Check out example codes for "how to read input in java". It will help you in understanding the concepts better.

Code Example 1

import java.util.Scanner;  // Import the Scanner class

class MyClass {
  public static void main(String[] args) {
    Scanner myObj = new Scanner(System.in);  // Create a Scanner object
    System.out.println("Enter username");

    String userName = myObj.nextLine();  // Read user input
    System.out.println("Username is: " + userName);  // Output user input
  }
}

Code Example 2

String str = System.console().readLine();

Code Example 3

//For continues reading a line
import java.util.Scanner; 

Scanner in = new Scanner(System.in); 
while(in.hasNextLine()) {
   String line = in.nextLine();
   System.out.println("Next line is is: " + line); 
}

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