I first touched Java

I tried to touch Java

Please forgive it as it will be a self-sufficient memorandum.

Display a string

class Hello {
  public static void main(String[] args) {
    System.out.println("hello IKEMEN");
  }
}

↓

Terminal

hello IKEMEN

The character string enclosed in "" is displayed.

Display a string using a variable

class Hello {
  public static void main(String[] args) {
    String name = "IKEMEN"

    System.out.println("hello" + name);
  }
}

↓

Terminal

helloIKEMEN

There is no margin as it is, so I will correct it.

class Hello {
  public static void main(String[] args) {
    String name = "IKEMEN"

    System.out.println("hello " + name);
  }
}

Put a margin after hello in System.out.println ("hello" + name) ;. ↓

Terminal

hello IKEMEN

There is a margin and it is beautiful.

Receive input from users

① Character string

import java.util.Scanner;

class Hello {
  public static void main(String[] args) {
    System.out.print("Your name? ");
    String name = new Scanner(System.in).next();

    System.out.println("hello " + name);
  }
}

It seems that new Scanner (System.in) .next (); can receive input from the keyboard. ↓

Terminal

Your name?

Is displayed, so type in the character string (IKEMEN) ↓

Terminal

Your name? IKEMEN
hello IKEMEN

② Numerical value

import java.util.Scanner;

class Hello {
  public static void main(String[] args) {
    System.out.print("Your guess? ");
    Integer guess = new Scanner(System.in).nextInt();
    
    System.out.println("Your guess: " + guess);
  }
}

It seems that new Scanner (System.in) .nextInt (); receives the input value as an integer. ↓

Terminal

Your guess?

Is displayed, so enter the numerical value (6). ↓

Terminal

Your guess? 6
Your guess: 6

Change the display according to the conditions

import java.util.Scanner;

class Hello {
  public static void main(String[] args) {
    Integer answer = 6;

    System.out.print("Your guess? ");
    Integer guess = new Scanner(System.in).nextInt();
    
    if (answer == guess) {
      System.out.println("Correct answer!");
    } else {
      System.out.print("Lost");
    }
  }
}

If the entered number is 6, it will be displayed as correct! If it is not 6, it will be displayed as lost.

Add a condition

import java.util.Scanner;

class Hello {
  public static void main(String[] args) {
    Integer answer = 6;

    System.out.print("Your guess? ");
    Integer guess = new Scanner(System.in).nextInt();
    
    if (answer == guess) {
      System.out.println("Correct answer!");
    } else if (answer > guess) {
      System.out.println("Larger");
    } else {
      System.out.println("Smaller");
    }
  }
}

If the number you entered is 6, it will be displayed as correct !, if it is less than 6, it will be displayed as larger, and if it is greater than 6, it will be displayed as smaller.