ObjectOut/InputStream problem

Question

I have a problem on writing objects to a binary file. Let say, everytime the writeOBJ button is triggered in main program, "public void writePet(PetRecord newPet)" is invoked and the passing object is written to the ObjectOutputstream.
The problem is, it is writing the same object over and over again eventhough the passing objects are different.
(I make sure the passing objects are dfferent.)
Also, appending is not working too....eventhough i said
ObjectOutputStream outputStream = new ObjectOutputStream(new FileOutputStream("filename.records",true));
the followindg is part of my code.....
import java.io.*;
import java.util.*;
import javax.swing.*;
public class MyFile
     private static int index = 0;
     private ObjectInputStream inputStream = null;
     private ObjectOutputStream outputStream = null;
     private Vector<PetRecord> readPetV = new Vector<PetRecord>(30);
     //private Vector<PetRecord> writePetV  = new Vector<PetRecord>(30);
     private boolean flagOutput = false;
     private boolean flagInput = false;
     public boolean getOutputflag()
          return flagOutput;
     public boolean getInputFlag()
          return flagInput;
     public int getIndex()
          return index;
     @SuppressWarnings("unchecked")
     public Vector<PetRecord> getReadPetV()
          return(Vector<PetRecord>)readPetV.clone();
//==============================================================================================
     //Method for creating new file.
          public void connectToOutputFile()
               boolean newFile = false;
               do{
                    try
                         String fileName = JOptionPane.showInputDialog(null,
                                   "Please Enter the New file name","FileName.records");
                         File fileObject = new File(fileName);
                         if(!fileObject.exists())
                              outputStream = new ObjectOutputStream(new FileOutputStream(fileName.trim()));
                              newFile = true;
                              flagOutput = true;
                         else
                              JOptionPane.showMessageDialog(null,"File "+ fileName +" is already exist.");
                              newFile = false;
                              flagOutput = false;
                    catch (IOException exp)
                         JOptionPane.showMessageDialog(null,"Error Opening output file.");
                         newFile = false;
                         flagOutput = false;
               }while(!newFile);
//==============================================================================================
     //opening the input file for the display
          public void connectToInputFile()
               boolean inputError = true;
               String inputFileName = null;
               do
                    inputFileName = JOptionPane.showInputDialog(null,
                              "Please Enter the File name to Read from","FileName.records");
                    inputFileName = inputFileName.trim();
                    try
                         inputStream = new ObjectInputStream(new FileInputStream(inputFileName));
                         outputStream = new ObjectOutputStream(new FileOutputStream(inputFileName, true));
                         inputError  = false;
                         flagInput = true;
                         flagOutput = true;
                    catch(FileNotFoundException exp)
                         JOptionPane.showMessageDialog(null,"File "+inputFileName+" not found.");
                         inputError = true;
                         flagInput = false;
                    catch(IOException e)
                         JOptionPane.showMessageDialog(null,"Error Opening Input file"
                                   +inputFileName);
                         inputError = true;
                         flagInput = false;
               }while(inputError);
//==============================================================================================
     public void writePet(PetRecord newPet)
               try
                    outputStream.writeObject((PetRecord)newPet);
                    outputStream.flush();
               catch(IOException e)
                    JOptionPane.showMessageDialog(null,"Error writing to file.");
                    System.exit(0);
          public void writePet(PetRecord newPet)
               writePetV.addElement(newPet);
          public void writePetV()
               for(int i=0; i < writePetV.size(); i++)
                    try {
                         outputStream.writeObject((PetRecord)writePetV.elementAt(i));
                    } catch (IOException e) {
                         // TODO Auto-generated catch block
                         e.printStackTrace();
//==============================================================================================
//read method for reading the object from the file
          public void readData()
               //reading the objects datas from file
               PetRecord readNext;
               try
                    while((readNext = (PetRecord)inputStream.readObject()) != null)
                         readPetV.addElement((PetRecord)readNext);
                         System.out.println(readNext.getName());
               catch (Exception e)
                    //JOptionPane.showMessageDialog(null,"End of record");
               index = readPetV.size();
//==============================================================================================
//     method for closing files.
          public void closeFile()
               if (flagOutput)
                    try
                         outputStream.close();
                    catch(IOException e)
                         JOptionPane.showMessageDialog(null, "Error Closeing file"
                                   + e.getMessage());
                         System.exit(0);
                    catch(NullPointerException empty)
                         JOptionPane.showMessageDialog(null,"There is nothing to close. DUHH!!!!");
               if (flagInput)
                    try
                         inputStream.close();
                    catch(IOException e)
                         JOptionPane.showMessageDialog(null, "Error Closeing file"
                                   + e.getMessage());
                         System.exit(0);
                    catch(NullPointerException empty)
                         JOptionPane.showMessageDialog(null,"There is nothing to close. DUHH!!!!");
[/code]

Answer 1

Ok! I think i solved the problem. In the main program I used one major object to pass through to the write() method. let's say constructed an PetRecord object and everytime I wanna add user input, I used "mutators" (set methods) of that Object and pass to the write(PetRecord newPet) method. It seems that eventhough the new values were taken by the newPet Object, it stills wirte the old one to the object stream. I don't know why that happen.
So, what i did is, every time i want to add user input, I create a new Object of PetRecord class and it works fine.
Does anybody have any idea why that happen???
but appeending to a file still doesn't work though!!! I'm trying to fix it....