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Java Java Basics Perfecting the Prototype Looping until the value passes

Posted by Zachary Menendez
Zachary Menendez
454 Points

Don't understand why I can't get this do while loop to work I did the same thing as the guy in the video and no luck.

i'm trying to make this work but i'm hsving no luck at all I don't understand what i'm doing wrong I need to make it keep running if someone says no.

Example.java 
// I have initialized a java.io.Console for you. It is in a variable named console.
  String response;                
do {
  response = console.readLine("Do you understand do while loops");
  boolean isAnswerValid = (response.equalsIgnoreCase("yes"));
  if (isAnswerValid) {
    console.printf("you do understand do while loops");
    } while(isAnswerValid);
}
Gábor Molnár
Gábor Molnár
9,928 Points
Gábor Molnár
Gábor Molnár
9,928 Points

The problem is that you need to add while to the do statement and not to the if . So a do-while loop looks like this correctly:

do {
  // some kind of code here
} while ( /* here some condition */ )

Here is the solution for your problem:

  // Initialize response as string
  String response;
do {
  // Wait for a console input from the user
  response = console.readLine("Do you understand do while loops");
 // If the answer is yes (in any kind of case), isAnswerValid will be true, otherwise it will be false
  boolean isAnswerValid = (response.equalsIgnoreCase("yes"));
  if (isAnswerValid) { 
    console.printf("you do understand do while loops"); // this will be printed if the isAnswerValid is true
  }
} while(isAnswerValid) // if this is true, then do block will run again

This loop firstly runs and asks for a question and wait for an input. Then it will be running until the condition in the while won't be false.