Update. csv file when edited in Java

Question

I have a . csv file that contains information, but when I delete information (in this case contacts) from the console output the file . csv is not being updated. How to resolve?

    private void insertContact(String contactName) {
        contactsListModel.addElement(new Contact(contactName));
    }

    private void setContactsList() {
        contactsListModel = new DefaultListModel<Contact>();
        contactsList = new JList<Contact>(contactsListModel);
contactsList.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION);
        contactsList.setLayoutOrientation(JList.VERTICAL);
        contactsList.setVisibleRowCount(-1);
        contactsList.setBackground(Color.LIGHT_GRAY);
        loadContacts();

        add(contactsList, BorderLayout.CENTER);     
    }


    private void setContactsLabel() {
        contactsLabel = new JLabel("Contacts:");
        contactsLabel.setOpaque(true);
        contactsLabel.setBackground(Color.WHITE);

        add(contactsLabel, BorderLayout.NORTH);
    }


        public void loadContacts(){

        BufferedReader br = null;
        String line = "";
        String separator = ";";

        try {

            br = new BufferedReader(new FileReader("diretorio"));
            while ((line = br.readLine()) != null) {
                String[] contactName = line.split(separator);

                contactsListModel.addElement(new Contact(contactName[0]));

                System.out.println( );

            }

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (br != null) {
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
      }
}

Answer 1

You created a method that reads the file and turns it into a contact list. When you remove something from that list, you are only removing it from the list. This is simply expected. Now you need to do a method analogous to that which loads the contacts from the list to save the contacts from the list in a file and call it when you change the list. The easiest way is to make one that recreates the file (erasing what already exists) and printing there in the file one by one of the contacts. It is important to keep the same format you use for reading.