Data input methods in java: There are many data input methods in java like Hard coded values, through main method, with Scanner class, with Buffered Reader
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Hard Coded Values:-
The values are stored in a variable and used later.
public class AddTwoNumbers
{
public static void main()
{
int num1 = 5, num2 = 15, sum;
sum = num1 + num2;
System.out.println("Sum of numbers: "+sum);
}
}
This method is easy and simple but it gives same output every time
Taking values through main method
Pubic static void main(int a, int b)
{
int sum=a+b;
System.out.println(“The sum is”+sum);
}
This method is easy, simple, different values can be passed for each execution according the input. It will give different output
Scanner class:-
The scanner class is in util package so this statement is compulsory if you want to take input through scanner class.
import java.util.*; Make an object of the class Scanner.
Scanner sc=new Scanner(System.in); It is used to take input through the keyboard using different methods according the data type.
The Scanner class methods are as follows.
boolean nextBoolean() | To read a boolean value from the user |
byte nextByte() | To read a byte value from the user |
double nextDouble() | To read a double value from the user |
float nextFloat() | To read a float value from the user |
int nextInt() | To read an int value from the user |
String nextLine() | To read a String value from the user |
long nextLong() | To read a long value from the user |
short nextShort() | To read a short value from the user |
Advantages Data is input at run time. Gives output according the input
import java.util.Scanner;
public class AddTwoNumbers2
{
public static void main(String[] args)
{
int num1, num2, sum;
Scanner sc = new Scanner(System.in);
System.out.println("Enter First Number: ");
num1 = sc.nextInt();
System.out.println("Enter Second Number: "); num2 = sc.nextint();
sum = num1 + num2;
System.out.println("Sum of these numbers: +sum);
}
}
Output:
Enter First Number: 121
Enter Second Number: 19
Buffered Reader :
Buffered Reader class is used to take input in java. It has only one method to take input from the user at run time. It is in java.io package. The object of the class is created with this syntax.
BufferedReader br=new BufferedReader(new InputStreamReader(System.in))
The input is taken in string form only.
Write a program to add two numbers (taking input with BufferedReader)
import java.io.*;
class Addition {
public static void main() throws Exception
{
int a, b, c;
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter the two numbers to add:");
a = int.parseint(br.readLine());
b = int.parseint(br.readLine());
c = a + b;
System.out.println("\n Sum of two numbers:" + c);
}
}
Output:
Enter the two numbers to add :2.3 3.5
Sum of two numbers: 5.8