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Java Java Basics Perfecting the Prototype Censoring Words - Looping Until the Value Passes

Can someone please explain me what do, while are and do in java

import java.io.Console;

public class TreeStory {

    public static void main(String[] args) {
        Console console = System.console();
        /*  Some terms:
            noun - Person, place or thing
            verb - An action
            adjective - A description used to modify or describe a noun
            Enter your amazing code here!
        */
      //__Name__ is a __adjective__ __noun__. They are always __adverb__ __verb__.
      String ageAsString = console.readLine("How old are you?  ");
      int age = Integer.parseInt(ageAsString);
      if(age<13){
        console.printf("Sorry you must be at least 13 to use this program.\n");
        System.exit(0);
      }
      String name = console.readLine("Enter a name:  ");  
      String adjective = console.readLine("Enter an adjective:  ");
      String noun;
      do {
        noun = console.readLine("Enter a noun: ");
        if (noun.equalsIgnoreCase("dork") || 
            noun.equalsIgnoreCase("jerk")) {
        console.printf("That language is not allowed. Try again.\n\n");
        }
      } while(noun.equalsIgnoreCase("dork") || noun.equalsIgnoreCase("jerk"));                          
      String adverb = console.readLine("Enter an adjective:  ");
      String verb = console.readLine("Enter a verb ending with -ing:  ");

      console.printf("Your TreeStory.\n----------------------------\n");
      console.printf("%s is a/an very %s %s.  ", name, adjective, noun);
      console.printf("They are always %s %s.\n", adverb, verb);
    }

  }

Moderator Edit: Corrected Markdown so code displays properly. (Needed to be Backticks, not Single Quotes to open block.

2 Answers

Alexander Lebedev
Alexander Lebedev
5,875 Points

DO WHILE operator runs piece of code firstly and then checks the condition.

public class Example1 { public static void main (String [] args){ int i = 0; while (i < 10){ System.out.print (i++); } } } // The output will be 0123456789.

public class Example2 { public static void main (String [] args ){ int i = 0; do{ System.out.print (++i); } while (i < 10); } } // The output will be 12345678910.

Jakub ลฤ…tkiewicz
Jakub ลฤ…tkiewicz
5,181 Points

The do while loop is very similar to the while loop. The only difference is that it's guaranteed to run at least one time, even if the conditions are not met.

Simon Jensen
Simon Jensen
484 Points

I see and understand what the do while loop does. I just do not understand why you would do that in this treestory.

I mean, why would you control if dork or jerk is mention before the user types something.

(I have also made this as a discussion)