How to Read Input from Console in Java

In this example we will show two ways to read input from console in Java.The first way is relatively simple, requiring you to create a Scanner object with system.in as a parameter.The second way is to wrap system.in using BufferedRead.

Source Code

– Example (1)

package com.beginner.examples;

import java.util.Scanner;

public class ScannerTest {

	public static void main(String[] args) {

		//Create Scanner object
		Scanner scanner = new Scanner(System.in);
		
		while(true) {
			
			System.out.println("Enter the string and exit:");
			
			//Read a line of string
			String line = scanner.nextLine();
			
			if("exit".equals(line.toLowerCase())) {
				System.out.println("Bye");
				break;
			}
			
			System.out.println("Your input is : " + line);
			
		}

	}
	
}

Output:

Enter the string and exit:
I love java
Your input is : I love java
Enter the string and exit:
I love programming
Your input is : I love programming
Enter the string and exit:
exit
Bye

– Example (2)

package com.beginner.examples;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;

public class UseBufferedRead {

	public static void main(String[] args) {

		// Get a byte stream for keyboard entry
		InputStream is = System.in;

		// converts to character stream
		Reader reader = new InputStreamReader(is);

		// wrap Reader as BufferedRead
		BufferedReader br = new BufferedReader(reader);

		// We could also write it this way
		// BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		try {
			System.out.println("Enter the string : ");

			String line = br.readLine();

			System.out.println("Your input is : " + line);
			
			br.close();

		} catch (IOException e) {

			e.printStackTrace();

		}

	}

}

Output:

Enter the string : 
I love programming
Your input is : I love programming

References

Imported packages in Java documentation:

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How to Read Input from Console in Java

In this example we will show 3 ways to read input from a console in Java.

BufferedReader + InputStreamReader (Classic)
Scanner (JDK 1.5)
System.console (JDK 1.6)

Source Code

package com.beginner.examples;
import java.util.Scanner;
public class InputFromConsole1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner scanner = new Scanner(System.in);
        while (true) {
            System.out.println("Please enter content or enter "b" to exit:");
            String strInput = scanner.next();
            if (strInput.equals("b")) {
                scanner.close();
                break;
            } else {
                System.out.println("Your input is:" + strInput);
            }

        }
        System.out.println("over!");
    }

}

Output:

Please enter content or enter "b" to exit:
Hello!
Your input is:Hello!
Please enter content or enter "b" to exit:
b
over!

package com.beginner.examples;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class InputFromConsole2 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        try {
            BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
            System.out.println("Enter content:");
            String str = br.readLine();
            System.out.println("Your input is: " + str);
        } catch (IOException e) {
            // TODO: handle exception
            e.printStackTrace();
        }

    }

}

Output:

Enter content:
Hello!
Your input is: Hello!

Tips

In JDK 1.5, the developer starts to use java.util.Scanner to read system input.
In JDK 1.6, the developer starts to switch to the more simple and powerful java.io.Console class.

References

Imported packages in Java documentation:

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