title: How do you parse input from a text file in JAVA?
body: <p>I tried to parse the String from my input.txt file, but I get the NumberFormatException thrown every time. I've added all the code that I have so far.
  I have tried .trim as well. I am very new to text files in Java; therefore, I have no idea what is wrong here. However, any bit of help would be appreciated. </p>
  
  <pre><code>import java.io.File;
  import java.io.FileNotFoundException;
  import java.io.PrintWriter;
  import java.util.InputMismatchException;
  import java.util.NoSuchElementException;
  import java.util.Scanner;
  
  public class Lab5_Exceptions_Redo extends Exception {
  
      public static void main(String[] args) throws FileNotFoundException {
  
          String file = "inputt.txt";
          String file1 = "outputt.txt";
          String file2 = "errorr.txt";
  
          PrintWriter errorr = new PrintWriter(file2);
  
          PrintWriter inputt = new PrintWriter(file);
          inputt.println(15951);
          // int whatever = Integer.parseInt(file);
          // System.out.print(whatever);
          inputt.close();
          Scanner scan = new Scanner(file);
          String number = scan.nextLine();
          int num = Integer.parseInt(number.trim());
          System.out.printf("%d", num);
  
          PrintWriter outputt = new PrintWriter(file1);
          outputt.println(num);
          outputt.close();
          // inputt.close();
  
          scan.close();
          // System.out.printf("%d", num);
  
          try {
  
          } catch (InputMismatchException e) {
              errorr.println("There was an input mismatch error.");
          } catch (NoSuchElementException e) {
              errorr.println("There is no such element.");
          } catch (UnsupportedOperationException e) {
              errorr.println("An unsupported operation occured.");
          } catch (NumberFormatException e) {
              System.out.println(e.getMessage());
              e.printStackTrace();
          }
          errorr.close();
  
      }
  }
  </code></pre>