The file just won't load into array...Please Help!

Question

hi i need some help in loading a binary file into an array so that i can edit the data that was saved from previous run..
i could save the file but after that when i try to load it back to memory...i can't...ie. all the information keyed in were lost...please help
this is the Code for the loading process...
     public static void loadAircraft (ArrayList aircraft) {
          try {
               FileInputStream filein = new FileInputStream(".\\Data\\Aircraft.bin");
               ObjectInputStream objectin = new ObjectInputStream(filein);
               Aircraft craft = (Aircraft) objectin.readObject();
               aircraft.add(craft);
               objectin.close();
               filein.close();
          catch (Exception e) {}
     }the above code won't load anything into memory...is there a way for overcoming this?
inside the Aircraft class there are four different data of which they contain two differen data types.
one of which is String and the other three are in int.
Awaiting for reply...thanks

Answer 1

yes...its some objects of an array that i am trying to load back...
erm...i'll show you the whole code maybe...
//to reference the swing library
import javax.swing.*;
import java.util.*;
import java.io.*;
public class SetupAircraft {
     static ArrayList aircraft;
     public static void init () {
          aircraft = new ArrayList(5);
          loadAircraft(aircraft);
     //opens up another sub group while the user
     //entered 1 as his/her option in the SetupSystem
     //menu
     public static void Setup () {
          //this will create a string that is going to be displayed
          //in the input dialog box
          String menu = "  Please select an option:  \n"
                          +"----------------------------\n"
                          +"1) Add New Aircraft\n"
                          +"2) Edit Existing Aircraft\n"
                          +"3) List Aircraft\n"
                          +"4) Delete Existing Aircraft\n"
                          +"5) Save\n"
                          +"6) Return to Main Menu\n\n"
                          +"   Enter a number between 1-6\n";
          //declare a field named option for selection through menu
          int option = 0;
          //continue the loop until the user inputs the number 6
          do {
               //error handling for the input from the menu
               //if the input is not integer the error is caught and
               //reassigning option to be 0
               try {
                    option = Integer.parseInt(JOptionPane.showInputDialog(null, menu,
                               "Setup Aircraft", JOptionPane.QUESTION_MESSAGE));
               catch (NumberFormatException e) {
                    option = 0;
               //determine which option the user has chosen
               //and enters the respective section
               switch (option) {
                    case 1: add(aircraft);
                              break;
                    case 2: edit(aircraft);
                              break;
                    case 3: list(aircraft);
                              break;
                    case 4: //delete(aircraft);
                              break;
                    case 5: save(aircraft);
                              break;
                    case 6:     return;
                    default: JOptionPane.showMessageDialog(null, "Please enter a number between 1-6",
                               "Alert", JOptionPane.ERROR_MESSAGE);
                               option = 0;
          while (true);
     public static void add (ArrayList aircraft) {
          String type = "";
          int first = 0;
          int business = 0;
          int economy = 0;
          do {
               try {
                    type = JOptionPane.showInputDialog(null,"Enter Aircraft Type", "Prompt for Type",
                    JOptionPane.QUESTION_MESSAGE);
                    try {
                         if(aircraft.contains(type)) {
                              JOptionPane.showMessageDialog(null, type + " already exist!",
                              "Error", JOptionPane.ERROR_MESSAGE);
                              type = "-100";
                    catch (Exception e) {}
                    if (type=="-100");
                    else if (type.length()==0) {
                         JOptionPane.showMessageDialog(null, "Please enter an aircraft type",
                         "Error", JOptionPane.ERROR_MESSAGE);
                    else if (!(type.startsWith("-",3))) {
                         JOptionPane.showMessageDialog(null, "Please enter the aircraft type with XXX-XXX format where X is integer.",
                         "Error", JOptionPane.ERROR_MESSAGE);
                         type = "0";
               //catch the input error that the user has produces.
               catch (Exception e) {
                    return;
          while (!(type.startsWith("-",3)));
          //try to ask the user for the passenger's name and if the name field contains
          //no characters at all repeat the prompt for name field until the user presses
          //Cancel.
          try {
               first = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter First Class Capacity",
               "Prompt for Capacity", JOptionPane.QUESTION_MESSAGE));
          catch (Exception e) {
               String error = "For input string:";
               if (e.getMessage() == "null") {
                    return;
               else if (e.getMessage().startsWith(error)) {
                    JOptionPane.showMessageDialog(null, "Please enter only numbers",
                    "Error", JOptionPane.ERROR_MESSAGE);
          try {
               business = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter Business Class Capacity",
               "Prompt for Capacity", JOptionPane.QUESTION_MESSAGE));
          catch (Exception e) {
               String error = "For input string:";
               if (e.getMessage() == "null") {
                    return;
               else if (e.getMessage().startsWith(error)) {
                    JOptionPane.showMessageDialog(null, "Please enter only numbers",
