JAVA: Reading input from Keyboard

How does JAVA accepts input from keyboard?
-streams accepts input from keyboard.
-stream is a flow of data.

Types of stream:

• input stream : Receives the data.
• output stream : Writes the data.

Note: 

System.out is used to print the output to the console.

System.in is used to take input from the console.

We can take input from the keyboard in two ways:

1. using InputStreamReader class
2. using Scanner class

PROGRAM EXAMPLE:

1. Using InputStreamReader class

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

public class e_inputStream {

public static void main(String args[]) throws IOException{

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

              // BufferedReader is used to read the data from the input stream

System.out.println("Enter the number:");

int i=Integer.parseInt(br.readLine()); //converting the text to int

System.out.println("the entered number is:"+i);

}

}

Output: 

Enter the number:

10

the entered number is:10

2. Using Scanner class

import java.io.IOException;

import java.util.Scanner;

public class f_scannerclass {

public static void main(String args[]) throws IOException{

Scanner sc=new Scanner(System.in);

//values are stored as a token in scanner object.

System.out.println("Enter the number:");

int i=sc.nextInt();  //to receive the token 

System.out.println("the entered number is:"+i);

}

}

Output:

Enter the number:

10

the entered number is:10

Note: 

print() : keeps the cursor in the same like after displaying the output.

println() : keeps the cursor in the next line after displaying the output.

PREVIOUS