Thread: Print Writer Problem

I need help on figuring out how to send data to a file without it replacing the data and also repeating other data. The code below doesnt replace any darta, but it repeats data that i want in there (which i dont want replacing):

 public void writeCustomerData()
 
    {
        try{
        Frame owner = null; //Sets the owner of the file to null.
        FileDialog newFileDialog1 = new FileDialog(owner, "Open", FileDialog.SAVE); //Creates a fileDialog object.
        newFileDialog1.setVisible(true); //Chooses the file that will be read in.
        File newFile1 = new File(newFileDialog1.getFile());
 
        if(customerMap.size()> 0)
        {
 
          for(Customer customers : customerMap.values())
            {
             PrintWriter nw = new PrintWriter(new FileWriter(newFile1,true)); 
             nw.print("ok");
              customers.writeData(nw);
              nw.close();
            }
        }
        else
        {
            System.out.println("No Customers In The List");
        }
    }
    catch(FileNotFoundException a)
    {
        System.out.print("File cannot be found");
    }
    catch(IOException a)
    {
        System.out.print("File cannot be found");
    }
}

well the data i want is in a map , but i need to have that in a loop to get them all , but have other data not repeat where it says ok i need that only once!

i need one piece of data to write once , followed by all data in a hashmap with out no replacing of the data beause all the data append each other

it has to be a hash map cz i will have to be able to get them later via the key. is there a way of doing it the way i want . n its not the map thats repeating its the other information.