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Java Java Basics Perfecting the Prototype Looping until the value passes

Posted by sandeep pyla
sandeep pyla
Courses Plus Student 2,915 Points

do while loop

got stuck for two days please help any one

Example.java 
// I have initialized a java.io.Console for you. It is in a variable named console. 
String response = console.readLine("Do you understand do while loops?" );
//String noun;
boolean isInvalidWord;

    do{
   // noun = console.readLine("Enter a noun:  ");
      isInvalidWord=(response.equalsIgnoreCase("No"));
    if(isInvalidWord){
      console.printf("Do you understand do while loops?\n");
      }
    }while(isInvalidWord);
Matt Nickele
Matt Nickele
468 Points
Matt Nickele
Matt Nickele
468 Points

at what point does it not work?

sandeep pyla
sandeep pyla
Courses Plus Student 2,915 Points

it worked finally but it shows error of communication problem dont know wats the problem .

2 Answers

jcorum
jcorum
71,830 Points

Sandeep, you can just test in the condition of the do-while loop:

String response;

do {
  response = console.readLine("Do you understand do while loops?");
} while (response == "No");
console.printf("Because you said %s, you passed the test!", response);

Here you create the variable, outside the do while loop so it stays in scope for the printf statement after the loop. Then you ask the user the question, and store the answer in the response variable. Then you check to see if the response is No or not, in the condition (response == "No").

Qui Le
Qui Le
10,998 Points
Qui Le
Qui Le
10,998 Points

Hi Sandeep, I have seen your code, and I am not sure if you got the solution. I'll like to explain how to make your code executable.

// I will use your variable, noun

String noun;

do {

  // Read in user's reply

  noun = console.readLine("Do you understand do-while loops? Enter Yes or No: ");

} while (noun == "No"); // Loop will repeat until noun is different from "No"

console.printf("You replied with %s. So, you have understood do-while loops", noun);