Java gui and java threads

Question

public class Temp_sim implements Runnable {

private double temperature = 21.0;
private double set_temp = 21.0;
private long sleeptime = 100;
@Override
public void run() {

    while(true){

        if(temperature <= set_temp)
        {
            temperature = temperature +0.1;

        }
        else if(temperature > set_temp)
        {   
            new Runnable(){

                @Override
                public void run() {

                    for(double i = 0.0; i < 2.0;i = i+0.05)
                    {
                        temperature = temperature -0.05;
                    //  System.out.println("Temperature is: \t"+temperature);
                        try {
                            Thread.sleep(sleeptime);
                        } catch (InterruptedException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                    }

                } 

            }.run();
        }
    //  System.out.println("Temperature is: \t"+temperature);

        try {
            Thread.sleep(sleeptime);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }



}

public double getTemperature() {
    return temperature;
}

public void setTemperature(double current_temp) {
    this.set_temp = current_temp +1;
}
public double getSetTemp(){
    return set_temp;
}
}

in this class, I have a thread simulating a temperature as a double, I then use start and use the thread in another class:

@SuppressWarnings("serial")
public class Temperature_GUI extends JFrame {

private JPanel contentPane;
private JTextField textField;
private TimeSeries series;
private Timer timer = new Timer(250, new tempListener());
Temp_sim temp = new Temp_sim();
Thread thread = new Thread(temp);
private JTextField textField_1;

public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {
        public void run() {
            try {
                Temperature_GUI frame = new Temperature_GUI();
                frame.setVisible(true);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    });
}

/**
 * Create the frame.
 */
@SuppressWarnings("deprecation")
public Temperature_GUI() {

    thread.start();

    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setBounds(100, 100, 1150, 600);
    contentPane = new JPanel();
    contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
    contentPane.setLayout(new BorderLayout(0, 0));
    setContentPane(contentPane);

    JPanel Button_Panel = new JPanel();
    contentPane.add(Button_Panel, BorderLayout.EAST);
    Button_Panel.setLayout(new BorderLayout(0, 0));

    JPanel panel = new JPanel();
    Button_Panel.add(panel, BorderLayout.NORTH);
    panel.setLayout(new BoxLayout(panel, BoxLayout.PAGE_AXIS));

    JPanel panel_1 = new JPanel();
    panel.add(panel_1);

    JButton btnUp = new JButton("Up");
    panel_1.add(btnUp);
    btnUp.addActionListener(new BtnUpActionListener());
    btnUp.setPreferredSize(new Dimension(150, 105));

    textField = new JTextField();
    Font font = new Font("Tahoma",Font.PLAIN,30);
    textField.setText(String.valueOf(temp.getSetTemp())+" \u2103");
    textField.setEditable(false);
    textField.setPreferredSize(new Dimension(95,95));
    textField.setFont(font);
    textField.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
    panel.add(textField);
    textField.setColumns(10);

    JPanel panel_2 = new JPanel();
    panel.add(panel_2);

    JButton btnDown = new JButton("Down");
    panel_2.add(btnDown);
    btnDown.addActionListener(new BtnDownActionListener());
    btnDown.setPreferredSize(new Dimension(150, 105));

    JLabel lblCurrentTemperature = new JLabel("current temperature:");
    panel.add(lblCurrentTemperature);

    this.textField_1 = new JTextField();
    panel.add(this.textField_1);
    this.textField_1.setColumns(10);
    final Timer updater = new Timer(1000, new ActionListener() {
        public void actionPerformed(ActionEvent e) {
             DecimalFormat df = new DecimalFormat("##.00");
            String getTemp = df.format(temp.getTemperature());
             textField_1.setText(getTemp+" \u2103");
        }
    });
    this.textField_1.setEditable(false);

    JPanel panel_3 = new JPanel();
    Button_Panel.add(panel_3, BorderLayout.SOUTH);

    JButton btnReturn = new JButton("Return");
    btnReturn.addActionListener(new BtnReturnActionListener());
    btnReturn.setPreferredSize(new Dimension(150, 105));
    panel_3.add(btnReturn);
    updater.start();
    JPanel center = new JPanel();
    contentPane.add(center, BorderLayout.CENTER);


    this.series = new TimeSeries("Temperature", Millisecond.class);
    final TimeSeriesCollection dataset = new TimeSeriesCollection(this.series);
    final JFreeChart chart = createChart(dataset);
    timer.setInitialDelay(1000);
    chart.setBackgroundPaint(Color.LIGHT_GRAY);

    final ChartPanel chartPanel = new ChartPanel(chart);
    chartPanel.setPreferredSize(new java.awt.Dimension(800, 500));
    center.add(chartPanel);
        timer.start();
}

private JFreeChart createChart(final XYDataset dataset) {
    final JFreeChart result = ChartFactory.createTimeSeriesChart(
        "Temperature Component",
        "Time",
        "Temperature"+" ("+"\u2103"+")",
        dataset,
        true,
        true,
        false
    );

    final XYPlot plot = result.getXYPlot();

    plot.setBackgroundPaint(new Color(0xffffe0));
    plot.setDomainGridlinesVisible(true);
    plot.setDomainGridlinePaint(Color.lightGray);
    plot.setRangeGridlinesVisible(true);
    plot.setRangeGridlinePaint(Color.lightGray);


    ValueAxis xaxis = plot.getDomainAxis();
    xaxis.setAutoRange(true);

    //Domain axis would show data of 60 seconds for a time
    xaxis.setFixedAutoRange(60000.0);  // 60 seconds
    xaxis.setVerticalTickLabels(true);

    ValueAxis yaxis = plot.getRangeAxis();
    yaxis.setRange(0.0, 50.0);

    return result;
}
private class tempListener implements ActionListener{
    double lastValue;
     public void actionPerformed(ActionEvent e) {

           this.lastValue = temp.getTemperature();
            final Millisecond now = new Millisecond();
         //   this.series.add(new Millisecond(), this.lastValue);

            series.addOrUpdate(now, lastValue);

        }
}
private class BtnUpActionListener implements ActionListener {
    public void actionPerformed(ActionEvent e) {
        double current_temp = Double.valueOf(textField.getText().substring(0, 3)) +1.0;
        temp.setTemperature(current_temp);
        textField.setText(String.valueOf(current_temp)+" \u2103");

    }
}
private class BtnDownActionListener implements ActionListener {
    public void actionPerformed(ActionEvent e) {

        double current_temp = Double.valueOf(textField.getText().substring(0, 3)) -1.0;
        temp.setTemperature(current_temp);
        textField.setText(String.valueOf(current_temp)+" \u2103");


    }
}
private class BtnReturnActionListener implements ActionListener {
    public void actionPerformed(ActionEvent e) {

        setVisible(false);
    }
}
}

Now, the million dollar question! I have another class (a navigator between GUI for other simulations, if you will)

And i need to read the same data as this started thread, but how do i do that without instantiating a new thread? This has been troubling me for days.