Swing graphics programming

Question

Hello everyone!! can you help;I am new to java programming. I have this project assignment to develop a small sofware that reads a file and use the data in the file to plot the graph, the prgm can read the file when the file name is entered but getting it to plot the graph, i am struggling with. please see the code below
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.*;
import javax.swing.*;
import java.awt.geom.*;
import java.awt.Graphics.*;
import java.awt.Graphics2D.*;
public class BioxSim extends JFrame {
     static Float a1=200F,a2=500F;//x
static Float b1=200F,b2=75F;//y
//JTextField to hold input data .
private JTextField data_in;
private JTextField data2_in;
//JLabel to show output results.
private JLabel degreesC;
private JLabel fileLabel;
//JTextArea to hold output results.
private JTextArea ta;
private FileReader readfile ;
private BufferedReader buffer ;
private JButton loadButton;
private JButton plotButton;
private JButton maths1;
private JButton maths2;
private JButton tempConversion;
private JButton saveButton;
private JButton clearButton;
private String line;
//Constructor for GoodDocs class - this method is used to set up the GUI
public BioxSim() {
// call the JFrame parent class with the window title
super("Data Conversion");
// we need the container for JFrames in order to add components
Container container = getContentPane();
FlowLayout flow = new FlowLayout();
     container.setLayout(flow);
     JLabel title = new JLabel("**************************************************************** Data Conversion Program *****************************************************");
     container.add(title, new BorderLayout().NORTH);
//pos.gridx = 00; pos.gridy = 00;
// container.add(title);
// private label for the input units
JLabel units = new JLabel("X, Y Data ");
// private label to store prompt text
JLabel prompt = new JLabel(" Input data for [X], [Y] coorinates ");
     JLabel fileLabel = new JLabel("File been Accessed is :" +line );
     // create an instance of the JLabel holding the output result
degreesC = new JLabel("****************************** Example data: Input Degrees F; Output DegreesC Temp ******************************");
// pos.gridx = 0; pos.gridy = 3;
//container.add(prompt, pos);
// create an instance of the JTextField for a specific number of columns
data_in = new JTextField(15);
     data2_in = new JTextField("C: ", 18 );
     ta = new JTextArea(" The Output Data is Used to Plot the graph Below.", 3,62);
     loadButton = new JButton("Load File");     
plotButton =new JButton("PlotGraph");
maths1 = new JButton("Maths1");
maths2 = new JButton("Maths2");
     tempConversion = new JButton("tempConversion");
saveButton = new JButton("Save");
     clearButton = new JButton("Clear");
//pos.gridx =0; pos.gridy = 6;
          container.add(degreesC);
container.add(prompt);
container.add(data_in);
          container.add(units);
          container.add(loadButton);
container.add(data2_in);
          container.add(plotButton);
          container.add( maths1);
          container.add(maths2);
          container.add(tempConversion);
          container.add(saveButton);
container.add(clearButton);
          container.add(fileLabel);
container.add(ta);
          JScrollPane scroll = new JScrollPane(ta,
               JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
               JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
          container.add(scroll);
          CustomPanel panel = new CustomPanel();
          //Dimension dim = new Dimension(500, 400);
          //JPanel panel = new JPanel();
          panel.setPreferredSize( new Dimension(700,300));
panel.setMinimumSize( new Dimension( 200, 100 ) );
          JScrollPane scroll1 = new JScrollPane(panel);
          container.add(scroll1);
// register the TextField event handler - this is an inner class
TextFieldHandler handler = new TextFieldHandler();
data_in.addActionListener(handler);
loadButton.addActionListener(handler);
// set the applications size and make it visible
setSize(800, 550);
setVisible(true);
class CustomPanel extends JPanel
public void paintComponent (Graphics painter)
painter.setColor(Color.white);
painter.fillRect(0,0,getSize().width,getSize().height);
Color customPurple = new Color(128,0,128);
painter.setColor(customPurple);
painter.drawString("graph",250,60);
//Horizontal coordinate of the graph.
     Graphics2D X_line2D = (Graphics2D) painter;
Line2D.Float X_line = new Line2D.Float(40F, 200F, 650F, 200F);
X_line2D.draw(X_line);
