Thread: I can't key in the data

here is my main program

import java.io.IOException;
import java.util.NoSuchElementException;
import java.util.Scanner;
 
public class TransactionProcessor
{
   private FileEditor dataFile;
   private RandomAccessMarkingRecord record;
   private MenuOption choices[] = { MenuOption.SEARCH,
     MenuOption.INSERT_MARKS,MenuOption.DELETE, MenuOption.END };
 
   private Scanner input = new Scanner (System.in);
 
   //get the file name and open the file
   private boolean openFile()
   {
      try //attempt to open file
      {
        //call the helper method to open the file
        dataFile = new FileEditor( "students.dat");
      }//end try
      catch(IOException ioException)
      {
        System.err.println( "Error opening file." );
        return false;
      } //end catch
 
      return true;
    } //end method openFile
 
    //close file and terminate application
    private void closeFile()
    {
       try // close file
       {
          dataFile.closeFile();
       }//end try
       catch ( IOException ioException )
       {
          System.err.println("Error closing file.");
          System.exit(1);
       }//end catch
     }//end method closeFile
 
     //create, update or delete the record
     private void performAction(MenuOption action )
     {
 
       int idNumber; // id number for record 
       String firstName; // first name for record
       String lastName; // last name for record
       int examMark; // exam mark for record
       int assessment; // assessment mark for record
 
       try //attempt to manipulate files based on option selected
       {
         switch ( action ) //switch based on option selected
         {
           case SEARCH:
                System.out.println();
                dataFile.readRecords();
                break;
       case INSERT_MARKS:
                System.out.printf( "\n %s %s",
               "ENTER ID NUMBER, FIRST NAME, LAST NAME, EXAM MARK and ASSESSMENT MARK,\n",
                   " ******(ID NUMBER MUST BE IN 4 DIGITS (BETWEEN 2000 AND 2099)****** \n");
 
        idNumber = input.nextInt(); //read id number
         firstName = input.next(); //read first name
        lastName = input.next(); //read last name
        examMark = input.nextInt(); //read exam mark
          assessment = input.nextInt();//read assessment mark
           dataFile.newRecord(idNumber, firstName, lastName, examMark, assessment );// create new record
 
        break;
 
            case DELETE:
                System.out.print(
            "\n Enter an id number to delete : " );
             idNumber = input.nextInt();
 
                  dataFile.deleteRecord ( idNumber );//delete record
             break;
            default:
           System.out.println("Invalid action." );
              break;
        }//end switch
       }//end try
       catch ( NumberFormatException format )
       {
          System.err.println( "Bad input." );
       }//end catch
       catch (IllegalArgumentException badIdNumber )
       {
              System.err.println(badIdNumber.getMessage() );
       }//end catch
       catch (IOException ioException)
       {
           System.err.println("Error writing to the file.");
       }//end catch      
       catch (NoSuchElementException elementException )
       {
           System.err.println( "Invalid input. Please try again.");
           input.nextLine(); //discard input so uder can try again
       }//end catch
    }//end method performAction
 
    //enable user to input menu choice
    private MenuOption enterChoice()
    {
       int menuChoice = 1;
 
       //display available options
       System.out.printf("\n %s \n %s \n %s \n %s \n %s ",
     "Enter your choice", "1 - List marks",
     "2- Add marking records","3- Delete a marking record", 
        "4- End \n?");
 
       try
       {
    menuChoice = input.nextInt();
       }
       catch ( NoSuchElementException elementException )
       {
         System.err.println( "Invalid input.");
      System.exit(1);
       }//end catch
 
       return choices[ menuChoice - 1 ]; //return choice from user
    }//end enterChoice
 
    public void processRequests()
    {
       openFile();
 
    //get user's request
    MenuOption choice = enterChoice();
 
    while( choice != MenuOption.END )
     {
       performAction( choice );
       choice = enterChoice();
        }//end while
 
        closeFile();
    }//end method processRequests
}//end class TransactionProcessor

The problem is, when I key in the data, the screen displayed "error writing to the file"... how can it be??