Thread: Not printing in console. What am i missing?

Morning. Working on a project. It builds and compiles but it doesnt display data in the console ? I have an input file that i am using but cant understand why I dont see anything in the console.
Below is the code. I have no errors when compiling.

What am i missing?



This is the input text for the input.txt file

This is a test, this is only a test!
This test is a test of your Java programming skills!
xyz
ABCDEFGHIJKLMONPQRSTUVWXYZ1234567890-=_+ !
end data

public class Project1 
{
    /**
     * @param args the command line arguments
     * @throws java.io.FileNotFoundException
     */
    public static void main(String[] args) 
                            throws FileNotFoundException, IOException
    {   
      FileReader inputStream = new FileReader("input.txt");       
 
        class StringConversion
        {
        public String lowerCaseString = "";
 
            public String lowerCaseString(String trimmed)
                {
                lowerCaseString = trimmed.toLowerCase();
                return this.lowerCaseString;
                }
        }
    }
 
       public static class ThreeMethods
    {
     //white space
 
            public static String trimmed(String s)
            {
                if (s == null)
                {
                    return "";
                }
                return s.trim();
            }
        //return a trimmed string of size len
        public static String trimmed(String s, int len)
        {
            String retVal = ThreeMethods.trimmed(s);
            if (len > retVal.length())
            {
                len = retVal.length();
            }
            return retVal.substring(0,len);
        }
        //convert all double spaces to a single space
        public static String squeeze(String s)
        {
            return s.replace("  ", " ");
        }
    }
 
        //This method will read strings from the input file 
    //and perform manipulations on each string. The results of the 
    //manipulations are displayed in the text area
 
       private void displayStrings() 
                            throws Exception
    {         
        FileReader inputStream = new FileReader("input.txt");
        BufferedReader reader= new BufferedReader(inputStream);
 
        //        
        //Get the next line in the file                        
        //
            String str = reader.readLine();
 
 
                        //Trim and Squeeze
                System.out.print("Trim & Squeeze: " + ThreeMethods.squeeze(ThreeMethods.trimmed(str)) + "\n");
                //Trim, Squeeze, and Shorten to 10 characters
                System.out.print("Trim, Squeeze, Shorten to 10: " + ThreeMethods.trimmed(ThreeMethods.squeeze(ThreeMethods.trimmed(str)),10) + "\n");
                //Trim, Squeeze, lower-case and shorten to 20 characters
                System.out.print("Trim, Squeeze, Shorten to 20, lower-case: " + ThreeMethods.trimmed(ThreeMethods.trimmed(ThreeMethods.squeeze(ThreeMethods.trimmed(str)),20)) + "\n");
                System.out.print("\n");
 
 
            }
    }
}

What code should print on the console?
How is that code being executed?
If the print statements are not executed, nothing is printed.
Starting from the main method, how do the print statements get executed?

Are there any compiler errors? Copy the full text and paste it here.

Ok that answers my first question. Now what about the next questions I asked:
2)How is that code being executed?
If the print statements are not executed, nothing is printed.
3)Starting from the main method, how do the print statements get executed?

The three methods should print out?

A method is not executed unless it is called.
Where does the code call any of the methods?

Do you know what I mean when I say "call a method"?
lowerCaseString = trimmed.toLowerCase(); // this statement calls the toLowerCase method

I think you are missing how the java program executes your code. It starts by calling the main() method. Then each statement in the main method is executed in turn. When the end of the main method is reached, execution for your program stops. (This is modified when other threads are involved)
If the main method does not call any other methods, those other methods are not executed.

For a method to be executed, it must be called. Where does the main method call any methods?

Take a look at the tutorial: https://docs.oracle.com/javase/tutor...arguments.html