X_line2D.drawString("X coordinate", 50, 325);
//Vertical coordinate of the graph.
Graphics2D Y_line2D = (Graphics2D) painter;
Line2D.Float Y_line = new Line2D.Float(200F, 450F, 200F, 20F);
Y_line2D.draw(Y_line);
//Line representing mathematical functions, where a[n],b[n] resp.are variables.
     Graphics2D Y1_line2D = (Graphics2D) painter;
     //graphdata(a2,b2);
Line2D.Float Y1_line = new Line2D.Float(a1, b1, a2, b2);
Y1_line2D.draw(Y1_line);
//This method is used to execute the application */
public static void main(String args[]) {
// create an instance of our application
BioxSim application = new BioxSim();
// set the JFrame properties to respond to the window closing event
application.setDefaultCloseOperation(
JFrame.EXIT_ON_CLOSE );
private String convertFtoC(String input) {
//variables to store the real values of the Strings
double tempF = 0.0;
double tempC = 0.0;
// use a try-catch block to contain data conversion exceptions
try {
// use the Double wrapper class to parse the string to a double
tempF = Double.parseDouble(input);
catch (NumberFormatException nfe) {
// no need to do anything here - errors will leave tempF = 0.0
// perform the conversion
tempC = 5.0 / 9.0 * (tempF - 32.0);
// return the result as a String
return Double.toString(tempC);
private String convertFtoC1(String input) {
// variables to store the real values of the Strings
double tempF = 0.0;
double tempC = 0.0;
// FileReadTest f = new FileReadTest();
// f.readMyFile("input");
// use a try-catch block to contain data conversion exceptions
try {
// use the Double wrapper class to parse the string to a double
tempF = Double.parseDouble(input);
catch (NumberFormatException nfe) {
// no need to do anything here - errors will leave tempF = 0.0
// perform the conversion
tempC = tempF;//5.0 / 9.0 * (tempF - 32.0);
// return the result as a String
return Double.toString(tempC);
/** Class TextFieldHandler implements ActionListner to provide the event handling
for this application. It is a private inner class, which gives it access to
all of the GoodDocs instance variables */
private class TextFieldHandler implements ActionListener {
/** This method is required for an ActionListener to process the events */
public void actionPerformed(ActionEvent event) {
String string = "";
          String filename = null;
String taString;
// The user pressed Enter in the JTextField textField1
if(event.getSource() == data_in){
// retrieve the input as a String
          // degreesC.setText("Input temperature is:" string "DegreeF");
string = convertFtoC(event.getActionCommand());
          ta.setText(string);
// The user pressed Enter in the JTextField textField1
if(event.getSource() == loadButton)
          filename = string;
               // retrieve the input as a String
     filename = data2_in.getText();
               //fileLabel.setText("File been read is : " +filename );
     try
                    readfile = new FileReader(new File(filename));
                    buffer = new BufferedReader (readfile);
                    String lineRead = buffer.readLine();
               //clears the imput area     
               ta.setText("");
                    do
                    ta.append(lineRead+ "\n");
while ((lineRead = buffer.readLine()) != null);
               buffer.close();
               catch (IOException e)
                    if(event.getSource() == clearButton){ 
                    ta.setText("");
} // end of the private inner class TextFieldHandler
} // end of public class GoodDocs
DATA FILE e.g.
Time[sec]     VD[g/m3]     VDFlux[g/m3h]     Flux[g/m2h]     AmbT[C]     AmbRH[%]     ProbeT[C]     ProbeRH[%]     CondenserT[C]     HeatsinkT[C]
0     1.025237E-02     0     -108.264     16.7752     61.27579     23.63191     48.14857     23.30489     23.22949
0.421     1.025237E-02     0     -108.264     16.7752     61.27579     23.63191     48.14857     23.30489     23.22949
0.828     1.025237E-02     0     -108.264     16.7752     61.27579     23.63191     48.14857     23.30489     23.22949
1.218     1.025581E-02     3.179105E-02     -108.229     16.7752     61.2831     23.63191     48.15666     23.30489     23.22949
1.609     1.025891E-02     2.856279E-02     -108.1975     16.7752     61.28748     23.63191     48.16799     23.30489     23.22949
1.968     1.025972E-02     8.050361E-03     -108.1893     16.7752     61.29041     23.63191     48.17554     23.30489     23.22949
2.343     1.026729E-02

Answer 1

Don't forget to use the "Code Formatting Tags",
see http://forum.java.sun.com/help.jspa?sec=formatting,
so the posted code retains its original formatting.