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Java Java Basics Perfecting the Prototype Looping until the value passes

Diyan Aleksiev
Diyan Aleksiev
4,142 Points
Posted by Diyan Aleksiev
Diyan Aleksiev
4,142 Points

do while loop

String response; String AnswerNo; do {response = console.readLine("Do you understand do while loops? "); }while(AnswerNo.equals("No"));

Example.java 
String response;
String AnswerNo;
do {response = console.readLine("Do you understand do while loops? ");
   }while (AnswerNo.equals("No"));

1 Answer

Katie Wood
Katie Wood
19,141 Points
Katie Wood
Katie Wood
19,141 Points

Hi there,

You're really close - this code is throwing a syntax error due to AnswerNo not being initialized (it isn't given a value when declared or in the loop and then it tries to compare it to something at the end, which is throwing an error).

It's worth noting that you don't actually need the AnswerNo variable, though - response is the one you're changing, so that should be the one you compare to at the end of the loop. The code should look something like:

String response;
do {response = console.readLine("Do you understand do while loops? ");
   }while (response.equals("No"));

If you use AnswerNo as the comparison at the end of the loop, it will never pass, because AnswerNo is never changed - it will loop forever. Comparing to response allows the user to answer something other than "No", which will allow the loop to stop.