Exercise 6.11: stripComments

I am trying to resolve a problem on the website called Practice-It:

Write a method called stripComments that accepts a Scanner representing an input file containing a Java program as its parameter, reads that file, and then prints the file's text with all comments removed. A comment is any text on a line from // to the end of the line, and any text between /* and */ characters. For example, consider the following text:

import java.util.*;

/* My program
by Suzy Student */
public class Program {
    public static void main(String[] args) {
        System.out.println("Hello, world!"); // a println
    }

    public static /* Hello there */ void foo() {
        System.out.println("Goodbye!"); // comment here
    } /* */
}
If the file contained this text, your program should output the following text:

import java.util.*;


public class Program {
    public static void main(String[] args) {
        System.out.println("Hello, world!");
    }

    public static  void foo() {
        System.out.println("Goodbye!");
    }
}

I am not a student but am trying to learn coding on my own.
I would appreciate some guidance.


public static void stripComments(Scanner input){

    String line = "";
    while(input.hasNextLine()){
        line = input.nextLine();
        if(line.contains("/*") && !line.contains("*/" )){
            
            System.out.println();
           
        }else if( line.contains("*/")){
            
        }else if(line.contains("//") ){
            int index = line.indexOf("//");
            System.out.println(line.substring(index-index, index));
        }
        else{
            System.out.println(line);
        }
        
        
    }
    
}

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DOCDGAAsked:
Who is Participating?
 
awking00Connect With a Mentor Commented:
The file I attached writes the text without comments to the console and also creates a NewProgram.java file without the comments from the text you supplied as an example, although I modified it somewhat to accommodate text like -
/* comment starts here
comment goes on here or
* goes on here and
*/ comment ends here
Let me know if ou need any further explanation.
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phoffricConnect With a Mentor Commented:
how about 0 instead of index-index.
Your line approach is acceptable, although a char-by-char approach may be easier to write.
Using line by line, when you encounter a /*, then you can immediately print up to the index, and set a foundComment flag. If */ not on that line, then you are done.

When reading in new lines, if the foundComment flag is true, keep searching for the */ on that line and don't print the line if not found.

I think given the code you showed, you may be able to take it from there for other cases.
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DOCDGAAuthor Commented:
Thanks awking00 and phoffric

awking00, I don't see the attachment
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There are many ways to learn to code these days. From coding bootcamps like Flatiron School to online courses to totally free beginner resources. The best way to learn to code depends on many factors, but the most important one is you. See what course is best for you.

 
awking00Commented:
I only supplied that because the asker stated he was not a student in his initial question but was trying to learn using a practice website.
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DOCDGAAuthor Commented:
Thanks awking00 for your help and did not mean to violate any terms. I was able to solve my problem.
	public static void stripComments(Scanner input){
		//FLAG TO CHECK IF MARKER WAS FOUND
		// /* OR */
		boolean markerFound = false;
		
		while(input.hasNextLine()){
			//PLACE LINE IN VARIABLE
			String line = input.nextLine();
			
			if(markerFound == false && !line.contains("//") && !line.contains("/*") && !line.contains("*/")){
									System.out.println(line);					
			}else {
				if(line.startsWith("/*")){ 
				System.out.print("");
				markerFound = true;
				}else if(!line.contains("/*") && line.endsWith("*/")){
					System.out.println();
					markerFound = false;
				}else if (line.contains("//")){
					int index = line.indexOf('/');
					System.out.println(line.substring(0,index));
				}else {
					int index = line.indexOf("/*");
					int index2 = line.indexOf("*/");
					System.out.println(line.substring(0, index) + "" + line.substring(index2 + 2,line.length())	);
				}
			}
		
		}
	}

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DOCDGAAuthor Commented:
Thanks Netminder

I would like to know what would be appropriate way of asking my questions. I am not trying to violate any terms but I am self teaching myself java. I ordered the Building Java Programs book from Amazon and do not have the aid of a teacher but need to respect EE policies. The book uses the practice it website to aid in learning.

Should I state in my questions do not supply solution but point out my mistakes or something to that nature?
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DOCDGAAuthor Commented:
Okay, I understand now. I will post where the material comes from and mention that I want guidance not a solution.
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