input stream
System.out.print(“Enter a string a: “);
String a= sc.nextLine();
System.out.print(“Enter a string b: “);
String b= sc.nextLine(); //reads string
String c=a+” “+b;
System.out.print(“You’r merging result of string: “+c);
}
}
OUTPUT:
Enter a string a: Harshad
Enter a string b: Mehta
You’r merging result of string: Harshad Mehta
Program 9:Printing table using for loop and input taking through nextint().
CODE:
import java.util.*;
class printuptofive
{
public static void main(String[] args)
{
Scanner sc= new Scanner(System.in); //System.in is a standard input stream
System.out.print(“Enter number to yo want print table:”);
int n= sc.nextInt(); //reads string
for(int i=1;i<10;i++) {
System.out.print(n*i); //multiplay one by one
System.out.print(“\n”);//for newline
}
}
}
OUTPUT:
Enter number to yo want print table:10
10
20
30
40
50
60
70
80
90
100
Program 10:Taking array as input and printing array using for loop.
CODE:
import java.util.Scanner;
public class ArrayInputExample1
{
public static void main(String[] args)
{
int n;
Scanner sc=new Scanner(System.in);
System.out.print(“Enter the number of elements you want to store: “);
//reading the number of elements from the that we want to enter
n=sc.nextInt();
//creates an array in the memory of length 10
int[] array = new int[10];
System.out.println(“Enter the elements of the array: “);
for(int i=0; i<n; i++)
{
//reading array elements from the user
array[i]=sc.nextInt();
}
System.out.println(“Array elements are: “);
// accessing array elements using the for loop
for (int i=0; i<n; i++)
{
System.out.println(array[i]);
}
}
}
OUTPUT:
Enter the number of elements you want to store: 5
Enter the elements of the array:
1
2
3
4
5
Array elements are:
1
2
3
4
5
Thank you.