No! No! Got it all wrong.

Question

I am so embarassed as I could have adressed this better. My intention was not trying to get answers to a homework assignment - i am not even in school. I just started trying to learn java on my own. A friend of mine who is a programming professor gave me a few problems to work on. I only wanted advice on how to approach the question not looking for answers, and I apologise if i did not make myself clear enough. I should have asked for help with my coding instead.
Sorry!

Answer 1

Here's a few lines to start you off (needs error handling, data validation and a whole bunch of other stuff, to complete your assignment)
import java.io.*;import java.util.*;import javax.swing.*;import javax.swing.event.*;
import java.awt.*;import java.awt.event.*;class PhoneAccount{
public static void main(String args[]){new PhoneGUI();}}
class PhoneGUI extends JFrame implements ActionListener{
ArrayList callsMade = new ArrayList();DefaultListModel listModel;JList jList;
JButton addBtn = new JButton("Add Record");JButton deleteBtn = new JButton("Del Record");
JTextField phoneNumberTf = new JTextField(20);JTextField typeTf = new JTextField(3);
JTextField costTf = new JTextField(8);  JLabel phoneNumberLbl = new JLabel("Phone Number:           ");
JLabel whereLbl = new JLabel("                    Type:      ");
JLabel costLbl = new JLabel(" Cost:");public PhoneGUI(){super("Phone Account");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);Container frame = getContentPane();
frame.setLayout(new BorderLayout());listModel = new DefaultListModel();
jList = new JList(listModel);jList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
JScrollPane listScrollPane = new JScrollPane(jList);addBtn.addActionListener(this);
deleteBtn.addActionListener(this);JPanel upper = new JPanel(new BorderLayout());
JPanel labels = new JPanel(new FlowLayout());JPanel texts = new JPanel(new FlowLayout());
JPanel btns = new JPanel(new FlowLayout());labels.add(phoneNumberLbl,FlowLayout.LEFT);
labels.add(whereLbl);labels.add(costLbl,FlowLayout.RIGHT);
upper.add(labels,BorderLayout.NORTH);texts.add(phoneNumberTf);texts.add(typeTf);
texts.add(costTf); upper.add(texts,BorderLayout.CENTER);btns.add(deleteBtn);
btns.add(addBtn);upper.add(btns,BorderLayout.SOUTH);JPanel lower = new JPanel();
lower.add(listScrollPane);frame.add(upper, BorderLayout.NORTH);
frame.add(lower, BorderLayout.SOUTH);pack();
Dimension dim = Toolkit.getDefaultToolkit().getScreenSize();
setLocation((dim.width - frame.getWidth())/2, (dim.height - frame.getHeight())/2);
setResizable(false);setVisible(true);try{loadPhoneLog();}catch(IOException e){}}
public void actionPerformed(ActionEvent ae){try{if(ae.getSource() == addBtn){
PhoneCall pc = new PhoneCall();pc.callNumber = phoneNumberTf.getText();
pc.callType = typeTf.getText().charAt(0);pc.callCost = Double.parseDouble(costTf.getText());
pc.printToFile();loadPhoneLog();phoneNumberTf.setText("");typeTf.setText("");
costTf.setText("");}else{if(jList.getSelectedIndex() >= 0){
callsMade.remove(jList.getSelectedIndex());savePhoneLog();loadPhoneLog();}
else JOptionPane.showMessageDialog(null,"Delete failure - no record selected");}}
catch(IOException e){}}private void loadPhoneLog() throws IOException{try{
BufferedReader br = new BufferedReader(new FileReader("PhoneLog.txt"));String line;
callsMade.clear();listModel.clear();while((line = br.readLine()) != null) callsMade.add(line);
br.close();sortCallsMade();for(int i = 0; i < callsMade.size(); i++){
listModel.addElement(callsMade.get(i));}jList.ensureIndexIsVisible(callsMade.size()-1);}
catch(FileNotFoundException fnfe){}}private void sortCallsMade(){String temp[] = new String[callsMade.size()];
for(int i = 0; i < temp.length; i++){temp[i] = (String)callsMade.get(i);}
Arrays.sort(temp);callsMade.clear();for(int i = 0; i < temp.length; i++){callsMade.add(temp);}}
private void savePhoneLog() throws IOException{FileWriter fw = new FileWriter("PhoneLog.txt");
for(int i = 0; i < callsMade.size(); i++) fw.write(callsMade.get(i).toString()+"\n");fw.close();}}
class PhoneCall{String callNumber;char callType;double callCost;
public void printToFile() throws IOException{FileWriter fw = new FileWriter("PhoneLog.txt",true);
fw.write(callNumber + " " + callType + " " + callCost + "\n");fw.close();}}