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Java Java Basics Perfecting the Prototype Looping until the value passes

Thomas Rossini
Thomas Rossini
544 Points
Posted by Thomas Rossini
Thomas Rossini
544 Points

error 123 cannot find symbol ?

don't know what im doing wrong here

Example.java 
// I have initialized a java.io.Console for you. It is in a variable named console.
String response;
boolean isInvalidWord;
do { response = console.readLine("do you understand do while loops:  ");
    isInvalidWord = (response.equalsIgnoreCase("No"));
   } while (No);

1 Answer

John Lack-Wilson
John Lack-Wilson
8,181 Points
John Lack-Wilson
John Lack-Wilson
8,181 Points

It is because a while loop must evaluate a statement as true or false. Currently you have No as the statement to evaluate, however you do not have a variable named No.

So for example, if you had while(true) ... then this will cause an infinite loop which will continue running forever (well, until you hit command C, or run out of memory and your computer crashes).

One of the ways to fix this may be to do the following:

String response;

do { 
    response = console.readLine("do you understand do while loops:  ");
} while (response.equalsIgnoreCase("No"));

Note I haven't checked if the above code works, just a quick potential fix.