While loop and cannot find symbol errors

[Collie Mason]

Hi! I'm writing some code for class that will take two strings and remove any instances of the 2nd string (plus the digit before) from the first. Most of is working fine as far as I can tell, but I'm currently running into 2 reoccurring errors:

StringRemover.java:22: error: incompatible types: String cannot be converted to boolean
    while(cleaned.substring(remove)) 
                         ^
StringRemover.java:32: error: cannot find symbol
		return sentence + " - String to remove " + remove + cleaned;
		                                                    ^
  symbol:   variable cleaned
  location: class StringRemover
2 errors

The first error indicates that the way I'm attempting to create a loop which will continue as long as instances of "remove" exist is incorrect, but I'm not sure how else to phrase this? I do not understand what the issue is with my second error. Can anyone help me resolve these errors?

Full code is included below:

import static java.lang.System.*;
import java.util.Scanner;

public class Main
{
	public static void main( String args[] )
	{
		//add test cases
		
		Scanner keyboard = new Scanner(System.in);
		
		out.print("Enter original phrase ::");
		String s = keyboard.next();
		out.print("Enter phrase to be removed ::");
		String rem = keyboard.next();
		StringRemover test = new StringRemover();
		out.println(test);

	}
}

class StringRemover
{
   private String sentence;
   private String remove;
   private int slength;
   private int rlength;

	public void setRemover(String s, String rem)
	{
    sentence = s;
    remove = rem;
	}

	public String removeStrings()
	{
		String cleaned = sentence;
		slength = sentence.length();
		rlength = remove.length();
    while(cleaned.substring(remove)) //Source of first error. I'm trying to have the loop continue while there are iterations of "remove" to be removed. How should I phrase this?
    {
      cleaned = sentence.substring(0, (sentence.indexOf(remove) - 1)) + sentence.substring((sentence.indexOf(remove) + rlength), slength);
    }
		return cleaned;
	}

	public String toString()
	{
	  removeStrings();
		return sentence + " - String to remove " + remove + cleaned;
	}
}

Thank you!

[Liutauras Vilda]

If I understood correctly what are you trying to achieve here, I think you over-engineered it.

But...

Could you please give an example of input(s) and tell what the expected output(s) supposed to be, so that way will be easier to understand (at least for me), what is your goal.

[Liutauras Vilda]

As for one of those erros if to follow error message blindly:

StringRemover.java:22: error: incompatible types: String cannot be converted to boolean
   while(cleaned.substring(remove))

it tells you that while () condition is expecting boolean value and not the String.
Expected:

while (evaluatesToTrue) {
   do something
}

You have (doesn't make sense):

while ("word") {
    do something
}

[Liutauras Vilda]

Check String class's replaceAll() method whether it wouldn't be of use in your program.

[Collie Mason]

Thank you so much!

Could you please give an example of input(s) and tell what the expected output(s) supposed to be, so that way will be easier to understand (at least for me), what is your goal.

Simple Data:
xR-MxR-MHelloxR-M and R-M
(which should output "Hello")
fuxqwexqwertyxqwexqwertyrtyxqwertyrtyn and qwerty
(which would output "fun")

while (evaluatesToTrue) {
   do something
}

Addressing the above, how can I change my current code to fit that format?

Check String class's replaceAll() method whether it wouldn't be of use in your program.

The replaceAll() suggestion seems like it would work (and I appreciate the suggestion), but at a glance I feel like it would eliminate the need for the loop (which is what I'm trying to get practice with in this code). Am I misinterpreting this?

[Liutauras Vilda]

Collie Mason wrote:Simple Data:
xR-MxR-MHelloxR-M and R-M
(which should output "Hello")

So how those "x"s get removed?

[Liutauras Vilda]

Collie Mason wrote:The replaceAll() suggestion seems like it would work... but at a glance I feel like it would eliminate the need for the loop

Correct, and that is why standard Java set of libraries exist, to help developers to re-use solutions to the common problems and concentrate on the business logic, instead of trying to reinvent wheel.

[Collie Mason]

Oh sorry, I must've forgotten to clarify! The code should remove the letter before the instance of "remove" to be deleted as well as the instance itself. That should remove the "x"s in the example.

[Liutauras Vilda]

Collie Mason wrote:Oh sorry, I must've forgotten to clarify! The code should remove the letter before the instance of "remove" to be deleted as well as the instance itself. That should remove the "x"s in the example.

Ok, in which case replaceAll() won't help you much. Second input and output example also clarifies that.

[Liutauras Vilda]

Collie Mason wrote:remove any instances of the 2nd string (plus the digit before)

Collie Mason wrote:Simple Data:
xR-MxR-MHelloxR-M and R-M
(which should output "Hello")
fuxqwexqwertyxqwexqwertyrtyxqwertyrtyn and qwerty
(which would output "fun")

And where those digits are as I don't seem to see them?

Asking all these questions so all would have a better understanding with what kind of complex task we are dealing with.

[Collie Mason]

It's fine, I appreciate the help.
If I'm understanding your question correctly, the String of which all instances should be removed is the second ("R-M" in the first example), whereas the String which the instances are to be removed from is the first ("xR-MxR-MHelloxR-M"). The "digits" as I referred to them in-

remove any instances of the 2nd string (plus the digit before)

are the "x"s you previously asked about. Which I clarified here-

Oh sorry, I must've forgotten to clarify! The code should remove the letter before the instance of "remove" to be deleted as well as the instance itself. That should remove the "x"s in the example.