Why does it run 3 times before asking for user input again?

Question

It works fine with '1'but with the other options it runs 3x times (by printing out the whole Menu thing before allowing user input again.

char a; 
    
    do { 
    System.out.println ("MENU");
    System.out.println ("Press 1 to EXIT");
    System.out.println ("Press 2 to PLAY");
    System.out.println ("Press 3 for SETTINGS");
    a = (char)System.in.read();
    switch (a){
    
    case '1': 
        System.out.println ("You have EXITED");
        break;
    case '2':
        System.out.println ("GAME OVER");
        break;
    case '3':
        System.out.println ("You chose SETTINGS");
        break;
    }
    
    }while (a != '1');




    

Answer 1

By default the console (or similar) is line buffered, so you type a digit followed by return/enter. You are reading a character at a time. The three characters you see are the digit, Carriage Return (CR/'\r') and New Line (NL/'\n').

See this question How to read a single char from the console in Java (as the user types it)? Alternatively read a line at a time - most example programs will use java.util.Scanner.

Answer 2

You have to reset the a as '1'. The reason it was executing repeatedly is because the value of as is not reset