                    "Error", JOptionPane.ERROR_MESSAGE);
          try {
               economy = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter Economy Class Capacity",
               "Prompt for Capacity", JOptionPane.QUESTION_MESSAGE));
          catch (Exception e) {
               String error = "For input string:";
               if (e.getMessage() == "null") {
                    return;
               else if (e.getMessage().startsWith(error)) {
                    JOptionPane.showMessageDialog(null, "Please enter only numbers",
                    "Error", JOptionPane.ERROR_MESSAGE);
          Aircraft newAircraft = new Aircraft (type, first, business, economy);
          aircraft.add(newAircraft);
          JOptionPane.showMessageDialog(null, "Aircraft Sucessfully Added",
          "Successful", JOptionPane.INFORMATION_MESSAGE);
     public static void edit (ArrayList aircraft) {
          String type = "";
          int first = 0;
          int business = 0;
          int economy = 0;
          do {
               try {
                    type = JOptionPane.showInputDialog(null, "Enter Aircraft Type to Edit",
                    "Prompt for Type", JOptionPane.QUESTION_MESSAGE);
                    if (type.length()==0) {
                         JOptionPane.showMessageDialog(null,"Please enter an aircraft type",
                         "Error",JOptionPane.ERROR_MESSAGE);
                    else if (!(type.startsWith("-",3))) {
                         JOptionPane.showMessageDialog(null, "Please enter the aircraft type with XXX-XXX format where X is integer.",
                         "Error", JOptionPane.ERROR_MESSAGE);
                         type = "0";
               catch (Exception e) {
                    return;
          while (!(type.startsWith("-",3)));
          try {
               int edited = aircraft.indexOf(new UniqueAircraft(type));
               Aircraft craft = (Aircraft)aircraft.get(edited);
               try {
                    first = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter First Class Capacity",
                    "Prompt for Capacity", JOptionPane.QUESTION_MESSAGE));
               catch (Exception e) {
                    String error = "For input string:";
                    if (e.getMessage() == "null") {
                         return;
                    else if (e.getMessage().startsWith(error)) {
                         JOptionPane.showMessageDialog(null, "Please enter only numbers",
                         "Error", JOptionPane.ERROR_MESSAGE);
               try {
                    business = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter Business Class Capacity",
                    "Prompt for Capacity", JOptionPane.QUESTION_MESSAGE));
               catch (Exception e) {
                    String error = "For input string:";
                    if (e.getMessage() == "null") {
                         return;
                    else if (e.getMessage().startsWith(error)) {
                         JOptionPane.showMessageDialog(null, "Please enter only numbers",
                         "Error", JOptionPane.ERROR_MESSAGE);
               try {
                    economy = Integer.parseInt(JOptionPane.showInputDialog(null, "Enter Economy Class Capacity",
                    "Prompt for Capacity", JOptionPane.QUESTION_MESSAGE));
               catch (Exception e) {
                    String error = "For input string:";
                    if (e.getMessage() == "null") {
                         return;
                    else if (e.getMessage().startsWith(error)) {
                         JOptionPane.showMessageDialog(null, "Please enter only numbers",
                         "Error", JOptionPane.ERROR_MESSAGE);
               Aircraft newAircraft = new Aircraft (type, first, business, economy);
               aircraft.add(newAircraft);
               aircraft.add(newAircraft);
               JOptionPane.showMessageDialog(null, "Successfully edited aircraft\n"+type+" to capacities\n"
               +"First: "+first+"\n"+"Business: "+business+"\n"+"Economy: "+economy,
               "Successful", JOptionPane.INFORMATION_MESSAGE);
          catch (Exception e) {
               JOptionPane.showMessageDialog(null,e.getMessage(),"Error",JOptionPane.ERROR_MESSAGE);
     public static void list (ArrayList aircraft) {
          JOptionPane.showMessageDialog(null, aircraft.size()+" aircraft found", "Found",JOptionPane.INFORMATION_MESSAGE);
          Object[] aircrafts;
          aircrafts = aircraft.toArray();
          for (int i=0;i<aircraft.size();i++) {
               Aircraft a = (Aircraft) aircrafts;
               JOptionPane.showMessageDialog(null, a, "Aircrafts" + (i+1), JOptionPane.INFORMATION_MESSAGE);
     public static void save (ArrayList aircraft) {
          try {
               FileOutputStream fileout = new FileOutputStream(".\\Data\\Aircraft.bin");
               ObjectOutputStream objectout = new ObjectOutputStream(fileout);
               Object[] aircrafts;
               aircrafts = aircraft.toArray();
               objectout.writeObject(aircrafts);
               objectout.close();
               fileout.close();
               JOptionPane.showMessageDialog(null,aircraft.size()+" aircrafts saved", "Sucessful", JOptionPane.INFORMATION_MESSAGE);
          catch (IOException e) {
               JOptionPane.showMessageDialog(null,e.getMessage(),"Error",JOptionPane.ERROR_MESSAGE);
     public static void loadAircraft (ArrayList aircraft) {
          try {
               FileInputStream filein = new FileInputStream(".\\Data\\Aircraft.bin");
               ObjectInputStream objectin = new ObjectInputStream(filein);
               Aircraft craft = null;
               while ((craft=(Aircraft)objectin.readObject())!=null) {
                    aircraft.add(craft);
               objectin.close();
               filein.close();
          catch (Exception e) {
               JOptionPane.showMessageDialog(null,e.toString());
               e.printStackTrace();
i think thats a bit too long..but it would explain what i am trying to save...its linking to the class Aircraft tho...
thanks...i appreciate your help...