Plz need help with this hashmap program

Question

as far as i know, this hashmap program works, but i cant get it to compile correctly because of one line error:
phoneArray[2] = int f;
the second position in phoneArray is and will always be a number, but the array is a String array, making it difficult for me to take the number in that position and change it.
In actuality, the number is a score (a grade) and i need to take it to change it to a letter grade, where it will later be spit out in order from Name, Year, Score, Grade.
plz help, this is a school assignment and its driving me mad.
import java.util.*;
import java.io.*;
* A class that represents a phone book.  This phone
* book maps names to phone numbers.  This will
* read teh phone book information from a file.
public class CourseData2 {
  /////////////////// fields ///////////////////
  private String fileName;
  private Map phoneMap = new HashMap();
  /////////////////// constructors ///////////////////
   * Constructor that takes a file name and reads
   * in the names and phone numbers from a file.
   * @param file the name of the file to read
  public CourseData2(String file) {
    this.fileName = file;
    // Read the map information in form the file
    readInfoFromFile();
  } // constructor
  /////////////////// methods ///////////////////
   * Get the phone number for hte passed nam
   * @param name the name to look up in hte map
   * @return the phone number if found, else null
  public String getPhoneNumber(String name) {
    String phoneNumber = (String) phoneMap.get(name);
    return phoneNumber;
  } // method getPhoneNumber()
   * Method to read the phone information from a
   * file and use it to fill hte map
  public void readInfoFromFile() {
    String line = null;
    String[] phoneArray = null;
    try {
      // create the reader
      BufferedReader reader =
        new BufferedReader(new FileReader(fileName));
      // loop reading from the file
      while ((line = reader.readLine()) != null) {
        if (line.indexOf(":") >= 0) {
          phoneArray = line.split(":");
          phoneMap.put(phoneArray[0].trim(),
                       phoneArray[1].trim(),
                       phoneArray[2].trim());
        } // if
        } // while
        (int)phoneArray[2] = int f;
        if (f < 60) { (String)a = "E";}
        else if (60 <= f < 70) { (String)f = "D";}
        else if (70 <= f < 80) { (String)f = "C";}
        else if (70 <= f < 90) { (String)f = "B";}
        else if (90 <= f) { (String)a = "A";}
      // Close the reader
      reader.close();
    } // try
    catch (FileNotFoundException ex) {
      SimpleOutput.showError("Could not find the file \"" + fileName + "\".");
    } // catch
    catch (Exception ex) {
      ex.printStackTrace();
    } // catch
  } // method readInfoFromFile()
  public void printBook() {
    // Sort hashtable.
    Vector phoneVector = new Vector(phoneMap.keySet());
    Collections.sort(phoneVector);
    // Display (sorted) hashtable.
    for (Enumeration phoneEnumeration = phoneVector.elements(); phoneEnumeration.hasMoreElements();) {
      String key = (String)phoneEnumeration.nextElement();
      System.out.println("Name: " + key + ", Year: " + phoneMap.get(key) + ", Score: " + phoneMap.get(key) + ", Grade: " + phoneMap.get(key));
    } // for
  } // method printBook()
  /* main method for testing */
  public static void main(String[] args) {
    CourseData2 phoneBook = new CourseData2("scores12.txt");
    System.out.println(phoneBook.getPhoneNumber("Lee"));
    System.out.println(phoneBook.getPhoneNumber("Smith"));
    phoneBook.printBook();
  } // main()
} // class

Answer 1

after much time and editing, this is the revised coding:
import java.util.*;
import java.io.*;
* A class that represents a class score book.  This
* book maps names to scores and grades.  This will
* read the names, scores and grade information from a file.
public class CourseData2 {
  /////////////////// fields ///////////////////
  private String fileName;
  private Map phoneMap = new HashMap();
  /////////////////// constructors ///////////////////
   * Constructor that takes a file name and reads
   * in the names and phone numbers from a file.
   * @param file the name of the file to read
  public CourseData2(String file) {
    this.fileName = file;
    // Read the map information in form the file
    readInfoFromFile();
  } // constructor
  /////////////////// methods ///////////////////
   * Get the phone number for hte passed nam
   * @param name the name to look up in hte map
   * @return the phone number if found, else null
  public String getPhoneNumber(String name) {
    String phoneNumber = (String) phoneMap.get(name);
    return phoneNumber;
  } // method getPhoneNumber()
   * Method to read the phone information from a
   * file and use it to fill hte map
  public void readInfoFromFile() {
    String line = null;
    String[] phoneArray = null;
    String a = "";
    try {
      // create the reader
      BufferedReader reader =
        new BufferedReader(new FileReader(fileName));
      // loop reading from the file
      while ((line = reader.readLine()) != null) {
        while ((line = reader.readLine()) != null) {
        if (line.indexOf(":") >= 0) {
          phoneArray = line.split(":");
          int f = Integer.parseInt(phoneArray[2]);
          if (0 <= f && f <= 100) {
        if (0 <= f && f < 60) { a = "E";}
        else if (60 <= f && f < 70) { a = "D";}
        else if (70 <= f && f < 80) { a = "C";}
        else if (80 <= f && f < 90) { a = "B";}
        else if (90 <= f && f <= 100) { a = "A";}
          } // if f between 0 and 100
        else if ( f > 100 && f < 0 )  {
        SimpleOutput.showError("Score is not an integer");
        String g = new String();
        g = phoneArray[2];
          }//if < 0
        }// if (line.index....
        phoneMap.put(phoneArray[0].trim(),
                    (phoneArray[1].trim() + phoneArray[2].trim() + (String)a));
        } // while2
        } // while
      // Close the reader
      reader.close();
    } // try
    catch (FileNotFoundException ex) { 
      SimpleOutput.showError("Could not find the file \"" + fileName + "\".");
    } // catch
    catch (Exception ex) {
      ex.printStackTrace();
    } // catch
  } // method readInfoFromFile()
  public void printBook() {
    // Sort hashtable.
    Vector phoneVector = new Vector(phoneMap.keySet());
    Collections.sort(phoneVector);
    // Display (sorted) hashtable.
    for (Enumeration phoneEnumeration = phoneVector.elements(); phoneEnumeration.hasMoreElements();) {
      String key = (String)phoneEnumeration.nextElement();
      System.out.println("Name: " + key + ", Year: " + phoneMap.get(key) + ", Score: " + phoneMap.get(key) + ", Grade: " + phoneMap.get(key));
    } // for
  } // method printBook()
  /* main method for testing */
  public static void main(String[] args) {
    CourseData2 phoneBook = new CourseData2("scores12.txt");
    System.out.println(phoneBook.getPhoneNumber("Depp"));
      System.out.println(phoneBook.getPhoneNumber("Gonzales"));
        System.out.println(phoneBook.getPhoneNumber("Jenkins"));
            System.out.println(phoneBook.getPhoneNumber("Lee"));
               System.out.println(phoneBook.getPhoneNumber("Mac Donald"));
                  System.out.println(phoneBook.getPhoneNumber("O'Malley"));
                     System.out.println(phoneBook.getPhoneNumber("Price"));
                        System.out.println(phoneBook.getPhoneNumber("Ramesh"));
                            System.out.println(phoneBook.getPhoneNumber("Smith"));
                                System.out.println(phoneBook.getPhoneNumber("Winston"));
    phoneBook.printBook();
  } // main()
} // classthis has no errors, but gives me 4 warnings, which i can't solve, plz help